Geology Flash Cards
Body Waves and Surface waves
are fast, high frequency waves that travel through the interior of the earth —> Surface waves are slow, low frequency waves that travel at or near the earths surface.
Natural Mineral
formed by geologic or biologic process
o What did Yang and Song discover and publish this year?
§ Earth's inner core is slowing down
Mineral classes
§ Isolated --> Olivine § Single-chain--> Proxene § Double chain--> Amphibole § Sheet--> Muscovite § Framework --> Feldspar, and quartz
o Consequences of this?
§ Length of the day! § Magnetic field in outer core
What is a ternary diagram? How do we use it to understand differences between rocks?
A ternary diagram is a type of graph used to plot the relative proportions of three variables on a triangular diagram. It is used to understand the differences between rocks based on their chemical composition. The three axes of the graph represent three components of the rocks such as quartz, feldspar, and mafic. The data is then plotted on the graph, which allows for comparison of the various rocks and their compositions. The graph can also be used to identify certain types of rocks and to gain insight into how they were formed.
Granite:
Granite typically contains quartz, mica, and feldspar minerals. It may also contain hornblende, pyroxene, muscovite, magnetite, zircon, apatite, tourmaline, topaz, and garnet.
Solid Mineral
- non-liquid, non-gas (state is determined by T/P conditions) - can change state but only considered a mineral in solid state -Ice considered a mineral; water is not
Sublimation formation
1. The formation of a mineral directly from a gas. Usually requires super hot air that is abruptly cooled. Occurs at volcanic vents , geysers, and in deep space.
Precipitation formation:
1. The formation of a mineral directly from a solution of liquid H2O or CO2. Minerals will form when the solution is supersaturated with dissolved ions. This occurs at earths surface via evaporation (salt flats), Geysers or iin caves. Can also occur at hyprothermal vents on the ocean floor.
What is the hinge line fold?
A Hind line fold is a type of fold that is defined by a single axial surface and is symmetrical in the axial plane. It is characterised by a single hinge line and two limbs that dip in opposite directions. It is commonly found in metamorphic rocks that have undergone differential stress.
· What is a batholith?
A batholith is a large, irregularly shaped mass of intrusive igneous rock that is typically exposed at the surface after erosional processes have removed the overlying rocks. It is usually composed of granitic rocks and can be hundreds of kilometers in size.
Central Vent
A central vent is a type of volcanic vent that is located at the center of a volcanic crater or caldera. It is the main conduit through which magma and volcanic gases are expelled during volcanic eruptions.
Conduit
A conduit in geology is an underground passage or pipe through which groundwater, magma, or other fluids can travel. It is typically found in areas of volcanic activity, such as calderas, or near geological faults or fractures. Conduits can also form naturally from the process of erosion, in which water and other elements slowly wear away at rock and create a passageway.
Fault Scarp:
A fault scarp is a small step in the ground surface caused by the movement of rocks along a fault line. Fault scarps can be used to measure the displacement along a fault line, and can be used to identify the location of faults.
What is a geologic contact? How is it different from contour?
A geologic contact is the boundary between two different geologic units, such as between a layer of sedimentary rock and a layer of igneous rock. It is different from a contour in that a contour line is a line on a map that connects points of equal elevation, whereas a geologic contact is a physical boundary between different types of rock.
Hanging wall
A hanging wall fault is a type of fault where the hanging wall, or the side of the fault closer to the surface, is displaced upward relative to the footwall, or the side of the fault deeper in the ground. This type of fault is often found in areas with steep topography, such as mountains and hills.
Magma Chamber
A magma chamber is a large, underground reservoir of molten rock located beneath the Earth's surface. It is usually formed at the base of a volcano, and is the source of the magma that eventually erupts from the volcano. Magma chambers can also form from the melting of the Earth's crust due to the movement of tectonic plates.
What is a polymorph? What are two examples of polymorphs?
A polymorph is a type of solid material that has the same chemical composition, but different crystal structures. Two examples of polymorphs in geology are diamond and graphite, which are both variations of the same element, carbon. The nature of atomic bonds controls characteristics. Sheets are a weak form of crystal bonding. Frameworks are a very strong form of bonding. Two minerals with the same chemical composition but differeing crystal structures are polymorphs. EX: Diamond and graphite are bth natice element minerals made entirely of carbon.
· Who is Alfred Wegener?
