Earth Science 1121 misterm1 study guide
Recumbant Syncline
"Shortening" Crustal shortening Folding back over itself like an S Ductile deformation
Big Bang Theory
(cosmology) The theory that the universe originated 20 billion years ago from the cataclysmic explosion of a small mass of matter at extremely high density and temperature. All mass and energy in a single point.
Where do Earthquakes happen?
Along fault lines / plate boundaries Brittle failures, cold dense rock, near the surface None lower than 700km Do not occur in warm, ductile rock
Divergent Margin
Also called a spreading center. Magma rises to form new oceanic crust between the two pieces of the original plate. As it ascends, the rock experiences a decrease in pressure and partially melts. Midocean ridge - Volcanic activity Makes new oceanic crust from middle and spreads outwards Ridge risen a bit above sea floor bc less dense (hot less dense magma cummin up thru) Earthquakes - 0-10km, small only goes thickness of the crust (10km) Normal faults form parallel lines across margin
Burial metamorphism produces ____________. a. foliated rocks only b. nonfoliated rocks only c. both foliated and nonfoliated rocks
B
If the earth had no core and instead was filled with mantle material to its center, then which of the above travel time charts correctly shows the new P-wave arrival times?
B
Shield Volcanoes
Broad, gently sloping cones constructed of lava flows. Basaltic in composition, found over hot spots and divergent boundaries. Generally non-violent.
Primary Waves (P-Waves)
1st wave, P, travels the fastest, back-and-forth waves, move through solids, liquids, and gases. ComPressional.
How many directions of cleavage are indicated in the diagram? 2 pieces of paper intersecting
2
Crust
2/3 is made of oxygen and silicon elements
Syncline
Downward fold like a smily face Ductile Deformation
Lava
Exterior molten rock
Compression Waves
Shorter wave length/high frequency
Most important rock-building material
Silicates
The most common mineral group within Earth are the ____________
Silicates
What is the crust made up of?
Silicon, light, brittle elements
Models
Similar to a theory Constrained by/designed to match data Fill in gaps where data is lacking Help to formulate a hypothesis that can be tested Can represent past, present, or future trials
Denser Materials
Sink down into the earth iron
Ductile flow
Slow, like silly putty. Still faster than nothing Solid rock can flow bc of h2O presence
Crustal root
Swelling of crust under a mountain. More crust on top = much more crust on bottom bc density floating on mantle 1 mountain needs 5 root
Viscocity
Tendency of rock to resist flow More viscous = colder, flows less, more sticky Less viscious = warmer flows faster, less sticky
The boundary between the crust and mantle is marked by a seismic-velocity discontinuity called ____________
The Moho
In silicate minerals, tetrahedra may be coordinated to form long one-dimensional chains, extensive two-dimensional sheets, or massive three-dimensional frameworks (T or F)
True
Subducted slabs have never been detected below the Wadati-Benioff zone. (T or F)
True
The number of lithospheric plates on the Earth has been variable through geologic time. Hundreds of millions of years ago, there were plates that no longer exist today.
True
What happens to wave velocity as depth increases?
Velocity increases
The form of small, poorly developed crystals is termed ______________ .
anhedral
Minerals are classified into groups primarily on a basis of chemistry, specifically the _________ within the chemical formula
anions
Cleavage in minerals refers to a tendency to break ___________
along planes of weakness
Moving into interior of Earth, temperature ____________.
and pressure both increase
The lithosphere lies atop the _____________ .
asthenosphere
Deep oceanic trenches are features of ____________ plate boundaries
convergent
Deep oceanic trenches are features of ____________ plate boundaries.
convergent
Large, thick, non-volcanic mountain belts, like the Himalayas are features associated with ____________ plate boundaries.
convergent
Subduction zones are _________ plate boundaries
convergent
The lithosphere of the Earth is generally thickest at and near ____________ plate boundaries.
convergent
The volcanoes of the Cascades Mountains are related to melting of rock associated with a ____________ plate boundary.
convergent
plate boundary where two plates collide (subduction zone)
convergent
Locations of Volcanic Activity
convergent boundaries, mid oceanic ridges, hot spots
Slab-pull occurs because subducting slabs are ___________ than the surrounding asthenosphere
cooler and more dense
In the picture above, the layer of the Earth labelled with a 1 is called the ________.
crust
Continental lithosphere ____________.
is thicker than oceanic lithosphere
The shininess of a mineral is a helpful diagnostic property termed ____________.
luster
Chemical (Sedimentary)
made from minerals precipitated directly from water
A majority of the melts in the Earth form through the partial melting of ultramafic mantle rock. These newly-formed magmas are ____________.
mafic
Which type of magma has the greatest iron and magnesium content?
mafic
a type of lava that is very hot, with low silica, and low viscosity
mafic
major magma type, consists of lower percentage of silica
mafic
naturally occurring, solid, ordered atomic arrangement, inorganic, formed geologically, definite chemical composition
mineral
Chemical and biochemical rocks are classified primarily on the basis of ___________
mineral composition
The distinction between the crust and mantle is primarily on the basis of a difference in ____________
mineral content
Crystals form when
mineral grains can grow unobstructed
basalt with glassy, ropy texture. forms when lava moves slowly and cools slowly
pahoehoe
The metallic content of Earth's core is ___________
part liquid and solid iron alloy
a type of sedimentary rock that consists of carbon-rich remnants of plants
organic
An episode of mountain building is termed a(n) ____________.
orogeny
exposure due to sea level fall
regression
Regions of the sea floor with negative magnetic anomalies were formed during times when Earth's magnetic field had ____________.
reversed polarity
most abundant component of magma
silica
Shear causes what kind of fault?
strike-slip
earthquakes are common, but volcanoes are absent at _____________ boundaries
transform plate
flooding due to sea level rise
transgression
Sea level rises locally, and marine sediments are deposited on top of terrestrial sediments during events termed ________
transgressions
Speed of light
300,000 km/s
A 1% expansion requires and increase of __________degC and leads to a 1% decrease in density.
300-400C
Mass of Earth
32.1% iron 30.1% oxygen 15.1% silicon 13.9% magnesium 8.8% other
Ocean Crust thickness
8km thick Thin compared to Continental crust bc more dense Easily deformed relatively heavier = floats lower above sea level Oldest is 200mya bc too old, too cold, sinks down
How many silicon ions are involved in the formation of the silicon-oxygen tetrahedron?
?? not 4
The coast of the northwestern United States is an example of a/an_______________ margin. (one word)
?? not convergent
The growth of mineral crystals from a melt is the process of ______________. (one word)
?? not crystallization
A horizontal magma intrusion that displaces the country rock is termed a(n) .
?? not dike
The geothermal gradient is largest in the:
?? not outer core
The distinct, three-dimensioanal arrangement of atoms within a mineral is called the crystal ______________.
?? not structure
Basaltic lavas ____________. a. contain more iron and magnesium than rhyolitic lavas b. contain more silica than rhyolitic lavas c. are more viscous than rhyolitic lavas d. contain a greater proportion of trapped volatiles than rhyolitic lavas
A
In the diagram below, two positive (black) marine magnetic anomalies are labeled A and B. Based on the diagram, which of the following statements is correct?
A is younger than B.
Planet
A large body in space that orbits a star and does not produce light of its own. Has a nearly spherical shape and cleared its neighborhood of orbiting objects (gravity).
Nebula
A large cloud of dust and gas in space. Forms from hydrogen, helium, and other gases after the Big Bang.
Ridge push
A mechanism that may contribute to plate motion; it involves the oceanic lithosphere sliding down the oceanic ridge under the pull of gravity. As the lithosphere moves away from the ridge crest, new hot asthenosphere rises to fill the gap - forming new ocean lithosphere. The upward movement of asthenosphere under the mid-ocean ridge is a consequence of seafloor spreading, not the cause.
Meteorite
A meteoroid that passes through the atmosphere and hits Earth's surface.
Outer core
A layer of molten iron and nickel that surrounds the inner core of Earth.
Mantle plumes
A localized column of hot magma rising by convection in the mantle, believed to cause volcanic activity in hot spots, such as the Hawaiian Islands, away from plate margins.
What is an esker?
A long and narrow ridge composed of well-sorted gravel and sand made from streams flowing through subglacial tunnels
Normal polarity
A magnetic field that is the same as that which exists at present.
San Andreas Fault
A major geological fault in California formed by a sliding transform boundary.
Declination
A measure of how far north or south an object is from the celestial equator.
Edge of visible universe
- lies over 13 billion light years away, which means that light traveling to Earth from this location began its journey about 9 billion years before the Earth even existed.
Where do elements come from?
--Big Bang nucleosynthesis formed the lightest elements. -Atomic #s 1, 2, 3, 4, and 5 (H, He, Li, Be, and B) --Heavier elements are from stellar nucleosynthesis. -Atomic #s 6-26 (C to Fe) -Stars are "element factories." --Elements with atomic #s >26 form during supernovae
Pangea evidence
-Fit of continents. -Climate evidence: Glacial evidence in the southern continents, in particular. -Similar fossils. -Similar rocks. -Similar structural features.
Hawaii 3 hot spots
-Kilauea -Mauna Loa -Mauna Kea
Big Bang Sequence
-hydrogen atoms formed within a few seconds -at three minutes, hydrogen atoms fused to form helium atoms -light nuclei (Be, Li, B) by Big Bang nucleosynthesis
After the Big Bang
-the universe expanded at a constant rate -caused matter to be disturbed non-homogeneously -lumps of denser matter became centers of high gravity and began to accumulate space debris -the clusters became large groups of stars, now called galaxies -atoms began to bond -gravity caused collapse of gaseous nebulae -increases in temperature, density, and rate of rotation
What is the average elevation of the Earth's continental crust?
0-1 km above sea level
Two GPS measuring methods
1) Researchers establish a network of fixed reference points on Earth's surface, often attached to bedrock. The position is re-measured every few months or years. 2) Continuous GPS measurement: the receivers are attached permanently to monuments, and position is estimated at fixed intervals of a few seconds or minutes.
Evidence for Continental Drift
1) continental fit, 2) similarity of fossil plants and animals, 3) similarity of rock sequences, 4) paleomagnetism
Melting point of rocks depends on:
1) pressure - increasing pressure raises melting temperature 2) water content - increased water concentration decreases melting temperature
Spreading rates along mid-ocean ridges vary between __________ cm a year
1-10
Describe the Magnetic Stripes
The Earth has a magnetic field that experience polarity reversals in the geologic past. The only way this polarity reversal and mapping on the oceanic crust can occur is by mid-ocean ridge spreading.
Stars
a fixed luminous point in the night sky that is a large, remote incandescent body like the sun. Immense balls of incandescent gas.
Proplanetary Disk
a large disk-shaped cloud of dust and gas
Moon
a natural object that orbits a planet
A sill is ____________.
a sheetlike intrusion that lies parallel to surrounding layers of sedimentary rock
Formation of moon
a small planentoid collides with earth. the debris forms a ring which compacts into the moon
Iceland rises above the Atlantic Ocean as a result of ____________.
a submarine hot-spot located along a mid-ocean ridge
Cleavage in minerals refers to ____________.
a tendency to break along planes of weakness
Strike-Slip Fault
a type of fault where rocks on either side move past each other sideways with little up or down motion Looking at the other plate, if it moves right, its a right strike slip. If it goes left relative to you, its a let
Reverse Fault
a type of fault where the hanging wall slides upward; caused by compression in the crust pushing together Top block goes up
Distinctive rock sequences on South America terminate at the Atlantic Ocean but reappear on the continent of ____________.
Africa
Rock
Aggregate of minerals
scientist that hypothesized that continents are mobile, had evidence but no means of explaining, ridiculed by science community in 1915
Alfred Wegener
Hypothesis
An educated guess based on observation and can be supported/ rejected through experiment
Where do faults end?
At depth in ductile zone (brittle-ductile boundary) where it gets warm enough to flow
How many seismic stations are needed to locate an earthquake?
At least 3
Element (Big Bang)
Atomic numbers 1-5, Big Bang nucleosynthesis, H + He
An _______ is produced when solar wind particles are directed toward the poles and excite atmospheric gases
Aurora
Seismic P-wave velocities A. generally increase with depth, then abruptly increase at the core-mantle boundary B. generally increase with depth, then abruptly decrease at the core-mantle boundary C. generally decrease with depth, then abruptly increase at the core-mantle boundary D. they do not change with depth
B. generally increase with depth, then abruptly decrease at the core-mantle boundary
Unconformity
Boundary between layers representing a time gap - caused by erosion or lack of sediment deposition
Moho
Boundary between mantle and crust 40km deep
Why do earthquakes occur at plate interiors?
Build up of strain
Isostasy
Buoyancy Less dense crust/rocks rise Denser crust/rocks sink Ex: Ice floats in water bc less dense. The less dense, the more it floats. The more dense, the less it floats.
How are currents created?
By winds from atmosphere- coriolis effect
Which of the above graphics most closely shows the travel-time for P and S waves if the core-mantle boundary was half as deep as it is now, i.e. 1450km deep instead of 2900km deep?
C
f water is the transport medium of sediment, the grain size of sedimentary deposits most closely indicates the ____________. a. geographic extent of the weathering source rock at outcrop b. average velocity of the water from the time of erosion until deposition c. velocity of the water at the moment the sediment settled to the bottom
C
primary difference between phyllite and schist is ____________. a. schist contains mica, but phyllite contains only clay b. phyllite contains mica, but schist contains only clay c. mica crystals within schist are larger than those within phyllite d. mica crystals within phyllite are larger than those within schist
C
Explosive or voluminous eruptions may cause the volcano to collapse on the floor of the (now empty) magma chamber, producing a broad depression termed a ____________.
Caldera
Yellowstone Supervolcano Caldera Eruptions
Caldera eruptions are some of Earth's most explosive volcanic eruptions. No supervolcano caldera eruptions have occurred on Earth in last few thousand years. Ten have occurred in the last 1,000,000 years - three in North America. The most recent eruption of Yellowstone was 630,000 years ago. Eruptions can last for weeks.
Passive Margin
Can become subduction zone Plate boundary without subduction, no collision Area where separation of continental plates began
Comparing ages of rock in diff places
Can find fossils or date rocks and compare age to age of layer in a diff location Example: the youngest rocks in Ohio are really old compared to the newest rocks in California
Cratons
Continental crust thats been there for billions of years ADD MORE
Glatiation
Continental glaciers leave traces, showing in what direction they move.
Continental drift
Continents form together to form the nation of Pangea
What contributes to earth's heat?
Continual impacts Radioactive decay of materials like uranium
Heat transfer that occurs through the movement of a fluid, driven by temperature differences among various points within the fluid, is termed ____________.
Convection
How does the heat move through rocks?
Convection, because rocks are poor conductors of heat.
What are the two ways for heat to leave?
Convection: moving the hot rocks Conduction: moving the heat through the rocks
The Alps, Himalayas, and the Appalachians were all formed by what kind of margin / zone?
Convergent Boundary, reverse fault, but different zone (subduction v collision)
Minerals are resources
Driven humans since Paleolithic age. 10 minerals in iPhones
The deep ocean floor is flat and nearly featureless. (T or F)
False
Virtually all of the sediment atop a downgoing plate becomes subducted into the mantle along with the plate. (T or F)
False
A fracture in the crust, where rocks slide past one another, is termed a ____________
Fault
What Forms Earth's Magnetic Field
Generated electrically by the circulation of Earth's outer fluid core. Circulation driven by Coriolis effect.
Crystals
Macro-scale expression of atomic arrangement, will have consistent crystal geometry
Earth's core
Made of densest material Molten iron and nickel Inner core solid bc of density Outer core liquid
Limestone
Made of shells and coral -Fossiliferous Identifiable shells and fragments -Chert Quartz(silica) shells of plankton
Mantle
Made of very hot, high density silicates (ductile)
Hot, liquid rock beneath the surface of the Earth is termed _________
Magma
Lava
Magma that reaches the surface in a molten state IE) Volcanic eruptions
Which of the following were NOT among the pieces of evidence that Wegener used to hypothesize Continental Drift?
Magnetic anomalies in the sea floor.
What would visitors notice?
Magnetic field, atmosphere, surface features--continents, oceans, polar ice caps
Earth's magnetic field
Magnetic lines of force from Earth's polar north and south, acting like a giant magnet. Generated by convection in Earth's liquid outer core. Deflects solar winds and keeps the atmosphere intact.
Scientific Method
Make Prediction based on hypothesis Collect new data for testing predictions If new data supports hypothesis, confidence in hypothesis increases More predictions confirmed = more confidence in hypothesis
Olympus Mons, the largest known volcano in the Universe, is found on _____
Mars
Supervolcano
Massive volcano that can produce unbelievably enormous, but rare, eruptions.
