Geology EXAM 2

Solifluction

Slow, downslope flow of water-saturated materials common to permafrost areas

waste disposal (radioactive decay), biological impact, mining locations, production of earthquakes/tsunamis

what are some concerns associated with the production of nuclear energy?

displacement, landslides, sediment liquefaction, tsunamis

what are some damages caused by earthquakes?

metamorphic grade

a measure of the intensity of temperature and pressure conditions that lead to alteration

moment magnitude

a more precise measure of earthquake magnitude than the Richter scale, which measures the amplitudes of several different seismic waves and determines the dimensions of the slipped area and estimate displacement

evaporites

a natural salt or mineral deposit left after the evaporation of a body of water; type of chemical sedimentary rock

superposition

a principle that states that originally younger rocks lie above older rocks if the layers have not been disturbed

hydrofracturing

a process that cracks subsurface rock using high-pressure water with additives and sand; used more today to stimulate wells because many are not permeable

sandstone

a sedimentary rock that is composed of different mineral compositions of sand-sized grains, and can be classified based on proportion of quartz, feldspar, and lithic and found in nearly every depositional environment

absolute dating

a technique used to date events using geologic 'clocks' and, depending on the dating method, have errors of years to millions of years; finds numerical ages; uncertainty scales with magnitude

glacial unconformity

a type of disconformity in which a glacier has come in--> eroded a lot of material and deposited new sediments on top

residual heat from planet formation and heat from radioactive decay in the crust and mantle

what are the 2 sources of geothermal energy?

l waves and r waves

what are the 2 type of surface waves?

shortening, stretching, shearing

what are the 3 S's that cause deformations?

liquid water load, surface slope, gravity

what are the 3 factors of hydraulic potential gradients dictating the flow of rivers?

biochemical, organic, chemical

what are the 3 types of non-clastic sedimentary rocks?

dissolved, suspended, and bed

what are the 3 types of sediment transport?

slope instability, planes of weakness, undercutting

what are the 3 ways to initiate mass movement?

Hadean, Archean, Proterozoic, Phanerozoic

what are the 4 eons from oldest to most recent?

mining and milling, conversion, enrichment, and fuel fabrication (can take place in different places)

what are the 4 major processing steps for nuclear fuel?

p waves

what are the first type of seismic waves to arrive at a station?

surface waves

what are the last type of seismic waves to arrive at a station?

wind, water, ice, and gravity

what are the modes of sediment transport?

s waves

what are the second type of seismic waves to arrive at a station?

compression (shortening of space)

what causes anticlines and synclines to form?

indonesia

what country has the largest capacity for geothermal expansion?

china

what country has the most coal?

Kazakhstan, canada, australia

what country is leading in mining production and reserves of uranium? what are the countries following it?

france

what country is the leader of providing the most energy in the nuclear energy of their total electricity generation?

united states

what country is the top leader of nuclear electricity generation capacity?

russia

what country produces the most nuclear fuel during enrichment?

atmospheric patterns, ocean circulation, animal migration/isolation, and continentality

what did the break-up of supercontinents influence?

vertical displacement pushes water up--> gravity pulls the bulge down--> up-down motion begins

what generates tsunamis?

sand grains and smaller

what grain size can wind transport move?

continental rifting

what is a result of stretching?

moment magnitude

what is now the most widely used form of magnitude?

uranium ore

what is the choice material for nuclear fuel?

marine environments

what is the depositional environment of most source rocks for oil and gas?

between 70-80 and 81-98 mW/m^2

what is the global average of heat flux at the surface?

area/wetted perimeter

what is the hydraulic radius equal to?

Paleozoic, Mesozoic, Cenozoic

what is the order of eras of the Phanerozoic Eon (oldest to most recent)?

wind, sand

what kind of sediment transport can move sediments across continents? what size sediments can it move?

population density, distance from epicenter, nature, types of buildings, after effects, sediment type

what other factors influence earthquake damages?

wastewater disposal

what part of hydrofracturing really causes earthquakes to occur?

fine grains

what size grains are typical carried in a suspended load?

large rainfall events

what speeds up the process of slumping?