Alfred Wegener and Continental Drift: German meteorolgist and polar explorer wrote the origins of the continent and oceans in 1915 Suggested the continents were once a massive supercontinent named Pangea. His theory was rejected in 1915 1. He was not a geologist 2. He was german and racisim excisted due to WWI 3. He lacked a convincing mechanism to explain how or wh the continens drifted across the ocean, did not have plate tectnonics
What is the axial plane fold?
An axial plane fold in geology is a fold in which the axial plane is parallel to the direction of the compressive forces or stresses that created it. It is typically composed of two or more layers of rock that have been pushed together, resulting in a change in the orientation of the original layers. The sides of the fold typically dip away from the axial plane, creating a curved structure.
Defined crystalline structure:
Arrangement of elements in a repreatable and translatable pattern.
What was present at Joshua Tree before the White Tank and how did that rock form?
Before the White Tank, Joshua Tree was home to large granite monoliths. These rocks were formed when magma cooled and solidified beneath the Earth's surface. Over time, erosion and weathering exposed the granite, which is now a popular site for rock climbing.
· What are the ways in which rock can be deformed?
Brittle deformation vs. Ductile deformation Shear zones are zones of intense ductile deformation that are thin relative their lateral extent. Shear zones, like faults, typically show offsets of older structures, but unlike faults, they lack through-going brittle fractures. In practice, faults and shear zones are closely related.
What are some of the physical properties we use to ID minerals?
Color, luster, Streak, Bowens temperature reaction series, rock composition, TEXTURE, Composition, Hardness.
Basalt
Common minerals found in basalt include plagioclase feldspar, pyroxene, olivine, amphibole, and magnetite. Other minerals that may be present in small amounts include quartz, ilmenite, apatite, and biotite.
What are some differences between the two in terms of composition and weathering rates?
Composition: Granite is made up of quartz, mica, and feldspar, while limestone is composed primarily of calcite. Weathering Rates: Granite is composed of harder minerals and is therefore more resistant to weathering than limestone. Limestone is composed of softer minerals, making it more susceptible to weathering and erosion. The weathering rates of granite and limestone will depend on the environment they are exposed to.
Dikes & Sills:
Dikes and sills are geological structures that form when molten rock rises in a vertical or horizontal direction and cools and solidifies. Dikes are steeply inclined intrusive rocks that form when magma rises along fractures and solidifies. Sills are tabular bodies of rock that form when magma is injected between existing layers of sedimentary rock and solidifies.
Who is Norman Bowen? What did he discover?
End purpose of what he did was that the silicate bonds determines the temperature which minerals were formed
Crystallization formation
Formation of a mineral directly from magma or lava. This formation can occur either at or below the earths surface. By for the most common type of mineral formation! The type of mineral that will form through this process is dependent on: organinal chemistry of melt, temperature of melt
Gabbro:
Gabbro is an igneous rock that is composed mainly of plagioclase feldspar and pyroxene minerals. Common minerals found in gabbro include olivine, hornblende, augite, biotite, magnetite, and labradorite.
Hotspots
Hotspots: are places where the mantle is unusually hot, generating melt that punches through the earths crust. Can etither create a flood like motion creating a flat Flood basin at the bottom of the ocean, or it can create pin point spots where volcanoes will form in the ocean, creating a chain as the crust moves across the mantle. (Hawaii)
· How can you ID this difference in hand sample?
In a hand sample, the coarser-grained intrusive rocks can be identified by the presence of large mineral grains that can be seen without magnification. The finer-grained extrusive rocks are much harder to distinguish without magnification, as the individual grains are too small to be seen.
What is the limbs of a fold?
In geology, a limb is a geologic feature that has a curved or bent shape, usually created by the action of folding forces that deform the strata. Limbs can be formed by a variety of deformation processes, including faulting, folding, and thrusting. Limbs can often be seen in the field, as outcrops of rock that show the curved shape of the limb.
· What is the textural consequence of this difference?
Intrusive igneous rocks have a coarse-grained texture, while extrusive igneous rocks have a fine-grained texture.
Silicate Classes
Isolated- 0bonds between oxygenes, Single Chain- 1 or 2 bonds, Double Chain - 3-4, Sheet -3, Framework- 4, Sheet - 3, Framework, 4——> relate this to bowens minerals where olivine is isolated. Look at the lab!!!!!
· What is jointing? Why does it happen?
