Exam 2

the force over the area the foce is being put on, equal to pressure

the change in shape due to stress

normal, thrust, strike-slip

marks the position along the fault where the plate motion occured. After shocks will clearly mark the location of the plate motion

the cycle of plates building up elastic strain as they interact and releasing it. After the plates release the elastic strain, they start building it again as they continue moving. Earthquake timings are still impossible to predict

made by seismologist Charles Richter. It is a logarithmic scale based on the movement of the ground in microns on a standard seismometer 100km from the epicenter. check slide 35 and 36 of faults and earthquakes, there will be questions directly off of those slides.

happened offshore of northeast Japan, caused a major tsunami

the aftershock epicenters were located all around the main epicenter of the 2011 Tohoku earthquake, but mostly towards the plate boundary

you have to know its a logarithmic scale, so one unit increase means 10X the ground motion. energy release is different though: one unit on the scale means there is 40X energy released

this scale is based on interviewing people and asking what they felt because of the earthquake. (just seismic monitors up to buildings collapsing)

about 5% of earthquakes happens in the middle of a plate, not at a boundary.

shows color depicting high risk areas for damaging earthquakes, by USGS. We do not know when big earthquakes will happen, but we can guess where they will happen

do not run outside, something will fall on your head. You're supposed to get under cover and hold on to something heavy

cycles per second

time between exact points on a wave

if an earthquake hits a building at its resonance frequency, it hits significantly harder. best way I can explain it is like pushing someone on a swing at the right time. if you just choose random times to push someone on a swing, it will not be as effective as waiting for them to start going down before you start pushing.

every building has a frequency that it is weaker at. when motion at a given frequency is amplified by waves or some other force at the same frequency

as loose dirt is moved around it becomes like liquid. having liquid in the dirt really doesnt help

a tsunami forms at a subduction zone by a great earthquake (magnitude 8 or higher) tsunamis do not crest and break, they inundate! (that is on the test)

impermanent change in a rock due to stress. when the weight is removed from the rock, the rock goes back to its original shape. its like letting go of a rubber band except it causes an earthquake.

if a seismic wave has the same frequency as a building's resonance frequency, the building will sway back and forth.

a bridge that was knocked down by wind hitting it at its resonance frequency.

as a seismic wave travels into material that is less rigid, it gets amplified because the seismic velocity of the material is so much lower. The wave will go from high frequency and high velocity and high amplitude to low frequency and low velocity and high amplitude.

1: convergent plates are locked together (reverse[thrust] fault). 2: the elastic strain is finally released all at once. This causes a water bulge directly above the fault. 3: as the water bulge collapses, it sends a wave outwards in every direction at extremely high speed. as the wave propagates through the water it becomes a tsunami.

as it goes through the ocean, the tsunami wave moves extremely fast. but as it gets into shallow territory, the front of the tsunami slows down and has nowhere else to go but up. (that's what shoaling is.)

remember a tsunami does not crest and break like a normal wave. it looks more like the level of the ocean itself rises and floods the land. This is called inundation.

the final distance that the tsunami travels to inland from the normal shoreline.

another big danger of earthquakes, normally caused by liquefaction on a hill or a mountain

naturally occuring inorganic solid, definite chemical composition, orderly arrangement of atoms (crystalline structure

an aggregate of minerals

for us, organic means produced by the soft tissue inside of a living thing (like flesh or wood or whatever but not bone apparently)

in minerals, the atomic structure will be consistent and form a pattern all the way through the mineral

has no crystal structure/definite chemical composition

this IS actually mineral material, because the organic stuff (C, H, and O) have been replaced by Si and O (silicon and oxygen)

not quite a mineral

usually minerals by different names. gems are normally large and well-formed crystals that have been cleaned up of imperfections

this mineral is chemically innert; it resists chemical weathering and abrasion/mechanical breakdown. most beach sand here is quartz

most shells at the beach are made of this, and it IS a mineral

coal is made of the soft tissue of living matter and is not a mineral because it is the remains of plant material

its a mineral :)

it is an erosional outlier; it is somehow resistant to the process of weathering and erosion which makes it stand out from the landscape around it that has been flattened for millions of years

breaking down/dissolving of rocks and minerals on earth's surface. remember the number one driving force behind this is water.

the action of moving weathered rock from one place to another. again it is water that does this.

creation, breakdown, reconstitution, metamorphism

melting and crystallization: this is what happens when rocks come out of volcanoes (so like the mid ocean ridge OR big continental volcanoes)

weathering and erosion: weathering is the mechanical and chemical breakdown of rocks/minerals exposed to earth-surface conditions. Erosion is the collective processes that carry the products of weathering from the place where the are formed to the place where they are deposited. The driving force behind all of this is water.

deposition-burial-lithification: happens when sediment particles are transported by water and are deposited in ocean basins and low-lying areas on the continents

deformation, deep burial, reheating and recrystallization

sediment, soil, dissolved ions

shale is basically just solidified mud; but then as it gets recrystallized by heat and pressure under the ground, the chemical structure of the rock is changed and it becomes gneiss

yes because it meets all of the definitions of a mineral even though it is one element.

collectively the particles that make up sand, silt, and clay

sediment mixed with organic matter

chemical elements dissolved in water, produced mostly by chemical weathering of rock.

enter definition (ill do it later but for now ig know that the ocean floor is pretty much all basalt)

we learned that if you melt basalt, they are rich in Fe and Mg through experimental petrology

means it contains very high concentrations of Fe an Mg

melting that happens due to air expanding (look this one up)

dont have that one yet

convergent plate boundary, compression. Remember it logically makes sense that these faults tend to form mountains because 2 crust masses are being pushed together.

convergent boundary, reverse (thrust) fault

normal fault, tension

divergent plate boundary, tension

normal fault, divergent plate boundary

strike-slip fault, shearing

transform plate boundary, shearing

transform plate boundary, strike-slip fault

at a normal fault, the hanging wall goes down

at a normal fault, the footwall goes up