250-850 degrees celsius

what temperatures does metamorphism occur between?

strike-slip fault

what type of boundary does shear stresses occur at?

peat

what type of coal has the least amount of carbon and the greatest amount of volatile compounds?

anoxic environments

what type of environment is critical to forming oil and gas?

convergent

what type of plate boundary does compressive stresses occur at?

divergent

what type of plate boundary does tensional stresses occur at?

clastic

what type of sedimentary rock makes up 3/4 of all sedimentary rocks?

pull/extensional

what type of stress produces normal faults?

push/compressive

what type of stress produces reverse faults?

push/compressive

what type of stress produces thrust faults?

shear

what type of stress produces transform faults?

l waves

what type of surface waves are the most damaging?

convergent

what type of tectonic boundaries do accretionary prisms form at?

geometry of channel itself

when calculating a river's discharge, the area reflects the _____

2.3 billion years ago

when does the atmosphere become oxygen-rich?

4.5 billion years ago

when was the formation of earth?

all major continents

where are Proterozoic shields commonly found globally?

rivers

where are conglomerates likely to be found?

water source

where are nuclear power plants always located near?

low elevations

where are river channels likely to be found?

low elevations by ridges of mountains

where are river channels likely to be found?

East Antarctic and African

where are the 2 largest Proterozoic shields located?

North America

where are the most Archean cratons found?

middle east

where are the most oil reservoirs located?

swamp and marshes

where does coal form?

inside a nuclear power plant

where does fission take place?

Gulf of Mexico

where does most of the rivers in the US drain into?

landslides

where is breccia likely to be found?

glacial environments

where is diamictite likely to be found?

sedimentary rocks

where is the largest pool (reservoir) of carbon on earth?

west

where is the most coal located in the US?

fault line/trace

where you can see the fault on the surface

deeper, narrower

will a shallow, wide channel or a deeper, narrower channel be more efficient at draining water?

strike-slip fault

a type of fault where rocks on either side move past each other sideways with little up or down motion; occurs at transform boundaries; due to shear stress

fission

currently used to yield tremendous quantities of energy used to run nuclear power plants

increase, decrease

higher coal grade--> ___ in carbon content and a ____ in volatile compounds

greater

higher grade coal such as bituminous and anthracite form at ______ temperatures and pressures

strict rules, lots of data, and debates

how are time scales determined?

99

how many nuclear reactors are there in the US?

20%

how much of the US's total electricity generation is nuclear?

angularity

how round/angular grain edges are

earthquakes

hydrofracturing can cause ____

angular

if edges of sediment are ___ --> indicates shorter distances traveled and less time

cross-cutting relations

if one geologic feature cuts across another, the feature that has been cut is older

greater

if there is an increase in friction--> there is ____ resistance of downslope movement

decrease

increase in vegetation--> ___ in erosion

angular edges

indicate that the sedimentary rock has not moved far from its depositional source

rounded edges

indicate that the sedimentary rock has travelled longer distances and for a longer amount of time bumping into things along the way--> has been transported a farther distance away from its depositional source

grain composition

indicates resistiveness, mixing processes, and sorting processes

point bar

inside ends of the bends of a river; where sediment builds up; slower velocity

decreases

intensity ____ from the epicenter of an earthquake

paleocurrents

it is important to measure ____ in the sediments in addition to measuring the strike and dip

surface waves

l and r waves arrive at any particular point on the surface substantially after the arrival of body waves

focus

location where seismic waves are first generated

burial metamorphism

low-grade metamorphism that is caused by the deep burial in a basin

natural gas and coal

make up 30% of world energy use

dissolved load

material that is chemically carried in the water

pressure solution

metamorphic process in which mineral grains partially dissolve where their surfaces press together--> dissolved ions migrate in a thin water film and reprecipitate in areas where pressure is low

deformation

metamorphic process in which mineral grains soften and deform when rock is squeezed or sheared at elevated temperature and pressure--> minerals change shape without breaking, behaving like a plastic

recrystallization

metamorphic process in which minerals change size and shape through dissolution and growth of crystals; the composition of the minerals does not change

phase change

metamorphic process that is a change from one mineral to another mineral of the same composition, but different crystalline structure (atoms rearrange)

neocrystallization

metamorphic process that is the formation of new metamorphic minerals from old minerals, as they become unstable and undergo chemical reactions that recycle elements to form a new mineral assemblage