Jointing in geology is the formation of cracks and fractures in rocks due to tectonic forces, weathering, and other causes. Jointing is caused by the stresses of tectonic forces in the Earth's crust which cause rocks to expand and contract. Weathering can also contribute to jointing, as it weakens the rock and allows for natural fractures to form. Jointing can also be caused by the cooling of molten rock, and by the movement of glaciers.
Magnetization patterns:
Layers of volcanic rock record magnetic changes over time. When measured, these iron minerals indicate movement of earths dipole. This suggests the earths magnetic dipole has not always pointed north —> this is called polar wander!!!!! But different rocks had a different wander, this was due to the movement of the continents.
What is mafic versus felsic magma? How does this difference affect volcano explosivity?
Mafic magma is a type of magma that is rich in iron, magnesium, and calcium and is typically darker in color. It is denser and more viscous than felsic magma and is usually created from partial melting of the Earth's mantle. Felsic magma is a type of magma that is rich in silicon and aluminum and is typically lighter in color. It is less dense and less viscous than mafic magma and is usually created from partial melting of the Earth's crust. The difference between mafic and felsic magma affects volcano explosivity because mafic magma is denser and Less viscous and tends to contain more dissolved gases than felsic magma. This means that felsic magma is more likely to explode when it reaches the surface than mafic magma, which tends to be less explosive.
· Be able to explain how you can start with 1 magma (melted mantle) and end up with 2 distinct crust types
Mechanical Layers of the Earth: Solid inner core, liquid outer core, Ductile Lower Mantle, Transition Zone, Asthenosphere Upper Mantle, Continental Crust, Oceanic Crust. Mantel: is where earths convection works. The fact that the interior of the earth is hot and the surface is cool creates a thermal gradient. This gradient drives flow, where hot mantle rock rises beneath mid-ocean ridges. Cold, dense crustal rock is subsumed by the mantle and sink. Convection + Plate recycling is Wegeners missing mechanism.
Inorganic Mineral
No organic chemicals present (H-C bonds)
· What are the 3 types of faults?
Normal, Reverse/Thrust, and Strike-slip fault/ Look at photo from notes
2 types of body waves
P waves (Pulse) and S waves (Up and down kinda waves)
Pahoehoe (Helluhraun) versus Aa (Apalrhaun) - what are these? What's the difference?
Pahoehoe and Aa are two different types of lava flows. Pahoehoe is a smooth, ropy, billowy type of lava flow that has a uniform, glassy surface. It is usually formed by low-viscosity basaltic lava. Aa is a rough, jagged, blocky type of lava flow that has a spiny, sharp surface. It is usually formed by high-viscosity, basaltic lava. The difference between the two is mainly in their texture and the kind of lava from which they are formed.
Recycling of Crust:
Plate tectonic theory: The earth crust is made up of large blocks of crust called plates, these plates are constantly being recycled on a great conveyor belt
Ryolite
Rhyolite is a volcanic rock and can contain a variety of minerals, including quartz, plagioclase, biotite, hornblende, and augite. It may also contain traces of other minerals, such as muscovite, magnetite, hematite, and apatite.
What is the method by which we determine the mechanical properties of the earth's layers?
Seismic refreaction: The method by which we determine the mechanical properties of the earth's layers is seismology. Seismology involves measuring the propagation of seismic waves through the earth's layers. By measuring the speed and attenuation of the waves, it is possible to estimate the mechanical properties of the different layers.
Seismic wave velocities!
Seismic waves that radiate outward from the focus of an earthquake.
The silicon tetrahedron:
Silicon (Si+4) is typically surrounded by four oxygen atoms (O-2) to form a stable silicon tetrahedron (SiO4). This geometric structure is very strong, because the tiny silica atom nestles perfectly between four large oxygens, covalently bonded to each.
Mechanical Layers
Solid Crust Lower mantle: This region is highly ductile, meaning that it is capable of undergoing large amounts of deformation without fracturing. It is thought to be the source of most of Earth's volcanic activity and accounts for the majority of the Earth's internal heat energy. Upper Mantle: It is a mechanically weak zone, and is believed to be the source of magma that fuels volcanoes and is the site of most of Earth's seismic activity. The asthenosphere is composed of mostly solid rock that can flow like a liquid over geologic time scales. It lies between about 100 and 200 km (60 and 120 miles) beneath the Earth's surface and is composed of hot rock that is much less dense than the underlying mantle. Liquid outer core Solid inner core
What is super-rotation?