Atmosphere is made up of mostly
Nitrogen
Presently, Earth's atmosphere is dominated by which two gases?
Nitrogen and Oxygen
Can we say when California will experience the big one?
No, because the Earth is not that predictable.
Is the Earth's interior entirely made up of the rocks that we find at the surface?
No, rocks on interior not same as the entire earth because their densities are different
Tensional stress causes what kind of fault?
Normal
How fast do plates move?
North Atlantic - about 1-2 centimeters/year. South Atlantic - about 1.5-2.5 centimeters/year. East Pacific - about 3-8 centimeters/year.
Which soil horizon has the greatest proportion of organic matter?
O horizon
Iridium
Occurs in Earth's crust in tiny amounts. Common in meteorites. Volcanoes are also a source.
Topographically, most of the ocean floor is made up of __________
Ocean Plains
Earth's interior
Oceanic crust .1%, continental crust .37% (least dense), outer 31% and inner core <2% (most dense), mantle 67% (denser).
In an oceanic and continental crust collision, which one sub-ducts and why?
Oceanic crust, because it is more dense.
Plate boundaries
Oceanic crust- can be destroyed at subduction zone. Continental crust- cannot be destroyed. Too buoyant.
Why are oceans salty and rivers not?
Oceans are final storage of salts Rivers are constantly replenished with fresh water by precipitation
What kind of earthquakes are at subduction zones?
One plate overrides another, they are at deep ocean trenches with mountain ranges
Fossil Record
Only very recent, bc before, there werent organisms with hard bodies that would fossilize Trilobites some of first hard shelled organisms (cambrian)
How does wind perpendicular to shore drive vertical flow?
Onshore - Water piling up along coast drives downwelling. Offshore - Upwelling replaces water moved away. Thermohaline contrast
Hydrocarbons, such as petroleum and natural gas, are classified as _______
Organic Materials
The Crust
Outermost "Skin" of Earth (thickest under mountains, thinnest under mid-ocean ridges)
Most abundant elements (2)
Oxygen and Silicon
The two most common elements in the crust of Earth are ____________.
Oxygen and Silicon
Crustal material
Oxygen, Silicon, aluminum, Iron, Calcium, Sodium, Potassium, Magnesium
Which waves move faster (P or S)?
P waves
evidence for structure inside of crust?
PP, PKP, PcP waves
Fractionation
Partial melting during subduction Material melts at increasing temperatures Low melting temp part melts, separates, rises up bc more bouyant and creates magma chamber of new volcano on continental part of subducton zone (ANDESITE) Higher melting temp part continues down, is made stronger due to lack of melt. (BASALT) Andesites come from melted oceanic basalt
Absolute Age
Radioactive Decay determined Radiometric Dating - radioactive isotope decay to find exact age # of atoms locked in, ratios are constant across all materials 1 half life = half of parent cells gone 2 half lives = half of those gone
What keeps the heat in the core?
Radioactivity
Hot Spots
Random magma rising Andesite or basalt depending on where Causes increased elevation at current location due to buoyancy Plates move around Stationary hot spot As plate gets farther from hot spot, elevation decreases, new volcanoes created in new sites
Specific gravity
Ratio of the density of a mineral to the density of water
Continuous GPS Measurement
Receiver attached permanently to monuments, checked every few seconds/minutes
Asthenosphere
Region of mantle 100km-350km deep Ductile, very hot compared to crust Crust floats on top
What age does stratigraphy give?
Relative Age
Viscosity
Resistance to flow. High viscosity - slower flow. Higher silica content - slower flow. Higher temperature - faster flow. Higher gas conent - faster flow.
Thrust fault
Reverse faults that dip at an angle less than 45 degrees.
Magnitude (size)
Richter movement
Possible Mechanisms of Plate Movement
Ridge Push Gravity Sliding Gravitational Pull - trench suction("suckduction") or slab pull. Mantle Drag - Piggyback on convection cells like rafts in a stream. (Proven wrong)
Less Dense materials
Rise up to the surface Potassium, silicon, aluminum, doium
Transgression & Regression
Rising and falling of sea level Coastal deposit shifts Transgression up Regression down Does stuff with coal Coal in swamps? Coal, sandstone, shale
What factors decreases salinity?
River discharge Precipitation
Rock Deformation
Rock's response to tectonic stress, movement of plates. Result is folding of strata
Away from ridge
Rocks = older, sediment = thicker.
Ridge
Rocks = young, sediment = thin.
Earth is elastic
Rocks bend but dont break
Sedimentary Rock
Rocks formed on the surface Formed by precipitation of material of water at earths surface, or deposition and cementation of debris transported by water, wind, or ice Buncha grains of shit made into a rock
Asteroids
Rocky, metallic objects that orbit the sun but are too small to be considered planets. Most come from asteroid belts between Mars and Jupiter.
How do we know that the outer core is liquid?
S waves are not transmittable, so the outer core must be liquid
What states of matter can S waves move through, and which ones can they not move through?
S waves can move through rocks, but they cannot shear liquid or gasses.
What happens at the core/mantle boundary?
S waves disappear Crystalline structure changes from solid to liquid Rapid decrease in velocity
As depth increases, what happens to salinity, density, and temperature
Salinity and density increase and temperature decreases
Law of Original Horizontality
Sediments originally deposited flat, in layers Oldest layer on bottom Any feature cutting or disrupting a layer is younger
Divergent margin
Spreading center. Magma rises to form new oceanic crust between the two pieces of the original plate. As it ascends, the rock experiences a decrease in pressure and partially melts.
How do you calculate distance from an earthquake by using p and s waves?
Start with degrees on a chart and then find difference between s and p wave
Change in shape, induced by stress, is termed ___________
Strain
What type of earthquakes does a transform fault cause?
Strike-slip earthquakes
Cosmology
Study of the universe. Focus' on structure and history
The largest and the deepest earthquakes occur in ___________ ______.
Subduction Zones
Mountain building
Subduction zone - volcanoes - Andes Collision (after subduction) - Himalayas, Alps
Where are the largest and deepest earthquakes located?
Subduction zones
Convergent plate margin
Subduction, in which two plates are going towards one another and one plate is going under the other, creating volcanoes and extremely powerful earthquakes.
Future of our solar system
Sun-sized stars are not massive enough to end in supernovas
Theory accepted hypothesis
Supported though many experiments - never rejected
What drives thermohaline circulation?
Surface waters sinking in North Atlantic due to increased density
What kind of waves cause destruction?
Surface waves
What drives ocean currents?
Surface winds and surface currents (10%) Temperature and salinity differences (Thermohaline Circulation) (90%)
Eratosthenes (cont.)
Syene, shadow absent (directly overhead) Alexandria, Shadow 7.2°. Estimated that 800km was 1/50th of Earth's circumference
Less common physical properties
Taste, smell, feel, elasticity, magnetism, effervescence (acid test)
Pushing Force
Tendency of midocean ridge creation of new oceanic crust to "push" old crust towards subjection zones as it spreads new crust outwards
What event proved catastrophism wrong?
The "great flood" is scientifically impossible.
Pele's hair consists of thin strands of _______ volcaniclastic debris
basaltic
A fold shaped like an right-side up bowl is a(n) ______
basin
Radioactive isotopes, differentiation of Earth's iron core, gravity driven compression, and meteoric bombardment all caused early Earth to ____________.
be much hotter than at present
With increasing altitude, the concentration of gases in our atmosphere ____________.
becomes less dense
the lithosphere ______ when loaded
bends
Caldera
big, circular depression with steep walls and fairly flat floor, formed as the center of the volcano collapses into the large, drained magma chamber below.
Cemented shells of marine organisms form which kind of sedimentary rock?
biochemical
a type of sedimentary rock that consist of shell organisms
biochemical
Which of the following is NOT a mineral?
both A and B are not minerals; however, C is a mineral
what is moho?
boundary between crust and mantle
A body of rock to which a sudden, rapid stress has been applied is more likely to exhibit ____________ than is a body of rock subjected to a gradually applied stress.
brittle behavior
How do oceans play a critical role in the climate system?
by regulating the temperature and humidity of the lower atmosphere-circulation driven by atmospheric circulation and evaporation/precipitation
Spreading rates along mid-ocean ridges have ____________.
changed through time, and today vary between 1 and 10 cm/yr
Physical precipitation of gypsum due to evaporation of seawater produces which kind of sedimentary rock?
chemical
a type of sedimentary rock that is made from minerals precipitated directly from water
chemical
Hydrolysis, oxidation, and hydration are all examples of _________
chemical weathering
The distinction between the crust and mantle is primarily on the basis of a difference in ____________; the distinction between the lithosphere and asthenosphere is primarily on the basis of a difference in ____________.
chemistry (mineral content); degree of physical rigidity
What formed the Appalachian mountains?
collision of north america and africa
Trace amounts of impurity in a mineral can commonly produce significant differences in ____________ among individual crystals of this mineral.
color
Wegener proposed continental drift after he observed evidence from fossils, glacial deposits, and the fit of the continents that suggested all of the continents were once ____________.
combined to form a supercontinent (he termed Pangaea) in the late Paleozoic through the Mesozoic
Minerals are classified into groups primarily on a basis of ____________.
chemistry, specifically the anions within the chemical formula
A horizontal magma intrusion that displaces the country rock is termed a(n)
chill margin
Of the three primary forms of subaerial volcanoes, ____________ consist of a simple, conical pile of tephra.
cinder cones
Lithified detritus (breakdown products of preexisting rocks) forms which kind of sedimentary rock?
clastic
a type of sedimentary rock that consists of solid fragments and grains cemented together, formed by weathering and erosion
clastic
rocks in which grains are bounded by natural cement, mineral material that precipitates from water and fills the space between grains
clastic
Which type of sediment settles at greater fluid velocities than sand?
clay
The tendency of crystals to break along regular planes of weakness is termed ________________.
cleavage
tendency to break along planes of weakness, produces flat, shiny surfaces
cleavage
you find sediments of different size being deposited at what part of a river
close to the source
the crystalline (grain size) of granite and gabbro
coarse
Gemstones are commonly found in pegmatites, which are igneous rocks that are exceptionally ___________
coarse grained
As compared to aphanitic igneous rocks, phaneritic rocks are __________ grained
coarser
Volcanoes can occur along:
coastal margins, or along divergent margins on interior of continent/plates
When two bodies of continental lithosphere are pulled together at a convergent boundary, the result is __________
collision and mountain formation
When two bodies of continental lithosphere are pulled together at a convergent boundary, the result is ____________.
collision and mountain formation
a sheetlike intrusion that cuts across preexisting layers
dike
a type of tabular intrusion that crosscuts rock fabric
dike
Under the theory of plate tectonics, the plates themselves are pieces of _______ that will move with respect to one another
lithosphere
includes the crust and the upper part of the mantle
lithosphere
part of the crust, relatively rigid, can't flow easily
lithosphere
Rheological layers
lithosphere (brittle); athenosphere (ductile/plastic)
_____ and _____ are distinguished on rigidity, due to temp
lithosphere, asthenosphere
______ plates sink into the ______
lithosphere, asthenosphere
what are the four spheres of the Earth that are responsible for maintaining conditions sustaining life?
lithosphere, atmosphere, biosphere, and hydrosphere
Relaxed waves
longer wavelength, lower frequency
The mid-ocean ridges are elevated above the surrounding seafloor because ridge rocks are hot and therefore of relatively ______ density
low
lava with _____ viscosity will flow farther
low
Basaltic lava
low viscosity (faster flow)
As compared with metamorphism, diagenesis takes place at _________ temps and pressures
lower
higher gas content creates ______ viscosity
lower
higher temp creates _____ viscosity
lower
higher temperature of lava leads to ______ viscosity
lower
The shininess of a mineral is a helpful diagnostic property termed ___________ .
luster
What is the term for liquid rock beneath the surface of the Earth?
magma
It is rare for mineral crystals to display any sort of symmetry (invariance of pattern with respect to a transformation, such as rotation or mirror-image reflection).
false
Sliding motion along transform faults caused the segments of the mid-ocean ridges to become dislocated with respect to one another.
false
That the Earth is a sphereoid is a relatively new discovery, not widely accepted until the 15th Century when it was confirmed by Columbus's voyage.
false
The deep ocean floor is flat and nearly featureless.
false
Wegener's evidence for a united Pangaea was so compelling that virtually all geologists agreed with the idea of continental drift during his lifetime.
false
Pyroclastic Flow
fast-moving avalanche of a mixture of ash and air
What's the term for a fracture in the crust where rocks slide past one another?
fault
Which type of magma has the greatest silica content?
felsic
major magma type, consists of higher percentage of silica
felsic
the crystalline (grain size) of rhyolite, andesite, and basalt
fine
subsurface melt
magma
building blocks of rock
minerals
In a ____________ fault, the fault plane is nonvertical and the hanging-wall block moves downward relative to the footwall block.
normal
Squashing a fly with a fly swatter is an application of ------- stress
normal
Regions of the sea floor with positive magnetic anomalies were formed during times when Earth's magnetic field had ___________
normal polarity
Abundant swamps led to the formation of coal during the Late Paleozoic in which of the following places?
north america
Late Paleozoic glacial deposits are not found in which continent
north america
the two big magnets of Earth's magnetic field that have a transfer of energy that make compasses work
north and south pole
The lithosphere of Earth can be bent and broken, but will not flow because it ____________.
is too cool
The balance between the weight of a mountain range and the buoyancy provided by the underlying mantle is termed ____________.
isostatic equilibrium
Tsunami
known as a seismic sea wave, is a series of waves in a water body caused by the displacement of a large volume of water
The magnetic field of Earth in the geologic past is ____________.
known to have been constant through geologic time, due to remnant magnetization of iron-rich minerals in rocks
The magnetic field of Earth in the geologic past is ____________.
known to have experienced numerous polarity reversals, due to remnant magnetization of iron-rich minerals in rocks
A fast moving flow consisting of a mixture of water and volcaniclastic debris is termed a ____________.
lahar
Orogenesis (mountain building) leads to the production of ___________
all three rock types
Within the sea floor, the rate of geothermal heat flow is greatest ___________
along mid ocean ranges
The youngest sea floor occurs ____________.
along mid ocean ridges
The youngest sea floor occurs ____________.
along mid-ocean ridges
The smoky cloud that rises from the vent of an actively erupting volcano is composed of ____________.
ash
The lithosphere lies directly above the _________
asthenosphere
part of the crust, rock, still solid but can flow
asthenosphere
Most of the pushing force driving plate motion is produced ____________.
at mid-ocean ridges
The thickness of clay and planktonic microskeletons is greatest ________
at ocean basin edges
Why are fossils found on the top of Mt. Everest?
at one point in time, the top must have been below sea level
Most of the pulling force driving plate motion is produced ____________.
at subduction zones
The thickness of clay and planktonic microskeletons is greatest ____________.
at the edges of ocean basins
The region of thermally metamorphosed rock surrounding a cooled pluton is called a(n) ____________.
aureole
A blob-like igneous rock body that has cooled beneath the surface of Earth is ____________.
pluton
intrusive activity where magma intrudes into other rocks as balloon-shaped blobs
plutons
The apparent tendency of the north (or south) magnetic pole to vary in position over time is termed ____________.
polar wander
the crust is ______ for land, and _______ for the ocean
thick, thin
Continental lithosphere is ___________ than oceanic lithosphere
thicker
Summed over the entire surface of Earth, ____________.
rates of lithospheric production and consumption are equal
asthenosphere
region of the mantle where rocks become ductile, have little strength, and are easily deformed. It lies at a depth of 100 to 350 km below the surface
Loose, weathered sediment at the surface that has not been organically altered is termed ____________.
regolith
The development of a preferred orientation of large, flaky mica crystals within metamorphic rock is termed __________
schistosity
this occurs when upwelling mantle erupts at mid ocean ridges, new crust moves away from the ridges
sea floor spreading
Most continental topography lies within a range of altitude between ____________.
sea level and 1 km above sea level
Marine magnetic anomaly belts are widest when and where ____________.
sea-floor spreading rates are relatively rapid
a body of rock affected by compressive stress will likely undergo ---------
shortening
Most abundant component in magma is:
silica
Andesitic Lava
slow-moving
Rhyolitic Lava
slow-moving. Most viscous. Coolest. Sometimes freezes in the vent forming a spire.
higher viscosity creates _____ flow
slower
Valleys and hillsides carved by glaciers are generally more ____________ in comparison to those produced by rivers and streams.
steep sided
the development of layering within sedimentary rocks is known as?
stratification
intermediate sized volcano
strato
Mt. Fuji in Japan is an example of a ________
stratovolcano
Of the three primary forms of subaerial volcanoes, ____________ are sometimes referred to as "composite volcanoes
stratovolcanoes
Of the three primary forms of subaerial volcanoes, ____________ consist of alternating layers of tephra and solidified lava.
stratovolcanoes
The color of a mineral in powdered form is termed ________
streak
Force per unit area is termed __________
stress
A body of rock affected by tensile stress will likely undergo _________
stretching
Most of the pulling force driving plate motion is produced at _________
subduction zones
Volcanoes that do not occur along either present or emergent plate boundaries are associated with ____________.
subduction zones
Pillow lavas are associated with ____________
submarine basaltic eruptions
Earth's hydrosphere consists of ____________.
surficial freshwater, the oceans, groundwater, and atmospheric water
A fold shaped like an elongate trough is a(n) ______
syncline
On a geologic map, if the contacts between sedimentary rock units form a series of parallel lines, with the youngest unit in the center, the underlying structure is a(n) ____
syncline
Deformed (bent, stretched, or cracked) lithosphere occurs on the margins of _______
tectonic plates
fragments of the lithosphere
tectonic plates
The geotherm is the rate of change of ____________ over depth in the earths interior
temperature
Variations in pressure, _________________ , and composition result in variations in density within the Earth.
temperature
______ and ______ increase with depth in the Earth
temperature, pressure
The difference between tephra and tuff is that ____________.
tephra is unlithified, whereas tuff is lithified
An island volcanic arc occurs at ____________.
the Aleutian Islands of Alaska
Oceanic lithosphere thickens away from the mid-ocean ridge primarily due to ____________.
the addition of new lithospheric mantle as a result of cooling
A triple junction is a place on Earth's surface where ____________.
the boundaries of three lithospheric plates meet at a single point
Mohorovicic discontinuity
the boundary between the earth's crust and the upper part of the Asthenosphere; seismic waves change speed at this boundary.