tree rings

method of absolute dating based on correlation of ring patterns--> high accuracy, but limited range method of dating

rhythmic dating

method of absolute dating which uses seasonal or annual layers of sediment, ice, and tree rings (ages since inception of record)

sediment transport by water

method of transport of sediments in which MORE energy is required to entrain (lift) grains from the bed than to keep them in motion

radiometric dating

method that uses naturally decaying isotopes to determine ages; type of absolute dating

maturity

mineralogical, sorting, angularity and is influenced by time

sediment transport by wind

mode of transport of sediments in which low density, low viscosity "fluid" and the principles of entrainment, transport, and deposition, are similar to those for water

leave a small footprint, emit no greenhouse gases, and require less water

modern closed-loop geothermal power plants are considered 'clean' because they ____.

clastic sedimentary rocks

most common sedimentary rocks; made up of mostly silicate sediments bound together; important source of earth's resources

source, reservoir, trap

need a ___ of fossil fuels, a ____ to store it and a ___ so you are able to exploit it

non-clastic sedimentary rocks

not composed of pre-existing rocks; usually formed from a chemical reaction

intermediate-focused earthquakes

occur between 60-300 km of the earth

deep-focus earthquakes

occur down to a depth of 660 km (limit-- cannot occur any deeper than this)

shallow-focus earthquakes

occur within 60 km of the Earth (most within 5-20 km)

metamorphism

occurs due to pressure, temperature, stress, and chemically active fluids causing mineral and textural changes in rocks while rock is still in solid phase

creep

occurs when sediments slowly shift their positions downhill; process happens slowly over time as it adjusts to the bed changing below

economic stability

oil reservoirs are important for estimating ____

Diamictite

sedimentary rock composed of large clasts (gravel and larger) of varying degrees of angularity/roundness with an abundant fine-grained matrix and is poorly-sorted

conglomerate

sedimentary rock composed of rounded gravel, pebbles, cobbles, or boulders along with smaller sediments; travel longer distances (rounded edges)

bed load

sediments transported along the bed by sliding, rolling, or hopping

l waves (love waves)

seismic surface waves that are shear waves that cause the ground to shimmy back and forth and are the most damaging

r waves (Rayleigh waves)

seismic surface waves that are shear waves that cause the ground to undulate up and down

S wave patterns

seismic wave patterns that travel from the epicenter out around the core only staying within the mantle--> travel out to the sides

p wave patterns

seismic wave patterns that travel out from the epicenter in all directions and pass through the core and mantle; are refracted when they pass through the core

crust

seismic waves are felt when they reach the _____

surface waves

seismic waves that travel along the Earth's surface; slowest waves

body waves

seismic waves that travel through the interior of Earth

source

shale and limestone are ___ of carbon

s waves

shear body waves and travel at about 60% of the speed of the other type of body waves; only pass through the mantle (solid)--> cannot travel through liquid core

dynamic metamorphism

shearing in a fault zone

aftershock

shock that occurs after the main shock and is usually 10x smaller than the main shock

compressional

shortening =

sorting

similarity of grain size/shape

little organisms (diatoms, microorganisms, etc)

what are responsible for creating carbon and trapping it in the ocean?

waste disposal, biological impact, mining locations, production of earthquakes/tsunamis

what are some concerns associated with nuclear

thermal metamorphism

heating by a plutonic intrusion

subduction metamorphism

high pressure and low temperature alteration

solifluction and creep

2 examples of slow processes that can occur on steep slopes that are prone to failure?

footwall and hanging wall

2 walls associated with faulting

strike-slip behavior originating from pre-existing faults or energy released from previously intact rock

2 ways earthquakes can be generated

crude oil, natural gas, coal

3 types of fossil fuels

push, pull, shear

3 types of stress at a fault

oil

33% of world energy use was ____

magma intrusion beneath a volcano, landslides, meteor impacts, fracking

4 reasons why an earthquake may occur?