Super rotation is a term used to describe the rapid rotation of tectonic plates relative to the Earth's mantle. It occurs when one plate is subducted faster than it is created, resulting in a net rotation of the entire plate boundary. This process can cause dramatic changes in the Earth's surface, such as mountain building and earthquakes.
—> Seismic Waves: 2 main types of waves
Surface Waves, and Body Waves
Solid-Solid Reaction formation
THe formation of a mineral frome one or more pre-existing minerals. Squishing a mineral to change into a different mineral. This occurs in the solid state (no melting). This is done by subjecting the mineral to intense pressure and temperature conditions.
The Solidus:
The changes in pressure and temperature impact the phase of rock whether it is solid or liquid. The blue line is called the solidus and describes the boundary conditions between these thwo phases. Temperatures and pressure to the right of the solidus will melt rock. Bring the geotherm across the solidus by increasing the temp. This will cause the mantle and crust to melt generating magma
Biomineralization formation:
The formation of a mineral by a living organism. usuallyy either within, on, or immediately adjacent to the body. This is most commonly done by micriscopic and macroscopic plants and animals that live in the ocean.
What is the geotherm, what is the solidus? Why are these significant? Be familiar with this figure and how to use it to generate melt in the mantle
The geotherm is a graph of the temperature of the Earth as a function of depth. It is usually represented by a curved line that slopes upwards with increasing depth. The solidus is the temperature at which a solid-liquid phase transition occurs in a rock or mineral. It is the temperature at which the rock or mineral begins to melt.
What type of plate boundary? Type of fault? Turkey
The neotectonics of Turkey is governed by three major elements: (1) the Aegean-Cyprean Arc, a convergent plate boundary where the African Plate to the south is subducting beneath the Anatolian Plate to the north; (2) the dextral North Anatolian Fault Zone; and (3) the sinistral East Anatolian Fault Zone (figure 1).
What is tuff?
Tuff is a type of rock made up of compressed volcanic ash, which is created when ash and rock fragments are ejected from a volcanic eruption and solidify in the air or on the ground. It is usually light coloured and contains pieces of broken-up volcanic rock. Tuff is a common rock type in areas of volcanic activity.
How do temperature and pressure change as we move into the interior of the earth?
Velocity: Temperature and density/ Density, faster waves through dense material/ Temp faster through colder rock.
What are vesicles? How do they form?
Vesicles are small, air-filled cavities that form in rocks as a result of gas bubbles being trapped during the cooling and solidification of molten lava or magma. As the molten material cools and solidifies, the gas trapped in it expands and forms voids or vesicles in the rock. These vesicles can vary in size from microscopic to several centimeters in diameter. They can also be found in other types of rocks, such as sedimentary rocks and metamorphic rocks.
Who is Marie Tharp? What were her contributions that brought scientists back to Wegener's theory?
Wegener lacked the tools to explore a huge missing piece of the continental drift puzzle until Marie Tharp came along —> Marie Tharp, worked as a geologist and cartographer at Columbia University in 1952 With the help of Bruce Heeze, they both mapped downed military aircraft and location submarines with Sonar Waves. Marie generated the first map of the ocean floor using ship soundings and earthquakes She saw the mid continental ridge.
o Know what differentiates these classes (complexity, number of tetrahedral bonds, strength)
Why structure matters: The nature of atomic bonds controls characteristics. Sheets are a weak form of crystal bonding. Frameworks are a very strong form of bonding. Two minerals with the same chemical composition but differeing crystal structures are polymorphs. EX: Diamond and graphite are bth natice element minerals made entirely of carbon.
What type of stress produces folds?
compressional stress
Paleomagnetism
is the process by which iron minerals archive a magnetic signal from the deep past. At high temperatures in molten form, iron minerals are randomly oriented. As lava cools, minerals align with magnetic pole. Once the lava cools completely into rock, minerals are locked in place and can no longer move.
Fault Trace:
o : Fault trace, or fault line, is a line that marks the surface trace of a fault in geology. It is the visible expression of a fault plane, which is the plane at which a fault has moved. Fault traces are often seen on the landscape as linear features such as cliffs, ridges, and valleys. They are commonly seen in mountainous terrain and can also be seen in sedimentary rocks.
Footwall:
o A footwall fault is a type of fault in which the block of rock above the fault plane (the hanging wall) moves down relative to the block of rock below the fault plane (the footwall). This type of fault is often associated with thrust faults and reverse faults.