Solar system
the collection of eight planets and their moons in orbit around the sun, together with smaller bodies in the form of asteroids, meteoroids, and comets. An arm of the Milky Way galaxy.
Minerals in geodes form spectacular euhedral crystals because ____________.
the crystals have abundant room to grow in their hollow surroundings
Convergent Margin or Collision Zone
two colliding continental plates crumple and create a mountain range Closure of a former ocean/subduction zone Medium depth earthquakes, no volcanoes Two plates pushing into each other without an ocean. Can happen after a subduction zone subducts all the ocean
Polymorph
two minerals that have the same chemical composition but a different crystal lattice structure
Which type of magma has the greatest iron and magnesium content?
ultramafic
what is a lateral moraine?
unconsolidated material deposited along the sides of an alpine glacier. may form on top of existing alpine glaciers along the sides of the valley walls. Freeze-thaw weathering results in debris falling on top of the glacial ice, forming a ridge. As glaciers melt, this material may be deposited on the landscape as a ridge.
Tephra is __________ while tuff is ___________
unlithified, lithified
where do you expect to find bigger sediments
upstream
resistance to flow
viscosity
Substances that can be transformed to a gas at relatively low temperatures are termed ____________.
volatiles
What is the term for gasses contained within liquid rock beneath the surface of the Earth?
volatiles
When contained within magma, compouds such as H20, CO2, CH4 and SO2 are termed ______________based on the relatively low temperature at which they become a gas.
volatiles
________ have a tendency to evaporate and are stable as gases
volatiles
Surface waves (L-waves)
waves that travel along Earth's outer layer (mostly up and down motion).
Secondary Waves (S-Waves)
waves that travel outward from an earthquke's focus and move through Earth by causing particles in rocks to vibrate at right angles to the direction of the wave. Can't travel through fluids. Shearing.
Anticline/Syncline pair
wavy has both anticline and syncline alternating Ductile deformation
At the surface, potassium feldspar reacts with water to form clay; this is an example of ___________
weathering
The breakdown of exposed rock into small fragments and dissolved ions is termed ____________.
weathering
Ash and lava fragments that cascade down the sides of a volcano eventually settle and lithify to form ____________.
welded tuff
what is the rupture front?
where fault slippage begins at the focus and spreads across a fault surface : travels at roughly 3 kilometers per second for earthquakes in the crust.
what is a shadow zone?
where the liquid outer core flows down p waves and stops s waves
As compared to a slowly spreading mid-ocean ridge, a rapidly spreading ridge is ___________
wider
As compared to a slowly spreading mid-ocean ridge, a rapidly spreading ridge is ____________.
wider
Hot spots can occur ____________.
within either continental or oceanic plates
The internal ordering of mineral crystals is detected using ____________.
x ray diffraction
The internal ordering of mineral crystals is detected using _________
x-ray
One Spin
~40,000 km/day or ~1700 Kph (1040 Mph), rotation centerd on Polaris, the North Star
Stretched Waves
Longer wave length/lower frequency
the outer core is _______
liquid
What are the two types of surface waves:
Love waves Rayleigh waves
Crust
Low density silicates Lithosphere
Rocks in Ohio
Lots of shale (shallow sea evidence) - 375 mya Limestone Little Sandstone
How much salt is usually present in oceans?
3.5%
Lithosphere
A rigid layer made up of the uppermost part of the mantle and the crust.
Crystalline rocks
grains interlock with one another like pieces of a jigsaw puzzle
The intrusive compositional equivalent of rhyolite is
granite
The intrusive compositional equivalent of rhyolite is .
granite
a neutral atom that loses an electron becomes an
cation
The smallest detrital grains are ____________.
clay
The central portion of high curvature on a fold is termed the fold ________
hinge
melt at the surface
lava
Outer core
liquid iron and nickel sulfur, 2255 km thick, density 10-12 g/cm^3
a process that transforms loose sediments into solid rock
lithification
What does a planet with flat surface indicate?
Active volcanism Hotter
All basalts younger than 700,000 years old have ___________ magnetic polarity
normal
Types of volcanoes
shield, cinder cone, composite (stratovolcano).
Two distinct minerals may have the same chemical formula.
true
What are the three kinds of plate boundaries?
Divergent, convergent, transform
Basalt (Gabbro)
Dominant rock in oceanic crust. Dark colored. Low silica.
Evidence for a united Pangaea comes from the fossil record of which type(s) of organisms?
all of the above
Hot-spot volcanoes ____________.
all of the above
In silicate minerals, tetrahedra may be coordinated to form ____________.
all of the above
Describe Siccar Point unconformity in Scotland.
1. Grey sandstone is deposited honrizontal and flat. 2. Folding of grey sandstone 3. Erosion of grey sandstone 4. Deposition of "Old Red Sandstone", the youngest rock. 5. Folding of the rocks together
What are the three principles that determine relative age?
1. Original horizontality 2. Stratigraphic superposition 3. Cross-cutting relationships
Pahoehoe ____________.
all of the above
Moon (distance)
1.3 Light seconds (237,000 miles away)
Earthquakes at midocean ridges occur only in the first _____ km beneath the seafloor and tend to be ______.
10 km, small
Two continents are spreading apart at a rate of 2 centimeters per year. A this rate, at what distance, to the nearest kilometer, from the mid ocean ridge will the ocean crust be 10 million years old? (enter a numeric answer only, without units)
100
A mid-ocean ridge is spreading at 2 centimeters per year. What's the age of the ocean floor 100 kilometers from the ridge? Enter your answer to the nearest millions of years.
10000
Quakes deeper than ______ km are more likely associated with ______ caused by stresses within the slab.
100km, faults
Rounding to the nearest integer, the density of the inner core is approximately _________________ grams per centimeter cubed. (numeric answer only)
13
Edge of the visible universe
13 billion light years away
Renaissance Era
1400's Europe new aged discoveries. Copernicus, Galileo, Newton
What's the Earth's average atmospheric pressure at sea level to nearest pound per square inch?
15
How far away was the Virginia earthquake felt?
150 Miles from the epicenter
The average thickness of continental lithosphere is about _________
150 km
Speed of light
186,000 miles per second or 300,000 kilometers per second
The oldest basalts on the ocean floor are about ____________ years old
200 million
The oldest basalts on the ocean floor are about ____________ years old.
200 million
How many directions of cleavage are indicated in the diagram?
3
Rounded to the nearest integer, the average density of the Earth's crust is __________ grams per cubic centimeter. (numeric answer only)
3
The metallic content of Earth's core is ____________.
all of the above
Most common rocks begin to melt at _____ C
800
A marine magnetic anomaly is located 20 km from the mid ocean ridge and is 1 million years old. What is the spreading rate in centimeters per year? (enter a numeric answer only, without units)
4
How many oxygen ions are involved in the formation of the silicon-oxygen tetrahedron?
4
Rounding to the nearest integer, the inner core is ___________ times more dense than the crust on average. (numeric answer only)
4
Terrestrial Planets
4 most inner planets. (Mercury, Venus, Earth, Mars )
Gas giant planets
4 outermost planets (Jupiter, Saturn, Uranus, Neptune)
Age of our solar system
4.6 billion years~ Earth 5.0 billion years~ Sun 4.6 billion years~ oldest meteorite 4.2 billion years~ oldest minerals
How thick is continental crust?
40 km
Visible wavelength
400-700 nm Red Waves 700 (lower frequency) Blue Waves 400 (higher frequency)
Continental Crust thickness
45km thick thicker than oceanic bc less dense Lighter relatively = stands higher above sea level
Chemical composition of earth's crust
46.6% oxygen 26.72% silicon 8.13% aluminum 5.0% iron 3.63% calcium 2.83% sodium 2.59% potassium 2.09% magnesium
Magnitude of Virginia Earthquake:
5.8
Continental crust is typically 35 km thick, but may be up to ____________ thicker under mountain ranges.
50%
What is the depth of the Virginia earthquake?
6 km / 4 mi
How fast to P waves move?
6 km/s at the crust 8 km/s in the upper mantle
What is the radius of the Earth to the nearest 100 kilometers? (enter number only, without units)
6400
The Wadati-Benioff zone extends down within the mantle to a maximum depth of ____________.
670 km
The thickness of Earth's crust varies from ____________.
7 to 70 km
The thickness of Earth's crust varies from _______ km
7-70
Earth's surface
70% water, 30% land.
Compostion of Earth's Atmosphere
78.08% Nitrogen 20.95% Oxygen 0.97% other gases
How thick is oceanic crust?
8-10 km
Sun
8.3 light seconds (93 million miles away)
Dynamothermal (regional) metamorphism occurs when ____________. a. rock becomes buried deeply during continental collision and mountain building b. regression of the sea leads to erosion of sedimentary cover atop a body of rock c. the upper surface of a body of rock develops a thick soil profile d. a pluton causes metamorphism in a small surrounding region
A
Rhyolitic lavas ____________. a. do not flow as far from the vent as basaltic lavas do b. cool much more slowly than basaltic lavas do c. are associated with volcanoes that almost never emit pyroclastic debris d. all of the above
A
Volcanic bombs are ____________. a. pyroclastic blocks that acquire aerodynamic shapes during flight out of the volcanic vent b. explosive bodies of lava with high volatile content c. cinders that explode upon impact with the ground d. used by geologists to set off small eruptions in volcanoes that are deemed potentially dangerous
A
Alfred Wegener
A German scientist who proposed the theroy of continental drift. (1912)
Dinosaur Extinction Theory
A NEO (near Earth object) or a volcanic eruption killed dinosaurs.
In the diagram below, two positive (black) marine magnetic anomalies are labeled A and B. Based on the diagram, which of the following statements is correct?
A and B are of the same age.
What is a compressional wave?
A body wave that consists of alternating pulses of contractions and expansion. These can deform rocks.
Protostar
A contracting cloud of gas and dust with enough mass to form a star
Blue shift
A decrease in the wavelength of radiation emitted by an approaching celestial body.
What does a thick lateral moraine signify?
A deep glacier
Inner core
A dense sphere of solid iron and nickel at the center of Earth
Atmosphere
A mixture of gases (volcanic gases and materials from comets) that surrounds a planet or moon.
Heliocentric
A model of the solar system in which Earth and the other planets revolve around the sun
Geocentric
A model of the universe in which Earth is at the center of the revolving planets and stars.
Elements
A molecule composed of one kind of atom; cannot be broken into simpler units by chemical reactions.
Peer Review
A process by which the procedures and results of an experiment are evaluated by other scientists who are in the same field or who are conducting similar research. Vigorous review that usually rejects the work. Very important in making sure any published work is thoroughly vetted, valid Can reject, update, throw out scientific works
Formation of the Moon
A small planentoid collides with earth. The debris forms a ring which compacts into the moon.
Moon
A solid body locked in orbit around a planet
Reversed polarity
A state in which magnetized objects would reverse direction and orient themselves to point south.
Meteor
A streak of light in the sky produced by the burning of a meteoroid in Earth's atmosphere.
Pangea
A supercontinent containing all of Earth's land that existed about 225 million years ago.
Convergent boundary
A tectonic plate boundary where two plates collide, come together, or crash into each other.
Theory of Plate Tectonics
A theory stating that Earth's lithosphere is broken into huge plates that move and change in size over time.
Plate tectonics
A theory stating that the earth's surface is broken into plates that move. Unifies all of geology and explains the formation and location of volcanoes, earthquakes, ocean basins, mountains, other surface features, the ages of rocks, as well as the patterns of plant and animal evolution.
Crystal Lattice
A three-dimensional geometric arrangement of particles
Normal fault
A type of fault where the hanging wall slides downward; caused by tension in the crust Pulling apart
Normal fault
A type of fault where the hanging wall slides downward; caused by tension in the crust.
Reverse fault
A type of fault where the hanging wall slides upward; caused by compression in the crust.
Sun
A typical star that is the source of light and heat for the planets in the solar system. May be third, fourth, or fifth generation star.
basalt with a jagged, sharp, angular texture. forms when lava moves fast and/or cools fast
A'a' lava
The eruption temperature of basalts is _________ whereas rhyolitic lavas are erupted at _______ temperature A. 1160 C, 900 C B. 150 C, 100 C C. 10,500 C, 7,500 C D. 610 C, 450 C
A. 1160 C, 900 C
Starting in the early 1800's, how have we known that the rocks deep inside the earth are not the same as the rocks that we find at the surface of the earth? A. B/c the rocks that we find at the earth's surface have a density that when multiplied by the volume of the earth yields a mass less than the total mass of the earth B. B/c the rocks that we find at the earth's surface have a density that when multiplied by the volume of the earth yields a mass greater than the total mass of the earth C. Because the earth has a spherical shape D. Because erupted lavas from volcanoes have a chemistry that differs from other crustal rocks
A. B/c the rocks that we find at the earth's surface have a density that when multiplied by the volume of the earth yields a mass less than the total mass of the earth
Why is the oldest oceanic crust generally not older than 200 million years? A. Because oceanic crust older than 200ma is too dense to remain on top of the mantle B. Because subduction zones at geographically located such that no oceanic crust can be older than 200 ma C. This statement is false D. Because oceanic crust older than 200ma becomes attached to more buoyant continental crust
A. Because oceanic crust older than 200ma is too dense to remain on top of the mantle
In the above graphic, the pink + signs represent tsunami run-up events that have occurred over the previous 4,000 years. Why does there appear to be fewer tsunami run-up events along the eastern coast of South America compared to its western coast? A. Because the large earthquakes that generate tsunamis generally occur more often in the Pacific basin than in the southern Atlantic basin B. Because subduction zones produce tsunamis, whereas mid-ocean ridges do not C. Because tsunamis require a bathymetric to shoreline profile that abruptly shifts from deep to shallow D. None of the above
A. Because the large earthquakes that generate tsunamis generally occur more often in the Pacific basin than in the southern Atlantic basin
From 2008 to 2014, did the eastern coast of the U.S. experience an increased risk for earthquakes? A. No, the apparent increased risks are merely a result of mapping algorithms and not a result of changing tectonic forcing B. No, as with anything reported in the media, we can ignore it C. Yes, with the mapping evidence of changing tectonic stresses clearly indicates increased risks D. None of the above
A. No, the apparent increased risks are merely a result of mapping algorithms and not a result of changing tectonic forcing
Imagine that you have landed on a planet and have five seismometers. You have noticed a cluster of earthquakes occurring in one particular location. Where would you place these seismometers in order to understand the planet's deep interior crust?
