Geology 1010 For cedar valley
Who developed the theory of continental drift?
Alfred Wegener
Briefly describe how the fit of the continents, mountain ranges, past climates, past glaciation, and distribution of fossils support Wegener's idea of Continental Drift.
Alfred Wegener proposed that the continents were once united into a single supercontinent named Pangaea, meaning all earth in ancient Greek. He suggested that Pangaea broke up long ago and that the continents then moved to their current positions. He called his hypothesis continental drift.
Name that plate boundary: shallow ocean, middle of ocean, youngest seafloor, shallow earthquakes
Divergent
What colors are mafic and felsic?
Felsic- light Mafic-dark
Congrats! thats the end.
Go get yourself a treat.
How does apparent polar wandering, magnetic reversals, and seafloor spreading support plate tectonics?
Therefore, the concept of apparent polar wander is very useful in plate tectonics, since it can retrace the relative motion of continents, as well as the formation and break-up of supercontinents.
___________ are molten rock (lava or magma). Grains Melts Metals Minerals Volatiles
Melts
Are the following substances minerals? If not- Why not? Salt, Gold, Steel, Diamonds, Ice, Pearls, Coal, Brass, Copper, Sugar, Obsidian
Minerals -Salt -gold -Diamond -Ice -Copper Non Minerals -Steel -Brass -Sugar -Obsidion
As a rock melts, which mineral melt first? Which melts last? If you only partially melt the rock, is the magma more felsic or mafic than the original rock?
Quartz melts first will be less mafic olovine will melt last
Phanaritic
Rock consists of large crystals that are clearly visible to the eye with or without a hand lens or binocular microscope.
What is the earth made of?
Rocks Minerals Violates Melts Plants Glass Grain Cediment Metals
In March of 2011, a devastating earthquake and tsunami struck Japan. Explain the tectonic setting in detail that ultimately caused this earthquake.
SUBDUCTION The 2011 Tohoku earthquake struck offshore of Japan, along a subduction zone where two of Earth's tectonic plates collide.
Describe seafloor spreading. How does seafloor spreading account for the distribution of ages of the ocean crust?
Seafloor spreading occurs at divergent plate boundaries. As tectonic plates slowly move away from each other, heat from the mantle's convection currents makes the crust more plastic and less dense. The less-dense material rises, often forming a mountain or elevated area of the seafloor. Eventually, the crust cracks
Describe the differences between continental and oceanic crust. Which is older? Why?
The continental crust is older than the oceanic crust.Because continental crust is rarely destroyed and recycled in the process of subduction. Seafloor spreading!
Pegmatitic
Very large crystals formed by extremely slow cooling, or in the presence of water.
___________ are materials that can be transformed into a gas in the conditions of Earth's surface. Rocks Volatiles Grains Melts Metals
Volatiles
Identify the oceans and land continents
Will not let me put photo so look it up
What is a mineral?
a naturally occurring, inorganic solid that has a crystal structure and a definite chemical composition
sill
a slab of volcanic rock formed when magma squeezes between layers of rock
Which of the following does not describe continental crust? continental crust is less dense than oceanic crust continental crust is thicker than oceanic crust continental crust is older than oceanic crust continental crust is composed of granite continental crust is mafic
continental crust is mafic
What are the layers of the earth?
crust, mantle, outer core, inner core
glassy
crystal unable to form; Rapid rate of cooling prevents crystals from forming looks like glass!
What was the name of Wegener's supercontinent?
Pangea
What is partial melting?
Partial melting is the transformation of some fraction of the mass of a solid rock into a liquid as a result of decompression, heat input, or addition of a flux.
Phaneritic
Phaneritic: any coarse-grained igneous rock, often intrusive, usually formed as a result of a longer cooling history (ex. granite, gabbro)
What happens during Oceanic-Oceanic plate boundary?
Plates are moving towads each other Earthquakes- Deeper further away from the trench
continental-continental convergence
Plates moving towards each other Earthquakes- shallow happens where 2 continental plates collide and push up creating mountain ranges
What is a hot spot? How do they form? Name 2 examples.
A hot spot is an area on Earth over a mantle plume or an area under the rocky outer layer of Earth, called the crust, where magma is hotter than surrounding magma. The magma plume causes melting and thinning of the rocky crust and widespread volcanic activity. Hawaii Yellowstone iceland
Batholith
A mass of rock formed when a large body of magma cools inside the crust
Laccolith
A massive igneous body intruded between preexisting strata
Cleavage
A mineral's ability to split easily along flat surfaces.
Dike
A slab of volcanic rock formed when magma forces itself across rock layers
Name that plate boundary: shallow earthquakes, no volcanoes, high mountains, no ocean
Continental-Continental
What are 3 causes of melting and where does each occur?
Decompression Flux melting Heat induced
Felsic
Describes magma or igneous rock that is rich in feldspars and silica and that is generally light in color.
Be able to identify specific examples of each plate boundary. (Mid-Atlantic Ridge, Alps. San Andreas Fault, Aleutian Islands, Indonesia, Cascades, Andes, East Pacific Rise, Japan,Himalayas,)
Divergent -Midatlantic ridge -East pacific rise Oceanic-Oceanic Convergent -Indonesia -japan -Aleution island Oceanic-continental convergant -Andes -Cascades Coninental-continantal convergent -Himalays -alps Transform -San Andreas fault
What are the different kinds of earths crust?