· Know the textural terms:
o Aphanitic o Glassy o Vesicular o Phaneritic o Porphyritic o Pegmatitic
· Where does volcanism occur? Where does most of it occur?
o At plate boundaries! § Spreading Centers (mid-ocean ridges) § Subduction zones o At hotspots! § Can occur underneath oceanic or continental crust
· 5 Types of Volcanoes
o Composite/Strato o Shield o Cinder o Mid-ocean ridge o Super
· Why is this fault geometry unusual in this part of California?
o Compressional stress! o What is a consequence of this? Mountain forming cheveron, recumbent folds o Plates involved? Pacific and North American Plate
· Viscosity and gas content are a function of magma chemistry
o Continental versus Oceanic crust (different chemistry) o SiO2 - key determinant for viscosity! More viscosity the more solid/ clumpy
· Plate Boundaries, the (Stresses), locations, and fault types
o Convergent (Compressive), Mountain Belts & Subduction Zones, Thrust/Reverse Faults o Divergent (Extensional), Mid-Ocean Ridges, Normal Faults o Transform (Shear) - strike-slip faults
· What is fractional crystallization? What is the major consequence of this process?
o Diversity of minerals and rocks on earth! Fractional Crystallizatio: The sequential removal of minerals from a melt as it cools Fractional crystallization is a process by which a mixture of different ionic compounds are separated by allowing them to precipitate out of a solution at different temperatures and concentrations. The major consequence of this process is the separation of the components of the mixture into their individual components, which can then be collected and used for various purposes.
· What comes out of a volcano?
o Gas o Magma o Ejecta § Tephra - generic term that includes the following: · Bombs · Lapilli · Ash § Pumice § Scoria
Why do volcanoes erupt?
o Gases! o Exsolution (decrease in pressure leads to gas formation) o Types of gases in volcanoes? § CO2, H2O, SO2
· 3 ways to generate melt!
o Increase Temperature (Hotspot melting) o Decrease Pressure (Decompression melting) o Change the melting point of rock (Partial Melting) make it cooler melting point
· What are the 3 terms to define folds
o Limbs, Hinge Line, & Axial Plane are terms used to describe folds
· Geology in the News: Turkey Earthquake
o Magnitude 7.8 earthquake in southern Turkey on Feb. 6 o
· Plate Tectonic Theory
o Mantle Convection Mantel: is where earths convection works. The fact that the interior of the earth is hot and the surface is cool creates a thermal gradient. This gradient drives flow, where hot mantle rock rises beneath mid-ocean ridges. Cold, dense crustal rock is subsumed by the mantle and sink. Convection + Plate recycling is Wegeners missing mechanism.
· What are the most abundant elements in the earth's crust, in the bulk earth?
o Need to know top 2 for both - but not beyond that : Together, oxygen and silicon make up 75% of the earths crust. Aluminum is 3rd most abundant (8%). Iron comprises more than 30% of the bulk earth but only 5% of the crust due to it being very dense. o Crust: Oxygen & Silicon, Bulk Earth: Oxygen & Iron
· What are the stages of deformation for a rock?
o Non-deformed o Tilting o Folding o Faulting
· Where do we find explosive volcanoes?
o Putting variables of temperature, viscosity, chemistry and plate tectonic setting together: strato volcanoes, super volcano California, Mild is cinder volcano
Ocean Observations: Sea Floor Spreading, what is this? Be able to explain
o Sea floor spreading cools magma in place much more rapidly. Continental crust is much thicker than oceanic crust which allows for a much greater distance traveled bethimitary, seeing the evidence of a rift valley and sea floor spreading.
· Viscosity controlled by 2 things
o SiO2 o Temperature the higher the temperature the lower the viscosity.
What are the 5 sub-types of folds? Be familiar with the shape and be able to ID these based on field images
o Symmetrical o Asymmetrical o Isoclinal o Recumbent o Chevron
· 2 Reasons why continental crust induces travel
o Thickness o Subduction forces travel through slab
Apparent Polar wander
the perceived movement of the Earth's paleo-magnetic poles relative to a continent while regarding the continent being studied as fixed in position. · the magnetic pole is fixed and the volcanic rock moving around the earth, this is apparent polar wander not just polar wander.
· What do we mean by the evolution of a magma? How does this happen? What impacts magma chemistry?