A. Place the five seismometers in a line, with the first seismometer located the closest to the cluster of earthquakes, the second further away, and so on until the fifth one is placed the greatest distance away
The hypothesis that the Earth has a spherical structure with layers (e.g. crust, mantle, core) of differing physical and chemical properties is based on A. seismic wave phases such as P, PP, PKP, PcP, etc B. deep drilling projects with bore holes on several continents C. the temperature of volcanic lavas and the associated gravitational field D. none of the above
A. Seismic wave phases such as P, PP, PKP, PcP, etc.
The eruption of Mt. St. Helens was more violent than Hawaii's eruptions because A. St. Helens was an andesitic to rhyolitic lava in composition B. St. Helens was a basaltic lava in composition C. St. Helens is associated with a hotspot D. St. Helens is named for a violent person
A. St. Helens was an andesitic to rhyolitic lava in composition
The youngest sea floor occurs A. along mid-ocean ridges B. along active margins C. along passive margins D. randomly distributed over the entire ocean basin
A. along mid-ocean ridges
The formation of the earth resulted in A. an initially hot planetary interior that is now kept hot by radioactive decay B. an initially hot planetary interior that is now kept cool by radioactive decay C. an interior made up of two basic layers differentiated by chemical composition D. an interior made up of three basic layers with the same chemical compositions
A. an initially hot planetary interior that is now kept hot by radioactive decay
In the graphic above, what is the geologic evidence for subduction between the Tethys Ocean and the southern margin of Eurasia and Indochina (i.e. the subduction is indicated by the line with orange triangles)? A. andesitic rocks B. basalt rocks C. limestones D. granite rocks
A. andesitic rocks
Why is northwest Ohio flat and southeast Ohio hilly?
A. because continental scale glaciers covered northwest Ohio but not southeast Ohio
Based on climate model simulations, the temperature of Europe will __________ if thermohaline circulation collapses A. decrease B. increase C. remain the same d. none of the above
A. decrease
From 1978 to 2015, Arctic sea ice is ____ and Antarctic sea ice is ____ and globally the sum of both is
A. decreasing in extent, increasing in extent, decreasing in extent
Andesitic to Rhyolitic lavas A. do not flow as far from the vent as basaltic lavas do B. have a higher eruption temperature than basaltic lavas C. are associated with volcanoes that have a low silica content D. all of the above
A. do not flow as far from the vent as basaltic lavas do
At transform plate boundaries, for example between two mid-ocean ridges or the San Andreas Fault in California, A. earthquake are common, but volcanoes are not common B. volcanoes are common, but earthquakes do not occur C. both earthquakes and volcanoes are common D. earthquakes are amongst the deepest and most destructive on earth
A. earthquake are common, but volcanoes are not common
What age does radiometric dating give?
Absolute age
The travel path of a seismic wave from the focus, into the body of the earth, and to the seismometer 5,000km away A. is curved b/c of refraction B. is curved b/c of reflection C. is straight because of refraction D. is straight because of reflection
A. is curved b/c of refraction
The types of rocks we would expect to find while walking along an outcrop in Florida are ___________ whereas in Ohio we should find A. limestone; sedimentary rocks (shale, limestone) B. granite; sedimentary rocks (shale, limestone) C. sedimentary rocks (shale, limestone); granite D. sedimentary rocks (shale, limestone); basalt
A. limestone; sedimentary rocks (shale, limestone)
Imagine that you and your research team have measured earthquakes that have occurred at your study site. You find that the earthquake depths extend from near the earth's surface to almost 700 km depth. You conclude that you have found a A. subduction zone B. spreading center (e.g. rift zone) C. convergent plate margin between two continental plates D. none of the above
A. subduction zone
A property of rocks that enhances mantle convection is A. that a 1 percent expansion requires an increase of 300-400C and leads to a 1 percent decrease in density B. that a 50 percent expansion requires an increase of 300-400C and leads to a 50 percent decrease in density C. that a 1 percent expansion requires an increase of 1300-1400C and leads to a 1 percent increase in density D. that no expansion of the rock occurs
A. that a 1 percent expansion requires an increase of 300-400C and leads to a 1 percent decrease in density
Earthquakes in Ohio occur because A. the build-up of stress has exceeded the local rock strength B. of the abundance of basaltic rocks C. ground accelerations exceed the force of gravity D. the San Andreas Fault has become locked
A. the build-up of stress has exceeded the local rock strength
The basic form of the continuity equation expresses
A. the difference between the amount of water flowing into and out-of a given location and equates this to the volumetric change in water for that location
Alpine glaciers always flow down the topographic slope, so why does the end of the glacier actually retreat back up the valley? Because ___________ A. the mass of snow being added is less than the amount of ice being melted B. the mass of snow being added is greater than the amount of ice being melted C. the mass of rocks being carried in the glacier exceeds its carrying capacity D. the mass of rocks being carried in the glacier is less than its carrying capacity
A. the mass of snow being added is less than the amount of ice being melted
Basalt
AKA Gabbro Oceanic crust and eruption (midocean, hot spots in ocean) Low silica content
Granite
AKA Rhyolite High silica content Slower the cooling, larger the crystals
Lithosphere
AKA crust Cold, hard, brittle rock compared to mantle 0-100km deep Heat moves primarily by conduction Too cold for ductile flow/convection Brittle, cold rock
Dwarf planet
An object that orbits the sun and is spherical, but has not cleared the area of its orbit.
Doppler effect
An observed change in the frequency of a wave when the source or observer is moving
Structure (Cosmology)
Ancient Greeks thought it was Geocentric
Subducting plate Fractionation leads to
Andesite, higher viscosity, steep volcano, sticky cooler lava
What direction does a seismic wave travel?
Any direction
Model:
Are constrained by or designed to match observations
Second generation stars
Are formed after heavy elements were made inside other previous stars.
Hotter materials
Are less dense
Colder Materials
Are more dense
Delta
Area of deposition Flat
Hot spots
Area of volcanic activity, not at a plate boundary. Hot spots are caused by rising plumes of hot mantle material. These mantle plumes remain stationary for long periods of geologic time.
Conglomerate
Area prone to flooding carries larger pieces of sedimentary rock into a layer, pattern of layers of smaller and larger pieces Silt/Gravel alternating
A clastic rock comprised of sand-sized grains derived from the physical weathering of granite and containing a sizable proportion of feldspar is termed ____________.
Arkose
Normal, reverse, and thrust are all examples of ____________ faults. a. strike-slip b. dip-slip c. oblique-slip
B
Phreatomagmatic eruptions take place when ____________. a. volatiles effervesce prior to lava flow b. water enters the magma chamber and forms steam c. basaltic lava clogs the chimney d. lava or pyroclastic debris erupt by bursting through the sides of the volcano
B
The distinction between joints and faults is that ____________. a. faults are joints that are greater than one square meter in areal extent b. faults are fractures along which displacement has occurred; displacement does not occur along joints c. joints are fractures along which displacement has occurred; displacement does not occur along faults d. there is no distinction; the two terms are synonymous
B
Thermal (contact) metamorphism produces ____________. a. foliated rocks only b. nonfoliated rocks only c. both foliated and nonfoliated rocks
B
Which soil horizon is the zone of accumulation, so named because dissolved matter, leached from other parts of the soil, precipitates to form new minerals
B horizon
If the ratio of daughter to parent atoms in a rock is 93.75 to 6.25 and the half-life of decay is 10 million years, how many half-lives have occurred since the rock was formed and how old is the rock? A. 4, 20 million years old B. 4, 40 million years old C. 5, 25 million years old D. 5, 50 million years old
B. 4, 40 million years old
Climate model simulations for the Arctic during September of the years 2040 to 2059 suggest that ______ which as important consequences for __________ A. Arctic sea ice will decrease in extent compared to today; sea level rise from the melted sea ice B. Arctic sea ice will decrease in extent compared to today; transportation and navigation C. Arctic sea ice will have the same extent as compared to today; thermohaline circulation D. Arctic sea ice will increase in extent compared to today; fisheries and related ecologies
B. Arctic sea ice will decrease in extent compared to today; transportation and navigation
This rock is found in Sunbury, Ohio just a few miles north of Columbus. It is a granite. Which of the following can you reasonably conclude? A. The rock formations around Sunbury, Ohio are all granite B. At some time in the past, the average annual temperature of Ohio must have been less than zero degrees Celsius C. A large flood covered this location at some time in the past D. All of the above
B. At some time in the past, the average annual temperature of Ohio must have been less than zero degrees Celsius
How was the Tibetan Plateau formed (reminder: it is located just north of the Himalaya Mountains)? A. By the collision of India with Africa B. By the successive accretion (i.e. joining or suturing) of various terrains to Asia C. By the collision of Africa with Asia D. by the successive subduction of various terrains splintered away from Africa
B. By the successive accretion (i.e. joining or suturing) of various terrains to Asia
In the March 11, 2011 Japan earthquake, why did the land move about 4m laterally and about 0.5m vertically? A. Strike-slip faulting caused the plates to become locked B. The crust elastically rebounded after the earthquake released the built-up strain C. the subducting plate created volcanic magma that pushed the crust and land surface D. Liquification caused the land to subside
B. The crust elastically rebounded after the earthquake released the built-up strain
Most of the pulling force driving plate motion is produced A. at mid-ocean ridges B. at subduction zones C. at collision zones D. in the interiors of continental plates
B. at subduction zones
Earthquakes cause ________ and nuclear explosions cause ____________ in a focal mechanism A. compressional upward P-wave first motions in 4 quadrants, compressional upward P-wave first motions in 2 quadrants B. compressional upward P-wave first motions in 2 quadrants, compressional upward P-wave first motions in 4 quadrants C. No P-wave first motions, only P-wave first motions D. only P-wave first motions, no P-wave first motions
B. compressional upward P-wave first motions in 2 quadrants, compressional upward P-wave first motions in 4 quadrants
Regional climate models suggest that water flowing off Greenland's ice and into the ocean during June is ________ the amount of measured water flowing in Greenland's rivers that drain to the ocean. This implies that _______
B. greater than; models may over-predict the amount of sea level rise
Greenland's ice measured over time from the GRACE satellites ...
B. has an increasing mass in the zone of accumulation and has a decreasing mass in the zone of ablation, and combining the zones, all of Greenland's ice is losing mass
Ocean density, salinity, and temperature A. change mostly in the lower depths of the ocean B. increases, increases, and decreases from the surface to about 500m depth C. increases, decreases, and increases from the surface to about 500m depth D. increases, decreases, and decreases from the surface to about 500m depth
B. increases, increases, and decreases from the surface to about 500m depth
The crustal root beneath mountains created by continent-continent collision is _____________ when compared to the root beneath rifted terrains A. smaller B. larger C. the same size as D. none of the above
B. larger
Most continental topography lies within a range of altitude between A. sea level and 1 km below sea level B. sea level and 1 km above sea level C. 1 to 2 km above sea level D. 2 to 4 km above sea level
B. sea level and 1 km above sea level
At what depth did the deformation in the photo occur? A. at the earth's surface B. well within the crust C. at the crust-mantle boundary D. In the upper mantle
B. well within the crust
Stars
Ball of incandescent gas, nuclear fusion reaction
What rocks are oceans made up of?
Basalt
What type of rocks do Rift Volcanoes form?
Basalts
How did scientists conclude that the crust split?
Because of the symmetric magnetic pattern
GPS Campaign
Bedrock reference points checked semi frequently to tell movement of plates
Long period comets
Believed to originate at a much greater distance from the Sun, in a cloud (the Oort cloud) consisting of debris left over from the condensation of solar nebula. Comets are thrown from the outer planets or nearby stars, or as a result of collisions.
Asteroid belt
Between Jupiter and Mars
Inactive fracture zone
Beyond offset ridges plates move in the same direction.
Compared to low-grade metamorphic rocks, high-grade rocks ____________. a. always contain more quartz and feldspar b. are produced closer to the surface, high in the stratigraphic column c. are produced at greater temperatures and pressures d. are produced at cooler temperatures, but greater pressures
C
Dynamothermal (regional) metamorphism produces ____________. a. foliated rocks only b. nonfoliated rocks only c. both foliated and nonfoliated rocks
C
Hot-spot volcanoes ____________. a. can arise from the ocean floor b. can arise on continents c. may arise in the interior of lithospheric plates d. all of the above
C
It is possible for offset along an oblique-slip fault to have both ____________ components. a. normal and reverse b. right-lateral and left-lateral c. normal and left-lateral
C
Spheroidal weathering occurs when ____________. a. physical weathering predominates and there is little chemical weathering b. physical weathering breaks boulders directly into spherical cobbles and pebbles c. chemical weathering attacks corners and edges of rock more rapidly than its interior d. chemical weathering works at a uniform rate throughout the rock
C
Which soil horizon is chemically most similar to the underlying bedrock or unaltered sediment?
C horizon
When considering all earthquakes around the world per year, earthquakes with a magnitude of 2 occur _________ as earthquakes of a magnitude 6 A. about the same number of times B. about twice as often C. 10,000 times more often D. 10,000 times less often
C. 10,000 times less often
When considering typical ocean salinity, "salts" such as chlorides and sodium, make up _____ and are a result of _______
C. 3.5% of ocean water volume; runoff from the continents delivering dissolved ions to the oceans
The age of the Earth is approximately ________ which is determined by ______? A. 15 billion years, red shifts in the light spectrum B. 15 billion years, gravitational forces from black holes C. 4.6 billion years, radiometric dating D. 4.6 billion years, fossil evidence
C. 4.6 billion years, radiometric dating
A seismogram with a P minus S travel time difference of 8 minutes is recorded from a seismometer located A. 20 degrees from the earthquake B. 40 degrees from the earthquake C. 60 degrees from the earthquake D. Not possible to determine
C. 60 degrees from the earthquake
Transgression and regression of the oceans upon the lands, typically yields A. Stratigraphically alternating sequences of sandstones, granites, and basalts B. Stratigraphically alternating sequences of sandstones granites, and gneiss C. Stratigraphically alternating sequences of sandstones, shales, and coals D. Stratigraphically alternating sequences of sandstones, conglomerates, and coals
C. Stratigraphically alternating sequences of sandstones, shales, and coals
The above graphic is a bathymetric map of the Hawaiian hotspot. Choose the following that is most correct using this graphic (North is at the top of the graphic). A. The magma plume is moving northwest B. The magma plume is moving southeast C. The plate is moving northwest D. The plate is moving southeast
C. The plate is moving northwest
Imagine you are at a rock outcrop and see a stratigraphic sequence of silts and gravels. What do you think is the most likely process that produced this sequence of rock? A. transgression and regression of the oceans on the lands B. a series of volcanic eruptions like that of Mt. St. Helens C. a river with intervals of normal water flow interleaved with flooding D. the subduction of an oceanic plate beneath a continental plate
C. a river with intervals of normal water flow interleaved with flooding
Using the photo above, what type and rocks and plate setting might you expect were involved in the formation of this mountain? A. basaltic rocks; rifting of two plates B. basaltic rocks; movement of a plate over a hotspot C. andesitic to rhyolitic rocks; subduction of an oceanic plate beneath a continental plate D. andesitic to rhyolitic rocks; collision of two continental plates
C. andesitic to rhyolitic rocks; subduction of an oceanic plate beneath a continental plate
Alpine glaciers around the world A. have an ice mass that is essentially in balance B. have growing accumulation zones, thus moving forward C. are melting and receding D. are not significant indicators of climate change
C. are melting and receding
In science, models and/or theories A. prove the existence of plate tectonics and the core of the earth B. prove that the crust is more buoyant than the mantle C. are proven to be true or false based on measurements, observations, and/or the results of experiments D. are widely accepted by fellow scientists
C. are proven to be true or false based on measurements, observations, and/or the results of experiments
Given two earthquakes in the same location in California and a seismometer located here in Ohio: a magnitude 6 earthquake produces P-waves that arrive here __________ P-waves from a magnitude 8 earthquake A. slower than B. faster than C. at the same time as D. none of the above
C. at the same time as
Fractionation is a process A. by which melt separates from solid rock as temperature increases; the remaining solid rock has a higher melting temperature than before fractionation B. that creates rocks which are different from the original rock C. both A and B D. Neither A nor B
C. both A and B
Regions of earthquake risks A. occur mostly at plate boundaries B. can occur within plates C. both A and B D. neither A nor B
C. both A and B
The type of a fault in California can be remotely determined, without having to actually visit the fault. This is done on active faults and with seismometers not located in California A. b/c the seismometers record first motions which represent motions along the fault B. b/c seismometers are located around the world C. both A and B D. none of the above
C. both A and B
The Andes Mountains and the Himalaya Mountains A. are a result of plate rifting B. are like all mountains, both are made up of granitic rock C. differ in their plate tectonic settings and thus the mountains are made-up of different rocks D. are similar in their plate tectonic setting and thus the mountains are made-up of similar rocks
C. differ in their plate tectonic settings and thus the mountains are made up of different rocks
As compared to the density of the mantle, the oceanic crust is A. always more dense B. always less dense C. initially less dense when it is formed, but eventually becomes more dense D. initially more dense when it is formed, but eventually becomes less dense
C. initially less dense when it is formed, but eventually becomes more dense
At a subduction zone, the overriding plate A. is always composed of continental lithosphere B. is always composed of oceanic lithosphere C. may be composed of either oceanic or continental lithosphere D. is composed of granite
C. may be composed of either oceanic or continental lithosphere
The correct sequence of events that led to the displayed rock strata is A. new gray sandstone deposited; erosion causing the unconformity and deposition of old red sandstone, folding of new gray sandstone, folding of old red sandstone B. new gray sandstone deposited, erosion causing the unconformity and deposition of old red sandstone; folding of new gray sandstone C. new gray sandstone deposited; new gray sandstone folded; erosion causing unconformity and deposition of old red sandstone; slight folding of all rock layers D. new gray sandstone deposited; new gray sandstone folded; erosion causing the unconformity and deposition of old red sandstone; folding of only old red sandstone
C. new gray sandstone deposited; new gray sandstone folded; erosion causing unconformity and deposition of old red sandstone; slight folding of all rock layers
The seismic shadow zone of the Earth, which is an indication that the outer core is liquid, A. occurs near seismically active regions B. occurs approximately 100km from active faults C. occurs about 100 to 180 degrees from any earthquake D. occurs about 100 to 180 degrees from subduction zone earthquakes
C. occurs about 100 to 180 degrees from any earthquake
The picture is an example of A. normal faulting B. reverse faulting C. right-lateral strike-slip fault D. left-lateral strike-slip fault
C. right-lateral strike-slip fault
In the above photo, the ice in the glass is floating such that a small portion of the ice is above the water line and a much greater amount of ice is within the water. To raise more of the ice above the water line A. the water density should be less than it is now B. the ice density would need to be greater than it is now C. the ice density would need to be lesser than it is now D. none of the above
C. the ice density would need to be lesser than it is now
Summed over the entire surface of the Earth, A. the rate of lithosphere production at mid-ocean ridges is greater than the rate of lithospheric consumption at subduction zones B. the rate of lithospheric consumption at subduction zones is greater than the rate of lithospheric production at mid-ocean ridges C. the rates of lithospheric production at mid-ocean ridges and consumption at subduction zones are equal D. None of the above
C. the rates of lithospheric production at mid-ocean ridges and consumption at subduction zones are equal
Imagine that instead of looking at ice in water, you were looking at a rock in magma. Assume that the rock solidified from the magma. What do you expect to happen next? To answer this question, you can think of the water in the glass as liquid magma, and the ice as the solid rock derived from the magma. A. the rock would extend higher above the magma as proportionally compared to the position of the ice in the water B. the rock would sit in the magma at about the same proportion depth as the ice sits in the water C. the rock would sink to the bottom of the magma D. none of the above
C. the rock would sink to the bottom of the magma
How many seismic stations are needed to determine the location of an earthquake? A. Only one B. just two C. three or more D. None, seismic stations cannot be used to determine earthquake locations
C. three or more
What do you do if the model doesn't match measurements?
