Geology Study Guide

Front 1

the principle that the geologic processes we see in action today have worked in much the same way throughout geologic time; that is "the present is the key to the past."

Back 1

uniformitarianism

Front 2

put in order, least to most dense: oceanic crust, continental crust, mantle rock, metallic iron

Back 2

continental crust, oceanic crust, mantle rock, metallic iron

Front 3

plate boundary that moves apart and creates new lithosphere

Back 3

divergent

Front 4

plate boundary that comes together and recycles oceanic lithosphere.

Back 4

convergent

Front 5

plate boundary where plates slide past each other

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transform fault

Front 6

mid ocean ridge is ________ plate boundary

Back 6

divergent

Front 7

Oceanic crust that is close to a mid-ocean ridge is (younger/older) than oceanic crust that is farther away from the mid-ocean ridge.

Back 7

younger

Front 8

subduction occurs when:
a. two plates made of oceanic crust come together.
b.a plate made of oceanic crust meets a plate with continental crust
c. two plates made of continental crust come together.
d. any of these is possible

Back 8

D. any of these is possible

Front 9

Mantle convection works by (hot/cool) material rising, and (hot/cool) material sinking.

Back 9

hot, cool.

Front 10

Hot material is (more/less) dense than cool material.

Back 10

less

Front 11

a naturally occurring, solid crystalline substance, generally inorganic, with a specific chemical combination.

Back 11

mineral

Front 12

bond between atoms formed by electrical attraction between ions of the opposite charge.

Back 12

ionic bond

Front 13

bond between atoms formed by sharing electrons.

Back 13

covalent bond

Front 14

covalent bond in which freely mobiel electrons are shared and dispersed among ions of metallic elements, which have the tendency to lost electrons and pack together as cations.

Back 14

metallic bond

Front 15

atomic number=______

Back 15

number of protons

Front 16

basic building block of silicate minerals

Back 16

silicate ion

Front 17

silicate ion= 1 ____ and 4 _____

Back 17

silicon, oxygen

Front 18

measure of the ease with which the surface of a mineral can be scratched.

Back 18

hardness

Front 19

tendency of a crystal to break along flat planar surfaces

Back 19

cleavage

Front 20

how the surface of a mineral reflects light

Back 20

luster

Front 21

a dark-colored igneous rock containing minerals rich in iron and magnesium and relatively poor in silica

Back 21

mafic rock

Front 22

an igneous rock midway in composition between mafic and felsic, neither as rich in silica as the felsic rocks nor as poor in it as the mafic rocks.

Back 22

intermediate igneous rock

Front 23

a light-colored igneous rock that is poor in iron and magnesium and rich in high-silica minerals such as quartz, orthoclase, feldspar, and plagioclase feldspar.

Back 23

felsic rock

Front 24

fast cooling igneous rocks are ______.

Back 24

extrusive

Front 25

slow cooling igneous rocks are _____.

Back 25

intrusive

Front 26

slow cooling = ____ grains.

Back 26

coarse

Front 27

fast cooling = _____ grains.

Back 27

fine

Front 28

all magmas that are generated in the mantle are _____ in composition.

Back 28

basaltic

Front 29

crystals formed in a cooling magma are segregated from the remaining liquid

Back 29

fractional crystallization

Front 30

magma melts part of country rock and it changes composition.

Back 30

assimilation

Front 31

two kinds of magma come together and form different composition

Back 31

magma mixing

Front 32

____ is the most common mineral in detrital sedimentary rocks.

Back 32

quartz

Front 33

the physical and chemical changes- including pressure, heat, and chemical reactions- by which buried sediments are lithified into sedimentary rocks.

Back 33

diagenesis

Front 34

three types of sedimentary rocks:

Back 34

chemical, biological, and clastic

Front 35

fine grained sedimentary rocks are formed from deposits that are (near to/far from) the source rock.

Back 35

far from

Front 36

rounded sedimentary grains represent (short/far) transport distance.

Back 36

far

Front 37

continental depositional environments

Back 37

lake, alluvial, desert

Front 38

shoreline depositional environments

Back 38

deltaic, tidal flat, beach

Front 39

marine depositional environments

Back 39

continental shelf, organic reefs, deep-sea

Front 40

put in order, low to high grade: phyllite, schist, slate, gneiss

Back 40

slate, phyllite, schist, gneiss

Front 41

foliated rocks are associated with _____ metamorphism.

Back 41

regional

Front 42

parent rock of quartzite:

Back 42

sandstone

Front 43

parent rock of marble:

Back 43

limestone

Front 44

parent rock of slate:

Back 44

shale

Front 45

parent rock of gneiss:

Back 45

shale

Front 46

lines drawn by geologists that show where one metamorphic grade changes to another.