biochemical sedimentary rocks

A sedimentary rock that forms from the chemical activities of organisms; ex: chalk, micrite, chert

syncline

A downward fold in rock formed by compression (shortening of space); bowl shaped feature

fossil succession

A relative dating principle (w/ mix of absolute dating) stating that fossil organisms succeed one another in a definite, irreversible, determinable order; the age succession of fossils in the outcrop are used to date rocks

normal fault

A type of fault where the hanging wall slides downward and the footwall slides upward; caused by tension (pull) in the crust; footwall block on the left and hanging wall block on the right; occurs at divergent boundaries

foliation

Caused by differential stress--> extensive high-T shearing; banded appearance; develops perpendicular to compression, minerals flatten, recrystallize, and rotate; inequant grains align by rotation and new growth

Archean Eon

Eon extending from the time that life originated, 3.8 billion years ago, to 2.5 billion years ago

epicenter

Point on Earth's surface directly above an earthquake's focus

lateral continuity

Principle that states that layers continue laterally until they thin out to nothing (pinch out) and then later can be cut by erosional processes

slumping

Rapid mass movement which involves a whole segment of the cliff moving down-slope along a saturated shear-plane or line of weakness; material moves downslope rapidly

liquids

S waves cannot travel through while p waves can

footwall

The block of rock that forms the lower half of a fault-- below the fault; rock mass below the fault plane

hanging wall

The block of rock that forms the upper half of a fault-- above the fault; rock mass above the sloping fault

accretionary prism

The build up of sediments along the subduction plate margin; squeezed and uplifted--> with the highest and deepest part closest to the subduction zone-- root is under the highest part of the mountain

Holocene Epoch

The current interglaciation period, extending from 10,000 years ago to the present on the geologic time scale.

Hadean Eon

The earliest period in Earth's history-- 4.5 to 4.0 billion years ago

Phanerozoic Eon

The most recent eon, an interval of time from 542 Ma to the present.

stratigraphic correlation

The process of matching up strata from several sites through the analysis of chemical, physical, and other properties; powerful tool for understanding subsurface and exploiting the subsurface (for fossil fuels)

p waves and s waves

What are the 2 types of body waves?

planes of weakness

Zones of weakness caused by expansion due to batholiths

round

___ edges indicates farther distances traveled and for more time

faulting

___ is a result of brittle failure

earthquakes, tsunamis

____ --> landslides --> ____

time-travel curves

____ indicate the time delay between p waves and s waves

velocity

____ of water affects how much energy is required to lift grains from the bed and to keep them in motion

smaller, larger

____ rivers join with ____ ones-->____ in stream order as larger rivers are formed

local measurements

_____ are taken of heat flux at the surface and then interpolated to create a map of the global heat flux at the surface

greater

a ___ hydraulic radius will be more efficient--> less in contact with the bed--> less friction

shorter, longer

a bed load will move ___ distances and a suspended load can move ____ distances

fault scarp

a cliff created by movement along a fault--> it represents the exposed surface of the fault prior to modification by weathering and erosion

hydraulic radius

a measure of how much of the flow is in contact with the bed

reverse fault

a type of fault where the hanging wall slides upward and the footwall slides downward; caused by compression (push) in the crust; hanging wall on the left and footwall on the right; 60 degree angle; occurs at convergent boundaries

quantitative

absolute dating provides ____ data

hydrothermal metamorphism

alteration by hot water leaching

stick-slip behavior

alternation between stress buildup and earthquake generating slip events on a fault

anticline

an upward fold in rock formed by compression (shortening of space); like a hill

angular unconformity

angle/orientation of rock above and below a boundary do not align or match up

pairs

anticlines and synclines often occur in ____

pre-existing fault earthquakes

as stress builds across a frictionally locked fault, rocks adjacent to the fault bend elastically--> when friction becomes great enough that the anchor like bumps break or scratch a furrow in the opposite wall, the fault slips again

folds

bends that form by shearing and/or by slow plastic flow

disconformity

boundaries defined by an erosional surface representing a hiatus in time between underlying and overlying deposits

nonconformity

boundaries marked by sediments/sedimentary rock on bed rock/basement rocks (from in subsurface and are exposed at surface)-- sedimentary rocks on top of igneous or metamorphic rocks

crystallization; biochemical

calcite forms through ___ of shells from oysters, clams, etc. and is an example of a _____ sedimentary rock

strain

change in shape via deformation--> creates geological structures

shearing

changing orientation

sheetwash, gravity

channel initiation begins when ____ starts flowing downslope due to ____

travertine

chemical sedimentary rock composed of calcium carbonate and precipitated from ground water; found in caves and hot or cold water springs