Change the model
What are models?
Changeable and temporary based on facts and observations.
Types of sedimentary rocks
Clastic, Biochemical, Organic, Chemical
Alpha Centauri
Closest star (4.3 light years away)
Rocks in Florida
Coastal, lots of Limestone
Mars
Cold (-64°F) and Dry
Mineral identification
Color, streak, luster, Hardness (moh's scale), specific gravity, crystal habit, crystal form, fracture, cleavage
If the wave in a seismogram is up first, what type of earthquake is it?
Compression earthquake
Why convection?
Conduction works, but rocks are poor conductors of heat. Rock stays hot.
As compared to the rocks that make up the crust, Earth as a whole is ____________
Considerably more dense
Hot spots can only occur in ____________ plates
Continental
Ophiolite sequences are important to geologists because they preserve ____________.
Continental Crust
What is not recycled into the mantle.
Continental Crust
Which type of crust is not recycled into the mantle?
Continental because it is light and less dense.
Name the three main parts of Earth's Interior
Core, mantle, crust.
What is the role of fossils in determining the Earth's geologic history?
Correlating strata
How was the Earth's geologic history created?
Correlating stratigraphic records
Fusion
Creation of energy by joining the nuclei of two hydrogen atoms to form helium.
Earth's layers
Crust, mantle, core (inner and outer)
Crystal shapes
Cubes, Octahedra, Blades, Hexagonal Prisms, Dodecahedral, Compound forms, Rhombohedra, Tetragonal Prisms
Deformation brought on by orogeny can ____________. a. metamorphose rock b. produce folds in rock c. produce faulting in rock d. all of the above
D
Pahoehoe ____________. a. forms when basaltic lava flows cease flowing and solidify simultaneously b. has a smoother texture than aa c. is easier to walk on than aa is d. all of the above
D
Oceans and the salinity causing process have existed for at least a billion years, so why are the oceans not more salty than the amount noted in question 29? A. B/c some biological processes such as the formation of shells by organisms remove salts from the ocean B. B/c some chemical reactions of basalt with ocean water removes salts C. B/c some salts are deposited with sediments at the bottom of the ocean D. All of the above
D. All of the above
In the photo above, why is the vegetation only toward the middle of the island and not spread across the entire island, i.e. why is there brown, non-vegetated soil? A. Because the prevailing wind patterns preferentially remove seedlings that could have potentially provided vegetative growth over the brown areas B. Because a tsunami washed away the vegetation that used to be growing on the brown areas C. Because this is an example of island deforestation D. Because an earthquake occurred, which released pent-up strain that had pulled the island down into the ocean during plate motion and that after the earthquake allowed the island to rebound to a position that now lies above the water level, i.e. the brown, non-vegetated soil was below sea level prior to the earthquake
D. Because an earthquake occurred, which released pent-up strain that had pulled the island down into the ocean during plate motion and that after the earthquake allowed the island to rebound to a position that now lies above the water level, i.e. the brown, non-vegetated soil was below sea level prior to the earthquake
Why does the Earth not use conduction to move heat from the deep interior to the surface? A. Because brittle solid crust easily transports heat B. Because brittle solid crust does not easily transport heat C. Because rocks are very good conductors of heat D. Because rocks are very poor conductors of heat
D. Because rocks are very poor conductors of heat
Why are oceans salty?
Dissolved ions from erosion and hydrothermal vents
We know that the earth's outer core is liquid because A. surface waves refract in the outer core B. surface waves reflect off of the outer core C. S-waves are transmitted through the outer core but not P-waves D. P-waves are transmitted through the outer core but not S-waves
D. P-waves are transmitted through the outer core but not S-waves
When tracing a fault from the surface into the depths of the crust, where will it likely end? A. Where hydraulic fracturing has occurred. B. In an igneous basement rock C. Within 3km of the Earth's surface D. At the transition from brittle crust to ductile crust
D. at the transition from brittle crust to ductile crust
Voluminous eruptions may cause the volcano to collapse upon the floor of the now empty magma chamber, producing a broad depression termed a _________ (i.e. a depression like the one in the photo above) A. crater B. lahar C. fissure D. caldera
D. caldera
Thermohaline circulation A. can be driven by deep waters rising in the North Atlantic and takes 100 years to circulate throughout all oceans B. can be driven by deep waters rising in the North Atlantic and takes 1000 years to circulate throughout all oceans C. can be driven by surface waters sinking in the North Atlantic and takes 100 years to circulate throughout all oceans D. can be driven by surface waters sinking in the North Atlantic and takes 1000 years to circulate throughout all oceans
D. can be driven by surface waters sinking in the North Atlantic and takes 1000 years to circulate throughout all oceans
Most continental topography lies within the range indicated in question 12 because A. continental crust is composed mostly of basalt which is less dense than the underlying asthenosphere and mantle B. continental crust is composed mostly of basalt which is less buoyant than the underlying asthenosphere and mantle C. continental crust is composed mostly of granite which is more dense than the underlying asthenosphere and mantle D. continental crust is composed mostly of granite which is more buoyant than the underlying asthenosphere and mantle
D. continental crust is composed mostly of granite which is more buoyant than the underlying asthenosphere and mantle
The Earth's geologic history can be determined by correlating strata from one continent to another using A. rock layers made up of limestones which are always from the same environment of deposition and thus correlates across the globe B. rock layers made up of shales which are always from the same environment of deposition and thus correlates across the globe C. fossils from a single species that existed for 100s of millions of years and which is found in many formations around the globe D. fossils from a couple of species that coexisted for a few million years and which are found in only a few rock formations around the globe
D. fossils from a couple of species that coexisted for a few million years and which are found in only a few rock formations around the globe
In the photo at left, how did this mountain peak form? A. from wind and stream erosion B. by subduction and fractionation C. by the progressive accretion of end moraines D. from the coalescing of at least three glacial cirques
D. from the coalescing of at least three glacial cirques
Arguably, the most important part of the scientific method and its hypothesis testing is A. the discovery process funded exclusively by the public and tax payer dollars B. the discovery process by an individual researcher who publishes an incremental amount C. peer review by the public via the reading of media reports about a particular discovery D. peer review by many other experts in the particular field of study
D. peer review by many other experts in the particular field of study
Marine magnetic anomaly stripes are oriented parallel to mid-ocean ridges and are observations supporting A. continental drift B. fracture zones C. continental shelves D. plate tectonics
D. plate tectonics
Which seismic wave types cause the greatest damage to buildings? A. P waves, which have the greatest amplitude B. S waves, which have the greatest amplitude C. body waves, which arrive before surface waves D. surface waves, which arrive after body waves
D. surface waves, which arrive after body waves
Which earthquakes cause the most damage: those at shallow depths, intermediate depths, or great depths?
Damage happens at the surface, so it has nothing to do with depth. It occurs where the buildings are poorly built.
What is a lateral moraine?
Dark bands of rock debris on the glacier surface that mark the boundaries between adjacent glaciers
Observations
Data Direct measurements (numbers) Indirect measurements (predictions based on past) Facts Can test hypothesis / prove an idea
Paleolongitude
Declination of the angle
Ductile Deformation
Deeper Hot Like playdough Flowing/bending
Geothermal Gradient
Deeper in the crust, hotter it is Highest change in temperature in the first 100km then increases at more constant rate
Isaac Newton
Defined the laws of motion and gravity. Tried to explain motion of the universe. Theory of Gravity.
How is Earth made up, density wise?
Denser materials toward the center
Pulling Force
Describes the tendency of oceanic crust to sink below the continental crust into the mantle at a subduction zone due to getting colder and denser Happens over millions of years, slowly
GPS
Designed for tank navigation Accurate to millimeters
Water on Mars
Detected using radar waves
Global Positioning System
Detects small movements of the Earth's surface. Accurate within a few millimeters.
Ptolemy (100-170 CE)
Developed equations to explain the paths
Foucault Pendulum
Device that first proved that Earth rotates on its axis. Swings back and forth on same plane
Copernicus
Devised a model of the universe with the Sun at the center, and not earth.
Oxygen
Didn't exist until ~2 GA, due to the development of photosynthetic organisms
Andesite
Diorite Result of subduction Igneous rock Volcanic Evidence of past ocean (himalayas) Medium Silica content
he shape of Earth's magnetic field is approximately that of a ____________. (Bar magnet)
Dipole
Which type of metamorphism affects the greatest volumes of rock?
Dynamothermal morphism
Africa
E Africa being rifted currently
Earth's Heat:
Earth got hit by a bunch of meteorites - the kinetic energy of the impact was transformed into heat energy. Radioactive Decay continuously adds heat.
What is the idea of catastrophism?
Earth has been affected by a series of catastrophic events such as the biblical flood.
How do we know Earth rotates
Earth spins rapidly on axis of rotation
Earth's surface is protected from solar wind and cosmic radiation by ____________.
Earth's Magnetic Field
Movements of Plates cause by Plate Tectonics
Earthquakes Volcanism Mountain Building
When would you expect an earthquake to occur in Ohio?
Earthquakes occur anywhere when local rock strain builds up, bend, and finally break.
Sedimentary deposition is a continuous process; rivers, lakes, and the ocean deposit sediments nonstop at a fairly constant rate. (T or F)
False
Magnetic Stripes
Effect of polar reversal, shows magnetism switching through midocean ridge crust generation
Solar winds
Electrically charged particles that stream from the sun's corona and are usually blocked by the Earth's atmosphere and magnetic field.
Visible light
Electromagnetic radiation that can be seen with the unaided eye
Earthquake (energy)
Energy transmitted as seismic waves that pass through Earth
Charles Darwin
English natural scientist who formulated a theory of evolution by natural selection (1809-1882). Theory for the formation of coral atolls.
Measuring Earth
Eratosthenes calculated circumference ~200 BC, measured shadows in two locations 800 km apart
The Earth was first estimated to be a sphere with a radius of approximately 7000 km by ______________.
Eratosthenes in 200 BC
The Earth System is a closed or open system?
Essentially a closed system; on balance, no net gain or loss of mass or energy.
Mineral Forms
Euhedral, Anhedral, Subhedral
What factors increases salinity ?
Evaporation Freezing of sea ice
How is polarity reversal mapped?
Examining the oceanic crust's mid-ocean ridge spreading.
Isostatic equilibrium
Exists when the buoyancy force pushing the lithosphere up equals the gravitational force pulling the lithosphere down.
A single mineral may take on multiple crystalline lattice structures. (T or F)
False
All minerals are held together by ionic bonds. (T or F)
False
All rock produced at the mid-ocean ridges consists of basalt (T or F)
False
Metamorphism brings changes in mineral arrangement and the texture of rocks, but it never leads to new mineral assemblages. (true or false)
False
Movement along faults often produces sharply angled rock fragments termed ____________
Fault Breccia
Surface expressions
Fault trace, fault scarp. (some faults have no surface expression)
Which type of magma is produced at the coolest temperatures?
Felsic
Outer Core and Magnetic Field
Flow in the outer core generates the magnetic field
Anticline
Folded rock like a rainbow Upward fold Ductile Deformation
Fold-Thrust belt
Folding of crust causing thrust faults in a continent-continent collision zone
What is an end moraine?
Formed at a stationary terminus as debris accumulates in front of the terminus
Igneous Rock
Formed by the cooling and solidifcation of maga Cooling/solid magma Earth mostly composed of this kind of rock
Limestone
Fossiliferous: identifiable shells and fragments. Chalk: consists of carbonate plankton shells
What is an example of uniformity?
Fossils of mud cracks compared to present day mud cracks.
simple proof of Earth's rotation
Foucalt's Pendulum
Fault
Fracture in a volume of rock, resulting in a displacement. Can be active or nonactive
Shocked quartz
Fractures in quartz, only form in response to extremely high pressures metamorphism, found in KT boundary clays, likely formed by meteorite force of impact.
GA
G is billion, A is ago
Beneath a blanket of sediments, oceanic crust is primarily composed of two rocks, ___________
Gabbro and Basalt
Expanding Universe Theory
Galaxy moving away at great speed
All portions of the mid-ocean ridge system have a well-defined axial trough (central rift).
false
Which plant genus dominated glaciated regions during the late Paleozoic and early Mesozoic?
Glossopteris
What did continents look like in the past?
Gondwana and Pangaea
Define isostasy:
Governs the rise or fall of the crust until the mass is buoyantly balanced.
A silica-rich igneous rock which has coarse crystals and which makes up much of the continental crust is ____________.
Granite
Why do continental crusts always collide?
Granite never sub-ducts because it is less dense than the mantle.
Galaxies
Gravity binds stars to galaxies
Ore minerals, such as galena and hematite, tend to be distinct in their very ____________
Great specific gravity
As compared to ultramafic rocks, mafic rocks have a _________
Greater Proportion of Silica
Eratosthenes
Greek mathematician and astronomer who estimated the circumference of the earth and the distances to the moon and sun (276-194 BC)
Striations
Grooves in rock that shows where glaciers have moved
Volcanoes which have submerged beneath the surface of the sea are termed ________
Guyots
With regard to minerals, ________ refers to ability to resist being scratched by other substances
Hardness
Dr. Peter Ward
Has investigated the K-T boundary layer around the world. He has found iridium, shocked quartz, and tektites.
Evidence of sea floor spreading
Heat flow, earthquakes, and volcanoes.
Metamorphic Rocks
Heating -> recrystallization High temp and pressure leads to higher grade metamorphism (low to high grade) High grade metamorphism - continent-continent collision, high temp Contact metamorphism can happen when sedimentary rock is interrupted by magma and heats the sedimentary, metamorphasizing it
Is saltier water lighter or heavier?
Heavier
The region of space that contains the material of our solar system is termed the
Heliosphere
Rhyolite (Granite)
High silica content (70-75%). Light colored.