Divergent Oceanic-Oceanic Oceanic-Continental Continental-Continental Transform
transform boundary
Earthquakes every depth NOT A PLATE BOUNDARY A plate boundary where two plates move past each other in opposite directions
About 300 million years ago, the Appalachian Mountains in North America were matched up with the identical rocks from which area(s)? Europe and Asia Antarctica South America Australia
Europe and Asia
What lines of evidence were added to develop Plate Tectonics?
Evidence from fossils, glaciers, and complementary coastlines helps reveal how the plates once fit together.
What minerals would you expect to find in the following rocks? -Granite -Rhyolite -Pegmatite -Gabbro -Basalt -Obsidian
Granite -biotite -quartz -feldspar -muscovite -amphibole Rhyolite -biotite -quartz -feldspar -muscovite -amphibole Pegmatite -biotite -quartz -feldspar -muscovite -amphibole Gabbro -olovine -pyroxene -amphoblie Basalt -pyroxene -feldspar -olovine amphobile Obsidian -NONE
Calculate the half and full spreading rates in cm/year for the Northern East Pacific Rise. The distance from one coast to the ridge is 1760 km. The age at this location is 20 Ma. (Keep in mind that there are 100,000 cm in 1 km. Ma = millions of years)
Half-Spreading Rate Answer:8.8 Full-Spreading Rate Answer:17.6
oceanic-continental convergence
Has a Wadiaff benioff zone. more dense oceanic plate dives under continental plate. forms a trench. causes volcanoes, and earthquakes (Andes Mountains)
Mafic
Igneous Rock containing large amounts of Iron and Magnesium, dark in color
Concordant coastline
In this type of coastline, the layers of rock are parallel to the direction of the coastline.
What does "intraplate" mean?
Intraplate pertains to processes within the plates
What is the tectonic setting of Utah?
Introplate
Just know these ones
Mafic Minerals (dark color)- Olivine, Pyroxene, Amphibole Felsic Minerals (light color)- Quartz, Feldspar, Muscovite (Biotite is dark in color but is in the middle of the felsic-mafic scale. It is found more often as black specs in felsic rocks.) Quartz- most common, scratches glass, durable Halite- table salt, cubic cleavage, salty taste Calcite- fizzes in acid, rhombohedral cleavage Magnetite- magnetic Olivine- olive green color, sometime has black specs Pyrite- Fools gold
The continents were once joined in a supercontinent named _______________. Panthalassa Indo-Asia Pangaea Eurasia
Pangaea
Intrusive or extrusive for thr minerals above?
Obsidian -Ex Ryolite -ex Basalt -Ex Granite -In Gabbro -in Pematite -in
Describe the igneous texture and composition for each of the igneous rocks listed above.
Obsidian -glassy Rhyolite - Aphinitic Basalt -Aphinitic Granite -phanaritic Gabbro -Phanaritic Pegmatite -Pegmatitic
Name that plate boundary: trench, wadati-benioff zone, volcanoes on a coastline
Oceanic- Continental
Name that plate boundary: trench, wadati-benioff zone, volcanoes, islands, ocean
Oceanic- oceanic
As a magma crystallizes, which mineral crystallizes first? Which crystallizes last? In fractional crystallization, does the magma before more felsic or more mafic as more and more minerals crystallize?
Olovine will crstalize first quartz is the last will be more Felsic
Which layer of the Earth is composed of a liquid? Outer core Lithosphere Mesosphere Inner core Asthenosphere
Outer core
Texture
The look and feel of a rock's surface, determined by the size, shape, and pattern of a rock's grains.
What happens during A divergent plate boundary?
The plates move away from one another, making a ridge in the middle. Seafloor spreading Earthquakes here-Shallow
Luster
The way a mineral reflects light
What is a hot spot?
a volcanically active area of Earth's surface far from a tectonic plate boundary
What is the hardness of a mineral?
ability to resist scratching
In terms of plate tectonics, where does magma form?
divergent boundaries (decompression melting), convergent boundaries (flux melting), and mantle plumes (decompression melting).
Aphinitic
fine grained, can not see the minerals or crystals
Earth is a layered sphere with the ________-density material found near the center of Earth and the ________-density material located near the surface. lowest; lowest highest; lowest lowest; highest highest; highest
highest; lowest
The ______________________ is the surface layer of the Earth. outer core asthenosphere mantle mesosphere lithosphere
lithosphere
The formula for density is d=mv where d = density, m = mass, and v = volume. Which of the following formulas correctly shows the formula rearranged to solve for mass? m=dv m=d−v m=dv m=vd
m=dv
The ______________ is composed of high amounts of iron and magnesium. core mantle crust
mantle
Decompression
melting due to a drop in confining pressure that occurs as rock rises
The seafloor magnetic pattern is best described as ________. (See Figure 2.16b on page 60) perpendicular to and symmetric about mid-ocean ridges parallel to and symmetric about mid-ocean ridges parallel to, but not symmetric about mid-ocean ridges perpendicular to, but not symmetric about mid-ocean ridges not related to the location of mid-ocean ridges
parallel to and symmetric about mid-ocean ridges
fractional crystallization
process in which different minerals crystallize from magma at different temperatures, removing elements from magma
specific gravity
ratio of a mineral's weight compared with the weight of an equal volume of water (the density of a mineral)
Compostion
the chemical makeup of a rock mafic, felsic
Streak
the color of a mineral's powder
crystal habit
the general shape of a crystal or cluster of crystals that grew unimpeded
When the Earth formed, differentiation occurred resulting in a core and mantle due to: volcanoes releasing volatiles which formed the atmosphere. the high density iron sinking to the core. meteorites striking the surface of the Earth. continuing meteorite impacts melting the Earth's crust.
the high density iron sinking to the core.