· 1. Distance traveled impacts whether a magma will be primitive or evoloved—— evoloved means more felsic. - temp imacts crystallization which changes melt chemistry · 2. Source material: impacts the type of magmas (and rock) you can create to begin with - Startng with hihg evoloved (felsic) · 3. imoacts whether you can change te magma chemistry. · Rocks fall into the magma chamber by degrading the literal walls of that chamber, these big blocks of minerals/rock float into the magma and can change the chemistry of the magma. · Oceanic: Mafic · Continental: felsic
What is a caldera? How does it form?
· A caldera is a large, circular depression in the ground which is caused by a volcanic eruption. It is formed when an erupting volcano collapses in on itself after emptying its magma chamber. The magma chamber is a reservoir of molten rock which feeds an active volcano. Once the magma chamber is emptied, the pressure supporting the volcano is released, causing the surface to collapse. The result is a large crater, or caldera, that can range from one to dozens of kilometers in diameter.
· What is the difference between an intrusive and extrusive igneous rock?
· A lava that cools on the earths surface forms an extrusive igneous rock. A magma that cools below te earths surface forms an intrusive igneous rock. · Fast cooling = extrusive, slow cooling= intrusive. · Rate of cooling affect rock texture: aphanitic rocks are intrusive while phaneritic rocks are extrusive. · Intrusive: cooled slowly at depth: did not come out of a volcano, must have been brought to surface by other means----> Phaneritic · Extrusive: cooled quickly on surface, and came out of volcano-----> Aphaneritic
Can earthquakes be predicted? At what scale?
· At the large global scale we can predict where but we do not where earthquakes will occur on the local/small scale. Can not specificaly place where a earthquake will occur.
Definite chemical composition mineral
· Can be represented by a chemical formula
· How does this impact the cooling rate of the rock?
· Fast cooling = extrusive, slow cooling= intrusive. Extrusive rock textures: Glassy: smooth, glassy appearance with no visible mineral grains... often exhibits conoidal fracture! Intrusive: cooled slowly at depth: did not come out of a volcano, must have been brought to surface by other means-----> Phaneritic Extrusive: cooled quickly on surface, and came out of volcano---- Aphanitic
What happened in La'Aquila, Italy?
· In 2009, an earthquake struck the city of L'Aquila, in the Abruzzo region of central Italy. The 6.3 magnitude earthquake killed 308 people and left thousands more homeless and injured. The destruction caused by the earthquake was extensive, with around 65,000 buildings damaged or destroyed. The city has since undergone a long process of rebuilding and restoration, with many of the original historical buildings being reconstructed.
Pinto Gneiss:
· Pinto Gneiss: The monozogranite intruded through something that was sitting on the continent above it... This is the Pinto Gneiss. Gneiss is a metamorphic rock that forms during mountain building and collisional process. · THe Pinto Gneiss formed during a massive supercontinent formation 700 million years ago.... Before Pangea. · Pillar formations: Jointing
Pinto Gneiss: and White Tank Monzogranite
· The White Tank Monzogranite and the Pinto Gneiss are both found in Joshua Tree. Another major feature present in Joshua tree are the parallel fractures present in the Monzogranite. THese are called joints and they form from changes in pressure or contraction associated with cooling magma. These joints genereate the characteristic boulders of Joshua tree! · Talking about above note —> Verticle cracks: formed via contraction cooling, Diagonal cracks: formed via compressional stress, and Horizontal cracks: formed via decrease in over-pressure
What are earthquakes?
· The sudden release of stored elastic strain energy by slip along faults
· How did the White Tank Monzogranite form?
· The white tank monzograntte is what we will see in Joshua tree. This rock is highly resistant to weathering and thus form tall pillars with time. This rock is a framework silicate=strongest rock. The white tank monozogranite started as a melting continental crust under north america 85 million years ago. The magma slowly cooled and formed a large batholith (large intrusive igneous body) in the subsurface.
San Andreas (info discussed in your lab) - what type of fault is this?
· Transform boundary strike slip fault. Right lateral strike slip
Alfred Wegeners five lines of evidence
· Wegener's 5 lines of evidence o Fit of the Continents o Glacial Evidence o Paleoclimatic Evidence o Fossil Evidence o Mountain Belt Tie Lines
What are faults?
· fractures in rock parallel to the fracture plane
Where do most volcanoes reside?
—> 90% of the rest of all volcanoes happen at the mid-Ocean ridges.
What are some of the main differences between oceanic and continental crust (e.g. density, thickness, composition)
—> Oceanic Crust: Dense and thin, Mafic igneous rocks, thin layer of marine sediment —> Continental Crust Light and thick, Felsic igneous rock, metamorphic rock and ect.