Volcano type by heat
Hotter Less Silica Basalt Shield Volcanoes Less viscocity, runs fast, low shallow volcano Fluid like lava Hot spots/midocean ridge/divergent boundaries Nonviolent Colder More Silica Andesite-Rhyolite Stratavolcanoes/Composite volcanoes Steep High viscosity, sticky, piles on top of itself Subduction Zones Violent Alternating lava/pyroclast
Cleavage
How crystals break, tendency to break along planes of weakness
Convection
How earth vents heat Thermal expansion of hot rock lowers the density and causes it to rise -> eruption -> cools and gets dense -> sinks bc of gravity Can happen in gas, liquid, or ductile solids 1% expansion in volume leads to 1% decrease in density and requires 300-400 deg C increase Heat moves upwards in the form of hot, relatively less dense rock through the mantle to the crust, and comes back down when cold and relatively more dense. plate movement caused by this heat
Earthquakes
Hypocenter is the focus/center
Which transport medium carries the largest particles?
Ice
Comet core
Ice and debris.
Orthodox vs New ideas
Idea that pre 20th century, continents dont move Then in 1912, contintental drift (plowing through oceans) Then 70s Plate Tectonics
Metamorphic Rock
Igneous or sedimentary rocks transformed by high pressure and/or temperature
How do glaciers flow?
In a downslope direction from the zone of accumulation to the zone of ablation.
How do glaciers retreat?
In an accelerated fashion
Subduction zone
In tectonic plates, the site at which an oceanic plate is sliding under a continental plate.
What happens downstream?
In the zone of ablation, the ice melts
What happens upstream?
In the zone of accumulation, ice is created from snow
What does a planet with many craters indicatE?
Inactive volcanism, not as hot No evidence of tectonic plates
Catastrophism
Incorrect earlier view Catastrophes, noahs flood, shape the earth Big flood impossible, no evidence of it, Not enough water
Red shift
Increase in the wavelength of electromagnetic waves emitted by a star or galaxy due to its motion away from us. The faster the speed of the star or galaxy, the greater the red-shift.
The velocities of seismic waves traveling from earthquake foci ____________ with depth, occasionally making jumps known as ______________
Increase, seismicvelocity discontinuities
What is seismometer physics based on?
Inertia (resistance to change in position)
What are the physics of seismology?
Inertia, induction, and verde's laws
Coastlines receding are caused by:
Inflation or deflation of mid-ocean ridge Glaciation or deglaciation traps
The densest layer of Earth is the ___________
Inner core
Measuring Earthquakes
Intensity and magnitude
Magma
Interior molten rock
How are amounts and sizes of earthquakes related?
Inversely related by multiples of 10
By mass, the four most abundant elements in the Earth are oxygen, silicon, magnesium, and __________
Iron
The core
Iron rich sphere with radius of 3,471 Km
What is the core made up of?
Iron, nickel, and other heavy elements.
How does the lithosphere float on the asthenosphere?
Isostasy keeps the less dense lithosphere on top.
What happens to P Wave velocity at the core mantle boundary?
It decreases sharply
How has the Earth changed in earthquake risk?
It hasn't changed because that is impossible. There is a shifting in the map, but the risk has not changed.
What is the thermohaline circulation "conveyor belt" consist of? How long does it take?
It involves all major oceans and takes about 1000 years for water to complete this cycle
Why is the oceanic lithosphere rock younger than 70 million years old?
It takes 70 million years for mid-oceanic basalt rock to cool back down to the mantle.
Galileo
Italian astronomer and mathematician who was the first to use a telescope to study the stars
Caldera
Large depression with steep walls and flat floor, caused by volcano collapsing Volcano collapses from loss of support due to big eruption Big crater with volcano in middle Big drained magma crater below it
Planet
Large solid body orbiting a star (sun), nearly spherical
Rock Magnetization
Lava cannot have permanent magnetization. Iron bearing minerals will be magnetic. Dipoles align with Earth's magnetic field causing this.
First generation stars
Left a legacy of heavier elements. They are the oldest known stars.
What does a planet with many mountains indicate?
Less active volcanism Not as hot
Formation of Earth's atmosphere
Less dense gas molecules, such as hydrogen and helium rose to the surface. The sun heated the gases enough so that they escaped Earth's gravity.
Is warmer water lighter or heavier?
Lighter
Compaction and cementation of grains occurs during ____________
Lithification
The Earth System includes the:
Lithosphere, atmosphere, hydrosphere, and biosphere
What are observations?
Measurements or the results of experiments, they are the test of a hypothesis and help prove a scientific idea. Considered un-changeable and facts.
Observation:
Measurements that are considered unchangeable and are facts
How do you tell the thickness of ocean vs continental plates? Structure? Composition
Measuring the time it takes for earthquakes to travel through different materials/places
What is the mantle made up of?
Medium density elements.
Fractionation by partial melting
Melt separates from solid material during melting... enriches a melt with rocks having a higher melting temperature
Intensity
Mercalli Scale (falling of masonry structures, bridges collapsing, dishes and windows would shatter)
How did earth get hot originally
Meteorite impacts kinect energy = heat
Magnetic Stripes
Mid-Atlantic ridge
What is Earth made of?
Mineral, glasses, rocks, melts., volatiles, organic compounds
Lowest Boundary
Mohorovicic (Moho)
hardness is compared on the
Mohs Hardness Scale
French Academy of Science (1700's)
More in-depth studies of the earth's shape
17th Century thinking
Most scientists thought that the earth was hollow
Geologic Time
Mostly relative Earth is 4.5 billion years old
Magma Composition
Mostly silica by weight Then volatile dissolved gasses (H2O, Co2, sulfur, etc Lava, pyroclasts, gas erupted
Rocks in Colorado
Mountains - granite Volcanism - some volcanic rock
In 79 C.E., the citizens of Pompeii in the Roman Empire were buried by pyroclastic debris derived from an eruption of ____________.
Mt. Vesuvius
Earth Sciences:
Much broader than geology, includes climate, water, carbon, resources, and so on
Which of the following was NOT among the evidence for sea floor spreading?
NOT high heat flow at mid ocean ridges
What is the idea of uniformity?
Natural laws are permanent, so what happens today could have happened in the past.
Uniformity/Uniformitarianism
Natural laws existing today probably existed in the past Only partial info available, can only observe current stuff, some stuff takes too long to observe
Greenhouse effect
Natural situation in which heat is retained in Earth's atmosphere by carbon dioxide, methane, water vapor, and other gases.
Mineral
Naturally occuring, solid, ordered atomic arrangement, inorganic, (coal is not a mineral), formed geologically, definite chemical composition. Doesn't include minerals in the nutritional sense.
To be a mineral
Naturally occurring, inorganic. Definite chemical composition (molecular formula). Ordered atomic structure.
Andromeda
Next galaxy (2,200,000 light years away)
Earthquake epicenter
Place on the surface directly above where the earthquake takes place: Directly above the focus. Most earthquakes occur at plate boundaries.
Differentiation of Earth
Planetesimals clump into a lumpy protoplanet, The interior heats, softens, & forms a sphere, The interior differentiates into a central Nickel-Iron core, a stony outer shell-a mantle.
Global Plate Boundaries
Plate boundaries correlate with topographic and bathymetric features of Earth.
What kind of earthquakes are at transform faults?
Plates slide past each other, shallow depths, no volcanic activity
Intrusive Igneous Rock
Plutonic On the inside, remainds underground
Triple junction
Point where three plate boundaries intersect
Polarity Reversal
Polarity flips, causing a change in the orientation of iron in basalt over time as new rock is produced in midocean ridges Happens over millions of years Liquid iron core around solid iron induces Earth's magnetic field
Hyposometic Curve
Position due to the differing buoyancy of each type of crust (crust effectively floats on mantle)
Why are there almost no run-up events along the coasts of eastern South America and western Africa?
Probably because the earthquakes in the southern Atlantic ocean are not sufficiently large to produce observable tsunamis or tsunami-related deposits.
What are Seismic waved used for?
Probe the interior. Wave velocity changes with density. Echoes off layer boundaries bound back to the surface. Velocity changes and gives depth of layer changes.
Plate Tectonics
Process by which fragments (plates) of lithosphere move horizontally across the Earth's surface Heat escapes via convection, causes plate movement
Convection
Process by which, in a fluid being heated, the warmer part of the mass will rise and the cooler portions will sink. Occurs in the atmosphere and oceans due to temperature changes. Deep within Earth.
Faulting
Process of cracking that occurs when the folded land cannot be bent any further.
Comet tail
Produced when a comet's orbit brings it close to the sun and the dust and ice heat up. Always points away from the sun.
Age of ocean crust
Progressively older in both directions away from ridge
Alfred Wegener
Proposed the continental drift theory in the 1900s
Arthur Holmes
Proposed the existence of a mechanism for movement, mantle convection.
Harry Hess
Proposed the theory of sea-floor spreading.
Rifting
Pulling two continental plates apart No crustal root Topographic relief (local drop in elevation) Can create ocean crust/oceans
Planetesimal
Space object built of solid particles that can form planets through collisions and mergers. Clump into a lump of protoplanet.
Moho
Separates crust from the upper mantle, Deeper under near continents than oceans
A fine-grained clastic rock that splits into thin sheets is ____________
Shale
Where do earthquakes happen in mid-ocean ridges?
Shallow water in only the first 10 km beneath the seafloor.
Brittle deformation
Shattering, shallow crust Fracture Faults
How do oceans lose salt?
Shell forming marine organisms Basalt rock reactions Salts deposited with sediments on bottom of seafloor
Biochemical Sedimentary rocks
Shells, coral, cemeneted Limestone
Geologic Evidence of Shallow Seas
Shells/ocean fossils found in areas with no current water (himalayas, ohio) Shale (oil) Limestone (coral) Wear ptterns indicating water
What are the three primary forms of subaerial volcanoes?
Shield volcanoes, cinder cones, stratovolcanoes
Was damage extensive or small for the Virginia earthquake?
Small damage No deaths and minor injuries
Tektites
Small pherules or blobs of glass formed by meteorite impacts, which melt quartz and eject it into the atmosphere. Volcanoes are also a source.
Clastic Sedimentary Rock
Solid fragments and grains of pre-existing rocks/shells cemented together Formed by weathering/erosion, transported by wind/water to location of deposition Large pieces close to source (boulders), smallest gets furthest (maybe ocean, particles) Rivers sort sediment Sediment cemented by silicates/calcium and made into rocks Shale / sandstone
inner core
Solid iron and nickel alloy, youngest major structure, "Froze" 1-2 GA, Radius = 1220 Km, Density = 13g/cm^3
Crystal Growth
Solidification from melt, precipitation from solution, solid state diffusion
Data from Oceans
Sonar, magnetism, radiometric dating, fossil data, and heat flow was used to support Hess's Theory of Seafloor Spreading.
Doppler Effect
Sound waves compressed or stretched with relative motion
What is the Continuity Equation?
The amount of water present is equal to the amount flowing in minus the amount flowing out.
Wadati-Benioff zone
The band of earthquakes that line the descending plate.
Transform boundary
The boundary between tectonic plates that are sliding past each other horizontally.
Divergent boundary
The boundary between two tectonic plates that are moving away from each other. Continental lithosphere rifts apart and if spreading continues an ocean basin is formed. Seafloor Spreading forms ocean basins at divergent boundaries.
Nucleosynthesis
The cosmic formation of atoms more complex than the hydrogen atom.
Isostasy
The equilibrium between continental crust and the denser mantle below it. Plates "float" at an elevation depending on their depending on their thickness and and density.
What is the horn of the glacier?
The formed top part
Continental drift
The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations.
Describe the inner and outer core:
The inner core is solid from all of the pressure, forcing the atoms to stick together. The outer core is molten and liquid.
Paleolatitude
The latitude of a place at some time in the past, measured relative to the earth's magnetic poles in the same period. Differences between this and the present latitude are caused by continental drift and movement of the earth's magnetic poles.
Mountain + Lava =
Volcano -Steep - Stratovolcano/Composite - Subduction - Andesite -Shallow - Hot spot/midocean ridge - Basalt -
Mantle
The layer of hot, solid material between Earth's crust and core. Composed of igneous rock peridotite. "Transition zone". We also see flow within the mantle.
Why is there a shadow zone?
The liquid outer code blocks the S waves and slows down the P waves
Why do earthquakes happen in shallow areas of mid-ocean ridges.
The mantle is too hot for them to occur below 10 km.
Coriolis effect
The movement of objects like the wind and ocean currents to the right in the nortern hemisphere and to the left in the southern hemisphere as a result of earths rotation.
Terrestrial planets
The name given to the four inner planets: Mercury, Venus, Earth, and Mars
When two oceanic plates collide, which one sub-ducts?
The older and colder plate sub-ducts.
Describe the Lithosphere:
The outer 100 km of the solid Earth, where rocks are harder and more rigid than those in the plastic asthenosphere.
Gas giant planets
The outer solar system planets: Jupiter, Saturn, Uranus, and Neptune, composed mostly of hydrogen, helium, and methane.
12 major plates
The plate boundaries are not at coastlines. Most plates consist of both continental lithosphere and oceanic lithosphere.
What is the epicenter?
The point on the surface right above the rupture of the earthquake.
Continental crust
The portion of the earth's crust that primarily contains granite, is less dense than oceanic crust, and is 20-50 km thick.
Seafloor spreading
The process that creates new sea floor as plates move away from each other at the mid-ocean ridges.
What is a shear wave?
They are slower and reach a seismometer after compressional waves. They are secondary waves and deform materials by change of shape.
Magnetosphere
The region of Earth's magnetic field shaped by the solar wind.
Describe the Asthenosphere:
The region of the mantle where rocks become ductile, have little strength, and are easily deformed
Asteroid belt
The region of the solar system between the orbits of Mars and Jupiter, where many asteroids are found.
Geology:
The scientific study of the Earth
Cosmology
The scientific study of the universe
How do shorelines change after earthquakes?
The shoreline used to be different, but elasticity changed it when earthquakes happened.
Compressed waves
The shorter the wavelength, the higher the frequency
Asthenosphere
The soft, plastic layer of the mantle beneath the lithosphere on which the tectonic plates move.
Historical Geology:
The study of geologic events that have occurred in the past
What is stratigraphy?
The study of rock layers and horizontal layering.
Paleomagnetic
The study of the record of the Earth's magnetic field in rocks, sediment, or archeological materials.
Geosynclinal theory
The theory that Earth was shrinking or that huge basin filled with sediments were some how deformed and folded to form mountains.
Expanding Universe Theory
The theory that the whole Universe must be expanding because galaxies in every direction seem to be moving away from us.
How fast to S waves move?
They can only travel through solid matter (crust). 3.5 km/s at the crust 5 km/s at the uppermost mantle
Inclination
The tilt of a magnetic needle.
What is a problem for scientists when working out the geologic history?
The time scale for many processes is too long to observe.
What is radioactivity?
The transformation of an element into another isotope of the same element or another element
Cretaceous-Tertiary boundary (K-T boundary)
The transition from the Cretaceous period to the Tertiary, 65 million years ago. A major faunal shift due to extinctions, including the dinosaurs, likely due to an asteroid impact at that time.
Buoyancy
The upward force acting on an object (like an iceberg) floating or immersed in a fluid.
Fracture
The way a mineral looks when it breaks apart in an irregular way
Proto-Earth
The young, early developing Earth. Planetesimal grow into the proto-earth. The interior heats up and becomes soft and molten. Gravity reshapes proto-earth.
In the distribution of end moraines in Ohio which is the oldest and which is the youngest?
The youngest is at the top and the oldest is at the bottom
What is the idea of stratigraphy?
The youngest rock is at the top and the oldest is at the bottom.
Why does the glacier retreat uphill?
The zone of ablation is greater than the zone of accumulation. There is more melting than there is freezing.
What is a condition for mantle convection?
Thermal expansion of hot rock.
How are plate tectonics like a heat engine?
They allow heat from the core to escape outside of the surface.
The first stars
They formed in areas with lots of matter. It needed to be hot enough for fusion to occur. Larger stars created heavier elements through fusion. Stars created all elements. Sun is 2nd generation b/c it has heavier elements in it. Supernova = star exploding.
How do continents keep from sinking?
They have a lower density than that of the water around them.
Convergent Margin/Subduction Zone
Two plates move toward each other and one sinks beneath the other. For oceanic crust, the older lithosphere sinks beneath the edge of an adjacent plate. Same as subduction zone
A paleomagnetic record from one location shows increasing inclination with time. This indicates __________.
This is not enough information for determining how the magnetic pole has moved.
How big were previous earthquakes in Virginia and how big was that one compared to historic earthquakes?