dolostone

chemical sedimentary rock formed by a reaction between solid calcite and magnesium bearing groundwater

chemically precipitated chert

chemical sedimentary rock formed when other material is replaced by microcrystalline quartz; ex: quartz replaces calcite in limestone

grain size

classifications based on size ranges

larger, extreme

climate gradients on supercontinents were ___ and more ____

relative dating

comparative method of dating the older of two or more fossils/sites, rather than providing a specific date; puts geological events in chronological order without requiring a specific numerical age be assigned to each event

shortening

compression of space, material is being squeezed into a small space, forming mountains

p waves

compressional body waves that travel the fastest and increase with pressure and temperature; can travel through solids and liquids

organic sedimentary rocks

consists primarily of carbon-rich relicts of plants or other organisms; formed through burial and lithification; ex: oil shale, and coal

protolith

controls the initial mineral composition of a metamorphic rock

watersheds

define where water (or drainage basins) ultimately drain

distortion and displacement

deformation results in ____

denudation

destruction of mountains by erosion

velocity x area

discharge equals:

Richter scale

earthquake magnitude is measured on the logarithmic ____

elastic strain energy

energy that is released when the rock straightens out and generates earthquake vibrations

pressure

equal magnitude in all directions

East African Rift

example of a continental rift where tensional stresses stretch and pull rocks apart producing a normal fault

San Andreas Fault

example of a strike-slip fault

slumping, lahars, mudflows, debris flows, rockfalls, and landslides

examples of fast processes that can occur on steep slopes that are prone to failure?

vegetation accumulates in oxygen poor water, peat accumulation, buried and heated, chemical reactions drive off hydrogen, nitrogen and sulfur as gases and leave remaining residue coal made of about 70% carbon

explain the process of coal formation

shock metamorphism

extreme high pressure from an impact

fault displacement

fault slips tells us about the direction of _____

active or inactive

faults can be ___ or ____

hydraulic potential gradients

flow of rivers is driven by ____

chemical sedimentary rocks

formed primarily by minerals precipitated directly from water solutions

joints

fractures that have no offset

heat flux is high

geothermal expansion is tied to where ____ at the surface

high grade

grade of metamorphism that occurs at high temperature and pressure

low grade

grade of metamorphism that occurs at low pressure and low temperature

earthquake

ground shaking due to a release of energy that propagates through the crust of the Earth

cut banks

outside of the bends of a river where sediment is being eroded; faster velocity

solids

p waves and S waves can both travel through ___

pressure and temperature

p waves increase with ___ and ____

Shield

part of a craton in which the usually Precambrian basement rocks crop out extensively at the surface, surrounded by sedimentary rocks and/or sediments--> Proterozoic

suspended load

particulate sediment that is carried in the body of the flow

faults

planar breaks in the crust marked by offset of the two walls; a fracture plane on which sliding takes place

regional metamorphism

pressure and temperature change due to orogenesis

original horizontality

principle stating that sediments are deposited originally horizontally and can become tilted over time--> caused by tectonics, earthquakes, degree of metamorphism; oldest=bottom and youngest=top

Uniformitarianism

principle stating that the processes observed today were the same in the past; including tectonics, earthquakes, river processes, beach deposition, marine organisms collecting on seafloor; present is the key to the past and the past is the key to the future

fission

process involving certain radioactive atoms that can be fragmented to produce a great amount of nuclear energy

orogenesis

process of mountain building

late Anthropocene start

proposal that human impacts on the environment surged in the mid-twentieth century, a trend visible in many records and that radioactive fallout from nuclear blasts peaked in the mid-twentieth centering, leaving a signal visible in sediments

early Anthropocene start

proposal that humans began transforming the land surface thousands of years ago, through agriculture and other activities; one potential stratigraphic marker is a rise in the atmospheric concentration of methane millennia ago which is recorded in glacial ice--> could reflect increases in farming and animal herding

earthquake intensity

refers to the degree of ground shaking at a particular locality

qualitative

relative dating provides ____ data

primary productivity

river sediment delivery to ocean feeds _____

permanent rivers

rivers in which water is flowing all year and are common where there is abundant rainfall, groundwater discharge and low rates of evaporation

