geology final exam

Integration of biology and geology in the study of fossils/history of life on earth

paleontology

Ga

Giga annum: billions of years ago

Mesozoic

middle life

the terms jurassic, triassic, and cretaceous refer to

periods

other than earth, the terrestrial planets are

mercury, venus, and mars

what dominates the chemical composition of earth but only 5% of earths crust

iron

present day earths core is dominated by

iron and nickel

copernicus, kepler, galileo, and newton believed the universe had a ___ structure

heliocentric

the Big Bang occurred

13.7 billion years ago

our solar system lies near the outer edge of the

Milky Way

approximantely of the earths surface is covered with land

30%

the atmosphere is described as

a heat-softened relatively weak layer, 200 to 300 km thick in earths upper mantle

according to popular theory, the moon resulted from

an impact of a mars-sized object on the earth

geophysical evidence indicates that earths inner core is

solid

the density of earths core is

Twice of the whole earth. 10-13 g/cm

recent and ongoing collision of the Indian subcontinent and Asia has resulted in

Himalayan mountains

the Red Sea is a result of

recent rifting of Saudi Arabia

mid 1900s ideals regarding the force behind plate motion were determined by

convection in the upper mantle

Antonio Snider-Pellegrini

published his theory of continental drift in 1912

what relates perfectly to a "hot spot" (mantle plume)

Hawaiian islands

oceanic crust is

youngest near a mid-ocean ridge and is progressively older at greater distance from ridge

SONAR

allowed mapping of ocean floor

Sir Francis Bacon

made maps that showed how South America and Africa drifted apart

in tectonic plate settings, the Japanese islands most perfectly relate to

convergent plate boundary

yellowstone relates most perfectly to a

hot spot (mantle plume)

earthquakes that occur in the subjected lithosphere define the

Benioff (wadati-banioff) zone

oceanic crust and lithosphere produces in the

convergent plate boundary

minerals that are polymorphs have

the same chemical formula

What defines a mineral?

\- Homogeneous\- Naturally Occurring\- Solid\- Inorganic\- Well-defined Chemical Composition\-Crystalline Structure

the solubility of halite (NaCl) can be attributed to its

ionic bonds

when molten rock freezes into a solid so quickly that atoms and ions don't have time to join together it is called

glass

the presence of water (volatiles)

causes melting at lower temp than it would dry

the earths atmosphere contains 78% nitrogen and 21%

oxygen

in terms of tectonic setting, the Red Sea relates to

divergent plate boundary

the solubility of the mineral halite can be attributed to its

ionic bonds

glass isn't a mineral because

it doesn't have a highly ordered arrangement of atoms

ash that falls from the sky and is cemented or welded is

tuff

what kind of volcano has very gentle slopes and flows of low viscosity basalt

shield

Harry Hess

Proposed the theory of sea-floor spreading

a mafic igneous rock is

relatively low in silica content

as a mechanism of physical weathering, frost wedging is most effective

at mid latitudes characterized by moist temperatures climates

what mineral is most stable is weathering conditions

quartz

oxidation of iron-rich silicate minerals produces

hematite

when physical weathering breaks rocks into smaller pieces

the total surface area of the smaller pieces is more than original rock

in what environment would you least expect to find gravel

deep marine

fragments of rock that are transported by water currents

are sorted by size, become smaller, become rounded

Peat and coal formation

when vegetation is preserved and subjected to a lot of heat and pressure

steps of forming clastic sedimentary rocks

weathering, transport of product, deposition, and lithification

in terms of depositional environment , a lake is known as

lacustrine

a turbidite results from

underwater landslide

the most common cementing substances in clastic sedimentary rocks

calcium carbonate, silica, and iron oxide

shale is most perfectly distinguished among mudstone by

its tendency to split into sheets

blue schist is a product of

high pressure metamorphism

hypothermal metamorphism is most common

at mid ocean ridges where it relates to fluid vents called black smoker

what is the greatest contributor to contact metamorphism

heat

what is the highest grade metamorphic rock

biotite-garnet schist

fine grained nonfoliated rock

hornfels

foliation in metamorphic rock is attributed to

differential stress

metasomatism

the process by which a rock's overall chemical composition changes during metamorphism because of reactions with hot water that bring in or remove elements

formed by the recrystallization of limestone

marble

rock cycle steps

diagenesis, sedimentation, melting, metamorphism

The deadliest earthquake in history was in:

China in 1556

side to side horizontal motion wave

love waves

most earthquakes are associated with

faults

Seismogaph works by

means of a delicate suspended mass that tends to remain stationary when ground moves

Epicenter

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

Mercalli scale

A scale that rates earthquakes according to their intensity and how much damage they cause at a particular place

earthquake magnitude

represents the amount of energy released from the source

earthquake intensity

the degree of ground shaking at that locality

amplitude

the amount of back and forth and up and down of the ground, larger amplitude is greater deflection of seismometer pen

where do earthquakes happen

seismic belts or seismic zones; along faults

how do earthquakes cause damage?

Ground shaking and displacementLandslidesSediment liquefactionFireTsunamisDisease

`why do earthquakes occur on faults

bc the relative motion of plate boundaries causes slips

S-wave shadow zone

Those areas more than 103 degrees from an earthquake focus where no S-waves are recorded.

seismic tomography

A method that uses the seismic waves from earthquakes recorded on thousands of seismographs all over the world to sweep Earth's interior in many different directions and construct a three-dimensional image of what's inside.

strain

a change in location or displacement, orientation or rotation, shape or distortion

stress

as the force applied per units of area on the plane

pressure

acts on all sides of an object. Force magnitude over an area

compression

rock is being squeezed together

a mineral filled crack

vein

strike

The angle between an imaginary horizontal line on the plane and the direction to true north.

dip

The angle of the plane's slope or, more precisely, the angle between a horizontal plane and the dip line, as measured in a vertical plane perpendicular to the strike.

a horizontal plane has a dip of

0 degrees

vertical plane as a dip of

90 degrees

Dip slip Fault (Reverse Fault)

parallel the dip line

strike-slip fault

A fault on which the slip direction is parallel to a horizontal line on the fault surface.

normal fault

A type of fault where the hanging wall slides downward; caused by tension in the crust

reverse fault

if the hanging wall block slides up. can also be called a thrust fault

Anticline

A fold in rock that bends upward into an arch

Synclines

downward, troughlike folds

relative age

the age of a feature with respect in another sequence

numerical age (absolute)

age of a feature given in years

Uniformitarianism

A principle that geologic processes that occurred in the past can be explained by current geologic processes

cross-cutting relationships

if one geological feature cuts across the other, the feature being cut is older

Unconformity

A break in the geologic record created when rock layers are eroded or when sediment is not deposited for a long period of time. can represent a period of erosion

angular unconformity

rocks are tilted before unconformity happened

disconformity

A type of unconformity in which the beds above and below are parallel.

radioactive decay

the process in which a radioactive isotope tends to break down into a stable isotope of the same element or another element

parent atom

an atom of a radioactive isotope that has not yet decayed

daughter atom

the product atom from the radioactive decay of a parent atom