This was big compared to previous earthquakes
Short period comets
Thought to originate in the Kuiper Belt, or associated scattered discs, which lie beyond the orbit of Neptune.
Thrust fault
Top goes up, but shallow angle Pushing together
How do we study crystal lattice?
Transmission electron microscope (TEM)
Laterite soils are most commonly found in which type of environments?
Tropical Rain forests
All minerals are chemical compounds (composed of more than one element). (T or F)
True
Two distinct minerals may have the same chemical formula. (T or F)
True
Convergent Margin / Collision Zone
Two colliding continental plates create a mountain range.
Van Allen Belts
Two doughnut-shaped regions 1,000-25,000 kilometers above Earth that contain electrons and protons traveling at high speed.
Transform Margin
Two plates abrasively grind and slide past each other. Strike-slip zone shallow, shear fault deeper Most occur in oceanic plates Strike slip earthquakes, shallow Rare volcanoes Rocks of different ages sliding past each other new rock sometimes created in middle
What kind of earthquakes are at rift zones?
Two plates move away from each other, they are mid-ocean ridges, shallow, and there can be volcanism
Convergent Margin / Subduction Zone
Two plates move toward each other and one sinks beneath the other. For oceanic crust, the older lithosphere sinks beneath the edge of an adjacent plate.
Transform Fault Margin
Two plates slide past each other, grinding and abrading their edges.
Subduction Zone
Type of tectonic plate boundary in which an oceanic plate/crust is subducted beneath the contiental crust bc they are being pushed together and the oceanic crust is denser and colder over time. Causes volcanoes on the continental part of the boundaries Passive margins can become subduction zone Sinking called "Pulling Force" Cold brittle subducting crust is prone to deep, high magnitude earthquakes up to 700km deep, - brittle deformation faults caused by stress Underthrusting
Physical Geology:
Understanding the processes active at or below the Earth's surface and the materials on which these processes act
Problems with Mantle Convection Mechanism
Unfortunately, mantle convection as a direct cause of plate motion just doesn't work. There are convection currents within the mantle and asthenosphere, but they don't appear to directly drive plate motion. These convection currents do act to transfer huge amounts of heat from Earth's core and heat generated by the decay of radioactive elements within Earth, but the conveyor belt model seems to have failed.
Big Bang
Universe expanded at a single point. Exploded ~13.4 GA
What are surface waves?
Vibrations that are trapped near the Earth's surface.
Seismic waves
Vibrations that travel through Earth carrying the energy released during an earthquake. Velocity depends on the properties of the materials the waves pass through. Paths curve because of REFRACTION of waves at density interfaces (density generally increases with depth) -Denser rocks = faster waves. -Less dense rocks = slower waves.
Erupted Materials:
Volatiles (steam, carbon dioxide, sulfur, nitrogen, other elements), Pyroclasts (solid material in a variety of sizes), lava
Extrusive Igneous Rocks
Volcanic rock on the outside, Earth's surface
What is discharge?
Water flow (Q) Depth x Width x Velocity
What makes water different than other elements.
Water loses density when solid and expands.
Oceans
When Earth becomes cool moisture condenses and accumulates eventually forming oceans.
Formation of Cross Beds
When blowing sand builds into sand dunes in a desert, the sand tumbles up the windward side of the dune, and settles in quieter air on the leeward side.
Archimedes Principle of Buoyancy
When body is immersed in fluid at rest, experiences an upward or buoyant force = fluid's weight displaced by body.
What is upwelling?
When deep waters are pushed upward
When are models changed?
When they do not match the observations.
What is downwelling?
When water from surface is drawn downward
What is the zone of accumulation?
Where the water flows in
What is the zone of ablation?
Where the water flows out
Where does refraction occur?
Where waves cross a boundary between rocks with different physical properties
The outer portion of a craton, where deformed rocks are covered by sediments, is termed the _________
platform
How do we study crystal lattice?
X-ray diffraction (XRD)
Which national park is home to a large volcanic caldera formed through a very large explosive eruption 640,000 years ago?
Yellowstone
Are we safe in Ohio from major earthquakes, say larger than a magnitude 6.0?
Yes
Can thermohaline circulation shut down?
Yes, if river discharge decreases salinity, water won't sink. (This may have happened during the last deglaciation, causing Europe to plunge back to an ice-age climate for a short period)
Did the Virginia earthquake occur in an area of previous seismicity?
Yes, the Central Virginia Seismic Zone
Rocks at ridge
Youngest rocks (at the ridge crest) have present-day (normal) magnetism. Stripes of rock parallel to the ridge crest alternate in magnetism (normal-reversed-normal, etc.).
Right-lateral and left-lateral are both examples of ____________ faults. a. strike-slip b. dip-slip c. oblique-slip
a
Comets
a celestial object consisting of a nucleus of ice and dust and, when near the sun, a "tail" of gas and dust particles pointing away from the sun. Come from Kuiper belt and the Oort Cloud beyond the solar system.
Regions where Precambrian metamorphic rocks are exposed at the surface are termed ____________.
shields
What may continents look like in the future?
all cluster back together to form supercontinent(s)
Basaltic lavas which solidify at the surface before flow ceases fracture irregularly, producing a sharp-surfaced lava rock named ____________
aa
Basaltic lavas which solidify at the surface before flow ceases fracture irregularly, producing a sharp-surfaced lava rock named ____________.
aa
With regard to minerals, hardness refers to ____________.
ability to resist being scratched by other substances
Earthquakes only occur ____________ the brittle/ductile transition depth.
above
The rate of motion of a lithospheric plate with respect to a stationary hot spot is termed ____________ plate velocity
absolute
Within the terminology of plate tectonics, an ______ is a continental coastline which coincides with a plate boundary.
active margin
where coast boundary and plate boundary meet
active margin
Earthquakes are most frequent near coastlines that are termed _________
active margins
Earthquakes are most frequent near coastlines that are termed ____________.
active margins
a type of melting, addition of water or carbon dioxide that cause rocks to melt at a much lower temperature
addition of volatiles
Currently, most geologists ____________.
agree that continental drift occurs; the mechanisms that drive drift are at work in the ocean basins and upper mantle and were unknown in Wegener's time
A continental volcanic arc occurs at ____________.
andes mountains
Coarse-grained diorite is most similar in mineral composition to fine-grained ____________
andesite
Coarse-grained diorite is most similar in mineral composition to fine-grained ____________.
andesite
The extrusive compositional equivalent of diorite is andesite .
andesite
type of lava flows that don't flow rapidly, higher SiO2 content makes this more viscious
andesitic
A fold shaped like an elongate arch is a(n) ____
anticline
Sediment
any unconsolidated (loose and unconnected) fragments of mineral grains, rock, or shell, or crystals precipitated from water
Coarse-grained gabbro is most similar in mineral composition to fine-grained ____________
basalt
The extrusive compositional equivalent of gabbro is basalt
basalt
type of lava flows that are thin and fluid
basalt
When in contact with hydrochloric acid, which mineral gives off bubbles of carbon dioxide gas?
calcite
Limestone reefs and salt deposits are important rocks in the reconstruction of Earth history because they ____________.
can be used to infer ancient climate
Limestone reefs and salt deposits are important rocks in the reconstruction of Earth history because they ____________.
can be used to infer the ancient climate of the Earth; they are deposited in environments that are restricted to warm climate
Organic Sedimentary Rocks
carbon-rich remains of once living organisms Coal
A neutral atom that loses an electron becomes a/an ______________ .
cation
what are rayleigh waves?
cause the ground to undulate in a rolling motion, like waves on the sea surface
what are love waves?
cause the ground to undulate laterally
Synthetically made glass and natural quartz crystals both exhibit ____________ fracture.
conchoidal
Synthetically made glass and natural quartz crystals both exhibit a fracture pattern termed ____________
conchoidal
Three types of heat transfer
conduction, convection, radiation.
smallest volcano
cone
As compared to the rocks that make up the crust, Earth as a whole is ____________.
considerably more dense
Organic (Sedimentary)
consist of carbon-rich relics of plants
Biochemical (Sedimentary)
consist of shells of organisms
The magnetic field of Earth in the geologic past has always stayed -------
constant
Basaltic lavas ____________.
contain more iron and magnesium than rhyolitic lavas
The two types of Earth's crust are _______________ and oceanic.
continental
these kind of plates don't subduct because they are too bouyant
continental
The lithosphere of Earth can be bent and broken, but will not flow because it is too __________
cool
All other factors being equal, intrusive rocks that form deep within Earth ____________ than intrusive rocks that cool near the surface.
cool more slowly
As compared to the asthenosphere, the lithosphere is ____________
cooler and less able to flow
As compared to the asthenosphere, the lithosphere is ____________.
cooler and less able to flow
Which earth layer has the greatest density?
core
Which layer has the greatest density?
core
Strong chemical bonds in which atoms share electrons are termed ______________ bonds.
covalent
Regions of continents that have not been subjected to orogeny during the past one billion years are termed ____________.
cratons
The lithosphere is composed of the ____________.
crust and the uppermost part of the mantle
The lithosphere is composed of the __________
crust and upper mantle
_____ and _____ are distinguished on chemical makeup
crust, mantle
rocks in which grains interlock with one another like pieces of a jigsaw puzzle
crystalline rocks
these form when mineral grains can grow unobstructed
crystals
The apparent polar-wander paths for continents that were not connected over some span of geologic history will likely ____________ concerning the positions of the ancient magnetic pole.
differ
an agent of metamorphism in which stress is greater in one orientation
differential stress
The angle between the direction that a compass needle points and a line of longitude at a given location is the magnetic __________________.
declination
a type of melting, base of the crust is hot enough to melt mantle rock
decompression
If the volatile content of magma is increased, its viscosity will ____________.
decrease
Continental crust rises higher because it is less _____________ than oceanic crust.
dense
As compared to continental crust, the rocks that make up oceanic crust are ________
denser
As compared to continental crust, the rocks that make up oceanic crust are ____________.
denser
The velocity of seismic waves changes with the ______________ of material.
density
Caliche is most commonly found in which type of environments?
deserts
A buried body of aragonitic limestone is recrystallized at low temperatures and pressures, producing calcite; this is an example of _______
diagenesis
physical and chemical alterations, including compaction and cementation, that occur as sediment is transformed into rock is known as
diagenesis
intrusive activity where magma intrudes into other rocks as planar, tabular bodies
dikes and sills
The shape of Earth's magnetic field is approximately that of a ________.
dipole (such as that produced by a bar magnet)
The apparent polar-wander paths for continents that were not connected over some span of geologic history will likely ____________ concerning the positions of the ancient magnetic pole.
disagree
Under the theory of plate tectonics, the plates themselves are ____________.
discrete pieces of lithosphere at the surface of the solid Earth that move with respect to one another
Light year
distance light travels in one year. (about 9.5 trillion km)
Iceland is one of the few places in the world that is both above sea level and situated atop a ____________ plate boundary.
divergent
Mid-ocean ridges are _______ plate boundaries
divergent
The lithosphere of the Earth is generally thinnest at and near ____________ plate boundaries.
divergent
plate boundary where two plates move apart from each other, mid ocean ridges
divergent
Mid-ocean ridges are ____________.
divergent plate boundaries
Natural glass is not considered a mineral because it ___________
does not have fixed crystalline structure
Natural glass is not considered a mineral because it ____________.
does not have fixed crystalline structure
A fold shaped like an upside-down bowl is a(n) ____
dome
The apparent polar wander path obtained from magnetite crystals in basalts on the North American continent is now interpreted to be the result of ____________.
drifting of the North American continent
A body of rock under high pressure is more likely to exhibit ____________ than is a body of rock at low pressure.
ductile
A hot body of rock is more likely to exhibit ____________ than is a cold body of rock.
ductile behavior
All lithospheric plates are approximately the same size and contain a combination of oceanic and continental crust. (t or f)
false
Nonviolent eruptions characterized by extensive flows of basaltic lava are termed ____________.
effusive
eruptions that produce lava flows
effusive
At a subduction zone, the overriding plate may be composed of ____________ lithosphere.
either oceanic or continental
Summed over the entire surface of Earth, rates of lithospheric production and consumption are ___________
equal
Differential stress will cause crystals to align in a preferred orientation unless the crystals are ___________
equant
Most sorting of detrital grains takes place during ____
erosion
The removal of detritus from weathered rock at an outcrop is termed _____
erosion
Geocentric
everything revolves around the earth
Pegmatites, which occur in dikes, are unusual among shallow intrusive rocks in that they possess __________ grains
exceptionally coarse
Phreatomagmatic eruptions are ____________.
explosive (pyroclastic)
eruptions that produce pyroclastic flows
explossive
igneous rocks that cool quickly at the surface
extrusive
silica rich minerals melt _____, silica poor minerals melt _____
first, last
On average, continental crust is approximately ____________ as thick as oceanic crust
five times
On average, continental crust is approximately ____________ as oceanic crust.
five times as thick
At continental rifts, vast bodies of basaltic lava flow forth from fissures, forming ____________.
flood basalts
the asthenosphere _____ when loaded
flows
Normal faults assume a more shallow dip angle with depth; when the fault plane becomes nearly horizontal, these faults are termed ___________
folds
Rocks resulting from thermal (contact) metamorphism will not possess ____________
foliation
Slaty cleavage, schistosity, and compositional banding are all examples of _____
foliation
Sedimentary rocks
formed by chemical precipitation of material from water at the Earth's surface, or by deposition and cementation of particles and debris transported by water, wind, or ice
Igneous rocks
formed by cooling and consolidation of magma
Chert
formed from quartz (silica) shells of plankton
Tetrahedron Structure
four large oxygen atoms at the corners, with a small silicon at the center
Minerals which do not possess cleavage are said to possess ___________
fracture
occurs for planes that lack planes of weakness
fracture
The diagram shows what type of silicate tetrahedral structure?
framework
In which type of silicate are the greatest proportion of oxygen atoms shared by pairs of adjacent tetrahedra?
framework silicates
Which type of silica has the greatest proportion of oxygen atoms shared by pairs of adjacent tetrahedra
framework silicates
Earth's hydrosphere consists of ____________
freshwater, the oceans, groundwater, and atmospheric water
Beneath a blanket of sediments, oceanic crust is primarily composed of two rocks, ____________.
gabbro and basalt
When the streak mark created by a mineral is a different color than the mineral, the streak is termed ______________ .
incongruent
The velocities of seismic waves traveling from earthquake foci ____________.
generally increase with depth, occasionally making abrupt jumps termed seismicvelocity discontinuities
the increase in temperature as depth of the Earth increases
geotherm
The rate at which the temperature of the Earth increases with depth is called the _________________ gradient.
geothermal
If the volatile content of magma is increased, its viscosity will _________
increase
a solid with disordered atoms
glass
Which plant genus dominated glaciated regions during the late Paleozoic and early Mesozoic?
glossopteris
Moving into interior of Earth, temperature and pressure both ____________
increase
Rapid, deep burial of sediments in an accretionary prism leads to the formation of a metamorphic rock termed ____________.
gneiss
Natural laws
govern natural events
Clastic sedimentary rocks are primarily classified on the basis of _________
grain size
Clastic rocks
grains are bonded by natural cement, mineral material that precipitates from water and fills the space between grains
Rapid chemical weathering tends to ____________ the rate of physical weathering in the same rock
increase
How do oceans contribute to land warmth?
gulf stream currents keep land warm
an extinct oceanic hot-spot volcano that has subsided below sea level
guyot
Goldilocks Zone
habitable zone able to sustain life (has the necessities for organisms to live, grow, and reproduce).
scratching resistance of a mineral
hardness
All basalts younger than 700,000 years old ____________.
have normal magnetic polarity
Wegener's idea of continental drift was rejected by American geologists because ____________.
he could not conceive of a valid mechanism that would cause continents to shift positions
Wegener's idea of continental drift was rejected by American geologists because ____________.
he could not give a valid explanation
a type of melting, rising magma carries mantle heat with it, this raises the temp in nearby crustal rock, which then melts
heat transfer
The region of space that contains the material of our solar system is termed the ____________.
heliosphere
lava with _____ viscosity will flow a shorter distance
high
higher levels of silica in lava leads to ______ viscosity
higher
higher silica content creates _____ viscosity
higher
continental plates float _____, oceanic plates float _____
higher, lower
Rapid physical weathering tends to ____________ the rate of chemical weathering in the same rock
increase
Hot spots are caused by ____________.
hot plumes of mantle material that rises up through cooler, denser surrounding rock
The Hawaiian island chain is an example of a(n) ___________
hot spot island chain
hot plumes of mantle material that rises up through cooler, denser surrounding rock
hot spots
volcanic plumes independent of tectonic plates
hot spots
Hawaii is an example of ____________ volcanism
hot-spot
Hawaii is an example of ____________.
hot-spot volcanism
Swelling of certain minerals due to incorporation of water into their crystal lattice is termed ____________.
hydration
The characteristic 'rotten egg' smell of many active volcanoes is derived from ____________.
hydrogen sulfide gas
The chemical reaction that transforms feldspar into clay is an example of ____________.
hydrolysis
Earth is mostly made up of this rock
igneous
rock that is formed from the cooling of magma
igneous
Thermal (contact) metamorphism occurs in areas surrounding ___________
igneous intrusions
Metamorphic rocks
igneous or sedimentary rocks that have been changed under high temperatures and/or high pressures
The lithification of material from a pyroclastic flow forms a rock called _______
ignimbrite
What is the general name for a rock formed from a pyroclastic flow deposit?
ignimbrite
if a body of magma becomes more felsic, its viscosity will ____________.
increase
At a subduction zone, the downgoing (subducting) plate ____________.
is always composed of oceanic lithosphere
sediments all become the same size as distance from the source ______
increases
A mineral within a metamorphic rock that can be used to provide a narrow constraint on the temperature and pressure of formation of the rock is termed a(n) ____________.
index mineral
As compared to the density of the asthenosphere, the oceanic lithosphere is ____________.
initially less dense at the age of formation, but eventually becomes more dense
In the picture above, the layer of the Earth labelled with a 4 is called the ____________ .
inner core
The densest layer of Earth is the ____________.
inner core
2 parts of the core
inner core and outer core
high grade or high metamorphic intensity
intense
Composite cones
intermediate in composition (andesitic), found at convergent plate boundaries. Composed of alternating lava and pyroclastic materials. Cone-shaped. Extremely hazardous (explosive eruptions).