Back 46

isograd

Front 47

three factors that can lead to metamorphism:

Back 47

heat, pressure, and fluids.

Front 48

metamorphic facies that represents highest temperature and pressure conditions

Back 48

granulite

Front 49

the tendency of rock to behave in a brittle or ductile way depends on the _____ and ____.

Back 49

pressure and temperature.

Front 50

fault at mid-ocean ridges:

Back 50

normal faulting

Front 51

actual number of years elapsed from a geologic event until now

Back 51

absolute age

Front 52

age of one geologic event in relation to another

Back 52

relative age

Front 53

principle that involves the use of fossils as tools for correlating rock units

Back 53

principle of faunal succession

Front 54

a fold where both limbs dip in the same direction is called ____.

Back 54

symmetrical (anticline)

Front 55

If a sample has 25% of the parent isotope and 75% of the daughter isotope in an isotope system with a half-life of 1 million years, then how hold is the sample?

Back 55

2 million years old.

Front 56

transformed random chunks of primordial matter into a body whose interior is divided into concentric layers that differ from one another both physically and chemically.

Back 56

differentiation

Front 57

How did differentiation shape the development of the earth?

Back 57

when the earth was soft, heavy materials sank to the center of the earth to make the core, and lighter material floated to the top to make the crust.

Front 58

three meteorites

Back 58

iron, stony, iron-stony

Front 59

earth is ___ years old.

Back 59

4.5 Ga

Front 60

The earth's oceans and atmospheres formed from gasses released by ____.

Back 60

volcanoes.

Front 61

Temperature and viscosity of Rhyolitic lava

Back 61

600-800 degrees, thick

Front 62

temp and viscosity of Andesitic lava

Back 62

lower temp than basaltic thick

Front 63

temp and viscosity of basaltic lava

Back 63

1000-1200 degrees, thin

Front 64

Aa lava and pahoehoe lava are both ____ in composition.

Back 64

basaltic

Front 65

____ are clouds of hot ash and rock that race down the flanks of a volcano during eruption of rhyolitic lava.

Back 65

pyroclastic flows

Front 66

the rock that is formed from the fusing of ash deposits is called ____.

Back 66

tuffs

Front 67

broad, shield-shaped volcano many tens of kilometers in circumference and more than 2 km high built by successive flows of fluid basaltic lava from a central vent.

Back 67

shield volcano

Front 68

concave-shaped volcano containing alternating layers of lava flows and beds of pyroclasts.

Back 68

stratovolcano

Front 69

a bowl-shaped pit found at the summit of most volcanoes, centered on the vent.

Back 69

crater

Front 70

a large, steep-walled, basin-shaped depression formed after a violent eruption in which large volumes of magma are discharged, when the overlying volcanic structure collapses catastrophically through the roof of the emptied magma chamber.

Back 70

caldera

Front 71

a volcanic vent formed by the explosive escape of gases and often filled with breccia.

Back 71

diatreme

Front 72

what type of eruption is commonly associated with flood basalts?

Back 72

fissure eruptions

Front 73

an earthquake begins at one point within the crust

Back 73

focus

Front 74

the point on the surface of the earth that is directly above the focus

Back 74

epicenter

Front 75

first wave to arrive, compressional, travels through solid rock, liquid, and gas

Back 75

Primary wave

Front 76

second wave to arrive, shear wave, travels through solid rock

Back 76

secondary wave

Front 77

third wave to arrive, ripples across earth's surface, and only travels through solid rock

Back 77

surface wave

Front 78

seismograph readings tell you:
a. how far away from an earthquake you are
b. what type of motion occurred on the fault
c. the Richter magnitude of the earthquake
d. all of the above

Back 78

D

Front 79

What directions do seismic waves travel away from the focus?

Back 79

all directions

Front 80

mirror image

Back 80

reflection

Front 81

change of direction of wave when passed through a different medium

Back 81

refraction

Front 82

property of rocks that determines the velocity at which seismic waves travel through them?

Back 82

density

Front 83

the time sequence of reversals of Earth's magnetic field as indicated in the fossil magnetic record of layered lava flows.

Back 83

magnetic stratigraphy

Front 84

components of the climate system

Back 84

atmosphere, cryosphere, biosphere, lithosphere, hydrosphere.

Front 85

when a change in one component is enhanced by changes it induces in other components.

Back 85

positive feedback

Front 86

when a change is reduced by the changes it induces in other components

Back 86

negative feedback

Front 87

three time scales on which temperatures on the earth change

Back 87

100,000 years, 1000 years, 30-50 years

Front 88

How have humans influenced climate in the past century?

Back 88

Humans have been putting more Carbon in the atmosphere since the industrial revolution.