ephemeral rivers

rivers that do not flow all year and are common in places with low annual rainfall, a low water table, and high rates of evaporation

continental shelves

sediment deposition from rivers builds up on _____

breccia

sedimentary rock composed of gravel, pebbles, cobbles, or boulders; have a sharper, angular shape; deposited very near the source area

cyanobacteria

simple, single-celled organisms that came to life ~3.5 Ga (blue-green algae) and is thought to be one of the earliest forms of life on Earth and added more oxygen to the atmosphere through photosynthesis; form bacterial mats called stromatolites

foreshocks

smaller shocks preceding the major earthquake

stretching

solid earth behaves in different manners--> evidence of brittle failure of the crust; forms ridges and basins as landscapes are being pulled apart

craton

stable part of continental crust that has survived the merging and splitting of continents and supercontinents for at least 500 million years--> Archean

more

steeper slope--> ___ unstable

shear stress

stress parallel to plane

normal stress

stress perpendicular to plane

differential stress

stress that is greater in one direction

extensional

stretching =

perpendicular

strike and dip are always ____ to each other

seismology

study of earthquakes and the waves that propagate from them

tsunamis

submarine landslides could generate ____

downslope

surface water moves ____

slowest

surface waves are the _____

high, low

the United States has ___ current capacity for geothermal production and ___ additional capacity under development

displacement

the amount of movement across a fault

dip

the angle that a rock surface makes with a horizontal plane (cross-section orientation); angle!!

Modified Mercalli intensity scale

the damage of the earthquake and people's perception of the shaking

seismogram

the data record from a seismograph depicting the earthquake wave behavior, particularly the arrival times of the different waves, which are used to determine the distance to the epicenter

tectonic activity

the depth to the temperature variation in which metamorphism takes place varies with _____

strike

the direction of the line formed by the intersection of a rock surface with a horizontal plane (map direction); compass direction

earthquake magnitude

the energy released from the seismic source as recorded by the amplitude of ground shaking

deep time

the immense, almost unimaginable, span of geologic time

4x, 20x

the life cycle of GHG emissions from geothermal plants are ___ less than solar and up to ___ lower than natural gas

local magnitude

the logarithmic Richter scale measures _____

non-foliation

the metamorphic rock texture in which mineral grains are not arranged in planes or bands; no planar fabric because they lack inequant minerals and/or they recrystallized without differential stress, and they typically lack original textures and fossils in the limestone or dolostone protolith

4.8

the oldest tree is ____ thousand years old

Precambrian

the time span ranging from the formation of Earth 4.56 billion years ago to about 542 million years ago

elastic rebound theory

theory that rocks that are strained past a certain point will fracture and spring back to their original shape; the fundamental theory behind earthquakes forming from previously intact rock or pre-existing faults

Proterozoic Eon

time period ranging from 2,500 and 542 million years ago--> free oxygen, multi-cellular organisms.

anthracite

type of coal containing the most carbon; takes the longest time to form; loses volatile compounds through burial and lithification

thrust fault

type of reverse fault in which the fault plane is nearly horizontal rather than vertical; 30 degree angle instead of 60 degree

ocean

ultimate place rivers want to drain into is ___

settling velocity

velocity at which grains can resettle back to the bed

eroded, deposited

velocity variations in rivers are important for where sediment is ___ and ____

high, low, least

water flows from areas of ___ elevation to areas of ___ elevation along the path of ___ resistance

undercutting

wave erosion--> causes thinning at the bottom of a rock cliff--> causes it to become weak and fall

tsunamis

wave produced by displacement of the seafloor; can be produced by earthquakes

sediment liquefaction

wet sand grains settle together and the pressure in the water filling the space in pores between grains increases which leads to quicksand and quick clay--> slumping and settling

downslope forces (gravity) and resisting forces

what 2 forces initiate mass movement?

water flow velocity, bed resistance, and amount of vegetation

what 3 factors does erosion depend on?

topography, type of river bed, climate, vegetation

what 4 factors does the amount of transported material depend on?

increase in erosion or sediment transport with urbanization and agriculture, rapid changes in biosphere, abruptions in carbon, nitrogen, and phosphorous cycles

what are a few markers that could define the Anthropocene?

open pit mines

what are notorious polluters of water supply?