Andesite (Diorite)
intermediate silica content (~60%). Usually gray, purple, or dark green.
When magma crystallizes, ____________ igneous rocks are formed
intrusive
igneous rocks that cool slowly underground
intrusive
By mass, the four most abundant elements in the Earth are oxygen, silicon, magnesium, and ______________.
iron
Describe the outer core
iron is molten and exists as a liquid
three most dominant elements beneath the surface
iron, oxygen, and silicon
Unlike the lithosphere, the asthenosphere ___________ over long periods of time
is able to flow
The Moho ____________
is found deeper underneath continents than under oceans
The Moho ____________.
is found deeper underneath continents than under oceans
Most terrestrial volcanic glass ____________.
is highly silicic in composition
If we mentally align the continents to fit Wegener's concept of Pangaea, evidence of Late Paleozoic glacial deposits ____________.
is much more readily explained than in the modern continental configuration
____________ commonly serves as a protolith in the formation of marble. a. Limestone
limestone
If the interior of the Earth was mostly liquid instead of solid, tides would be:
larger than they are
molten rock moving over ground
lava flows
With increasing altitude, the concentration of gases in our atmosphere becomes (less or more) dense
less
As compared to the density of the asthenosphere, the oceanic lithosphere is ____________.
less dense at formation but becomes more dense with age
For the majority of minerals, the streak color obtained when the mineral is scratched against a porcelain plate is _________ than the color in hand sample among crystals
less variable
thick continental crust is relatively _____, while thin ocean crust is relatively _____
light, heavy
Most commonly, felsic igneous rocks are ____________ in color when compared to mafic rocks.
lighter
The sides of a fold, where curvature is at a minimum, are termed ________
limbs
The difference between lava and magma is that ____________.
magma is found beneath the Earth's surface, whereas lava has reached the surface
measured magnetic field that oscillates perpendicular to mid ocean ridges, invoked to support sea floor spreading
magnetic anomalies
protects Earth's surface from harmful effects of solar wind
magnetic field
Marine magnetic anomalies result from sea-floor spreading in conjunction with ____________.
magnetic polarity reversals
Of the three primary chemical layers of the Earth (crust, mantle, core), which is the thickest layer?
mantle
Volcanoes that do not occur along either present or emergent plate boundaries are associated with ____________.
mantle hot spots
Olympus Mons, the largest known volcano in the Universe, is found on ___________.
mars
Density is the ratio of ___________ to volume.
mass
At a subduction zone, the overriding plate ____________.
may be composed of either oceanic or continental lithosphere
Fractionation
melt separated from solid material during melting
The New Age practice of surrounding one's self with crystals has a strong positive effect on ____________
mental health
What's the luster of galena, pyrite, silver, and gold? (one word)
metallic
igneous or sedimentary rock that has been changed under high temp or pressure
metamorphic
A buried body of shale is subjected to differential stress, causing clay minerals to realign and producing slate. This is an example of ________
metamorphism
Prerequisite condition for mantle convection
the thermal expansion of hot rock
Clay minerals within a buried body of slate are recrystallized at high temperatures and pressures to form mica, producing a rock called phyllite; this is an example of _________
metamorphism
Net chemical change in metamorphic rock induced by reaction with hot groundwater is termed ____________.
metasomatism
Very early in Earth's history, it was so hot that the surface was likely entirely molten.
true
Most of the pushing force driving plate motion is produced at __________
mid ocean ridges
Sea-floor spreading is driven by volcanic activity along _________
mid-ocean ridges
The single property that can be used to identify any mineral is ____________.
none of the above; multiple properties must be used to diagnose a mineral
The ______ is found deeper underneath continents than under oceans
moho
Magma
molten rock below the Earth's surface
if a body of magma is subjected to fractional crystallization, the resulting rock should be ____________.
more felsic than the magma
When rock is partially melted, the chemistry of the melt is ____________.
more felsic than the original chemistry of the rock that was partially melted
If a body of igneous (source) rock is subjected to partial melting, the magma that is produced is expected to be ____________.
more felsic than the source rock
At a divergent plate boundary, two opposed plates _______
move away from each other
At a divergent plate boundary, two opposed plates ____________.
move away from one another
What are body waves?
move in all directions- 3D Compressional motion (P waves) Shear motion (S waves)
At a convergent plate boundary, two opposed plates _____
move toward each other
At a convergent plate boundary, two opposed plates ____________.
move toward one another
Shear stress at sufficient depth within a fault plane can induce ductile shear, forming a fine- grained metamorphic rock named ____________
mylonite
Rocks
naturally formed aggregate of minerals and other solid materials such as glass and organic matter
Three things to be a mineral
naturally occurring definable chemical composition fixed crystalline structure
Alpha Centauri
nearest star outside our solar system and is a triple star
Presently, Earth's atmosphere is dominated by which two gases?
nitrogen and oxygen
the two dominant gases in the atmosphere
nitrogen and oxygen
Kimberlite Pipes
occurs in the Earth's crust in vertical structures, pipes. They are formed deep within the mantle, at between 150 and 450 kilometers depth, from anomalously enriched exotic mantle compositions, and are erupted rapidly and violently, often with considerable carbon dioxide and other volatile components. They deliver mantle rocks (xenoliths) and diamonds from throughout the crust to the surface where they can be studied.
Topographically, most of the ocean floor is made up of ____________.
ocean plains (2.5 to 4.5 km below sea level)
The pulling forces that produce the most rapid plate velocities are concentrated at ____________.
ocean trenches
At a subduction zone, the downgoing (subducting) plate is always composed of ____ lithosphere
oceanic
these kind of plates always subduct
oceanic
Tectonic plates might consist of ____________.
oceanic lithosphere, continental lithosphere, or both
In Bowen's discontinuous reaction series, the first mineral to crystallize from a mafic melt is ____________.
olivine
Minerals utilized by humans as a source of metal are termed ____________
ore minerals
In the picture above, the layer of the Earth labelled with a 3 is called the ____________ .
outer core
The rusting of iron and iron-rich minerals is an example of ____________
oxidation
The most abundant element in the Earth's crust is ______________.
oxygen
The silica tetrahedron that forms the backbone of all the silicate minerals is composed of silicon and what other element?
oxygen
where coast boundary does not meet plate boundary
passive margin
Broad, sediment-covered continental shelves are found along ________
passive margins
Continental coastlines that occur within the interior of a tectonic plate are called ____________.
passive margins
Faucault's Pendulum
pendulum sings back and fourth in the same place
Which rock composes the Earth's mantle?
peridotite
Edwin Hubble
person whom Hubble telescope is named after. he first classified galaxies by shape. Recognized the Doppler effect after a red-shift. Realized the galaxy is expanding.
the distinction between the lithosphere and asthenosphere is primarily on the basis of a difference in ____________.
physical rigidity
Frost wedging, root wedging, and salt wedging are all examples of __________
physical weathering
Bowen's continuous reaction series describes the crystallization behavior of a single mineral (with variable chemical composition), ____________
plagioclase
The silicate mineral that is found in the greatest variety of igneous rocks is ________
plagioclase
Two minerals with distinct atomic structures but the same chemical composition are termed___________ .
polymorphs
An igneous rock with a mixed texture of coarse grains (phenocrysts) surrounded by fine crystals (groundmass) is termed ____________.
porphyritic
Pegmatites, which occur in dikes, are unusual among shallow intrusive rocks in that they ____________.
possess exceptionally coarse grains
Deformed (bent, stretched, or cracked) lithosphere occurs ____________.
primarily on the margins of tectonic plates
Three types of earthquake waves
primary (p-wave), secondary (s-wave), surface wave.
The process of low-grade metamorphic rocks being altered to form high-grade metamorphic rocks is termed ____________ metamorphism
prograde
Chicxulub Crater
proposed meteorite impact crater, centered on chixiclub on the yucatan of mexico, discovered in 1950s at the time it was interpreted.
slab ____ force that drives plate motion
pull
ridge ____ force that drives plate motion
push
Volcanic bombs are ____________.
pyroclastic blocks that acquire aerodynamic shapes during flight out of the volcanic vent
Bombs, ash, and cinders are all examples of ____________.
pyroclastic debris
airborne volcanic fragments
pyroclastic debris
The greatest hazard to human life associated with volcanoes is __________
pyroclastic flows
Two common metamorphic rocks that typically lack foliation are ________
quartzite and marble
As compared to coarse-grained igneous rocks, all fine-grained igneous rocks cool and solidify more _______________
quickly
The process of high-grade metamorphic rocks being altered to form low-grade metamorphic rocks is termed ____________ metamorphism.
retrograde
In a ____________ fault, the fault plane is greater than 35° from horizontal and the hanging- wall block moves upward relative to the footwall bloc
reverse
what kind of faulting resulted from viriginia earthquake?
reverse
Compressional stress causes what kind of fault?
reverse and thrust
Whereas the crust-mantle boundary represents a change in rock type, the lithosphere-asthenosphere boundary is due to a change in the _____________ of the material.
rheology
Coarse-grained granite is most similar in mineral composition to fine-grained ____________.
rhyolite
type of lava flows with the highest SiO2 and is the most viscous lava, it rarely flows
rhyolitic
The mid-ocean ridges are elevated above the surrounding seafloor because ____________.
ridge rocks are hot and therefore of relatively low density
Chemical Sedimentary Rocks
rocks formed from minerals precipitated from a solution or left behind by evaporation
The difference between breccia and conglomerate is that conglomerate possesses more _________ grains than breccia
rounded
Geologically, medium-sized sediment refers to _________
sand
It is unusual for wind to carry grains larger than ____
sand
____________ commonly serves as a protolith in the formation of quartzite.
sandstone
clastic rock made of sand-sized particles
sandstone
What are some sedimentary rocks that form in some coastal environments?
sandstones, shales, limestones
The majority of the rocks that occur at the surface of Earth are ___________ rocks
sedimentary
rock that is formed from the chemical precipitation of material from water at the Earth's surface, or by the deposition and cementation of particles and debris transported by water, wind, or ice
sedimentary
____________ commonly serves as a protolith in the formation of slate. a. Limestone
shale
clastic rock made of clay-sized particles
shale
What type of rocks would you expect to find in the middle of a continent?
shallow marine rocks
Spreading peanut butter on bread is an application of --------stress
shear
The diagram shows what type of silicate tetrahedral structure?
sheet
largest type of volcano
shield
Olympus Mons, the largest known volcano in the Universe, is an example of a _____________.
shield volcano
Of the three primary forms of subaerial volcanoes, ____________ are the largest in area
shield volcanoes
Of the three primary forms of subaerial volcanoes, ____________ have the most gently sloping sides, due to the low viscosity of the basaltic lavas which form them.
shield volcanoes
most common mineral in the crust and most important rock-building material
silicate
Most minerals and rocks on Earth are classified as _____________ based on their elemenal composition.
silicates
most rocks on Earth made of these type of minerals
silicates
the cause of so much oxygen in the crust
silicates
Most terrestrial volcanic glass is highly __________ in composition
silicic
The four most common elements in the Earth as a whole are oxygen, __________ , magnesium, and iron.
silicon
a sheetlike intrusion that lies parallel to surrounding layers of sedimentary rock
sill
a type of tabular intrusion that parallels rock fabric
sill
As lithosphere cools to the sides of a mid-ocean ridge, it begins to _________
sink
____________ commonly serves as a protolith in the formation of phyllite.
slate
A polished surface produced by scraping of rock along a fault is termed a(n) ___________
slickenside
At a transform plate boundary, two opposed plates __________
slide past each other
At a transform plate boundary, two opposed plates ____________.
slide past one another
low grade or low metamorphic intensity
slight
An aurora is produced when ____________.
solar wind particles are directed toward the poles and excite atmospheric gases
the inner core is ______
solid
Clastic (Sedimentary)
solid fragments and grains cemented together
____________ is a mineral property defined by the density of the mineral sample divided by the density of water (1g/cm3).
specific gravity
____________ is a mineral property defined by the density of the mineral sample divided by the density of water (1g/cm3).
specific gravity
As seismic (earthquake-generated) waves travel downward and reach the Moho, they ___________
speed up
As seismic (earthquake-generated) waves travel downward and reach the Moho, they ____________.
speed up
Earth
spins rapidly on an axis of rotation
That the Earth is solid, rather than hollow, is a relatively new discovery, not widely accepted until the 17th century.
true
Earth's magnetic field is generated by ________
the flow of the liquid outer core
Earth's magnetic field is generated by ____________.
the flow of the liquid outer core
this generates the magnetic field
the flow of the outer core
mesosphere
the mantle between the bottom of the asthenosphere to the core-mantle boundary. temperature at the core-mantle boundary is about 5000C
lithosphere
the outer 100 km of the solid Earth, where rocks are harder and more rigid than those in the plastic asthenosphere.
what is the focus of the earthquake?
the point where earthquake starts to release the elastic strain of surrounding rock.
Oceanic crust
the portion of Earth's crust that is usually below the oceans and not associated with continental areas, thinner and higher in density that continental crust and basaltic rather than granitic in composition.
Every plate boundary can be recognized by ____________.
the presence of an earthquake belt
Nebular Theory
the theory that the solar and stellar systems were developed from a primeval nebula.
The oceanic lithosphere is _________ as you go further away from the mid ocean ridges
thicker
triple junction is a place on Earth's surface where ____________.
three lithospheric plates meet
A boundary at which two plates slide past each other is a _______________ boundary. (one word)
transform
Segments of the mid-ocean ridge system are offset. Between the offset segments we observe ____________.
transform
The San Andreas Fault Zone in southern California is an example of a ____________ plate boundary.
transform
plate boundary where plates slide past each other, usually occur between oceanic plates
transform
Segments of the mid-ocean ridge system are offset. Between the offset segments we observe ____________
transform faults
Segments of the mid-ocean ridge system are offset. Between the offset segments we observe ____________.
transform faults
Grains become rounded primarily during __________
transportation
Earth's geothermal gradient is the rate of temperature change incurred by ___________
traversing down earth's interior
Earth's geothermal gradient is the rate of temperature change incurred by ____________.
traversing down within Earth's interior
Most of the mass of the Earth's atmosphere is found within what atmospheric layer?
troposphere
In nature most examples of minerals do not grow as large, well-formed, euhedral crystals.
true
A volcano emits ash, which falls from the sky, settles in layers, and is eventually cemented. The resultant rock is termed ____________.
tuff
vapor and aerosols that exit a volcano
volcanic gases
intrusion formed within the magma chamber of volcano
volcanic neck
Ash, cinders, and blocks are all types of ____________.
volcanisclastic debris
Chemical weathering takes place most rapidly in environments that are ____________
warm and moist
in which climatewould you most likely find calcite in the topsoil?
warm, moist
Important volatiles in magmas include ___________
water and co2
Phreatomagmatic eruptions take place when ____________.
water enters the magma chamber and forms steam
Gases that are abundantly emitted by volcanoes include ____________.
water vapor co2 and sulfer dioxide