NSW Prelim EES Mod 1-4

accretion

A process in which masses in a protoplanetary disc attract particles by gravitational attraction

outgassing

The release of gases that were dissolved, trapped, frozen or absorbed in some material. For example, when a volcano erupts, releasing trapped gasses

seismic

_______________ waves (earthquake waves) produced by sudden Earth movements

primary

_________________ waves are the fastest seismic waves. They are compression waves that can pass through solids and liquids.

secondary

_________________ waves are the 2nd fastest seismic waves. They are transverse waves that cannot pass through liquids.

meteorites

A lump of rock or metal from space that reaches the surface of the earth without being completely vaporised

crust

A thin, hard outer coating, such as the hard outer surface of the earth

oceanic

_______________________ crust is thin crust made of basalt and other rocks higher density rocks

density

Mass per unit volume of a substance

gravity

The force of attraction between two masses

continental

_______________________ crust is thick crust made of granite and other rocks lower density rocks

mantle

A layer in the earth between the crust and the core and made of rock that is nearly solid but allows slow movements of the crust

outer core

The layer of the earth composed of liquid iron and nickel that lies below its mantle.

inner core

The solid central part of the Earth

lithosphere

Rigid crust and upper mantle of the earth

asthenosphere

That part of the upper mantle beneath the rigid lithosphere that is plastic enough for rock flow to occur

geologic time

The huge period of time over which Earth's rocks have formed

uniformitarianism

The idea that geological processes have occurred in the same regular manner and intensity throughout geological time

unconformity

A boundary between two rock strata of different ages, indicating that erosion occurred before the upper layer was deposited

radiation

The process of giving off radiant energy in the form of waves or particles

radioactive

The giving off of alpha particles, beta particles and gamma waves as an isotope forms a new isotope is called _______________________ decay

half-life

The time it takes for half a sample of radioactive atoms to decay

isotope

Atoms of the same element that have different numbers of neutrons

mineral

A crystalline solid with a definite composition that occurs in the rocks of the earth's crust

mafic

Dark coloured igneous rocks due to high concentrations of ferromagnesian minerals are called __________________ rocks

felsic

Light coloured igneous rocks with relatively large amounts of feldspars and quartz are called __________________ rocks

hardness

A measure of how easily a mineral can be scratched

streak

The color of the powder of a mineral

lustre

Description of how light reflects off the surface of a mineral

specific

The mass of a mineral divided by its volume is called its density or ________________ gravity

cleavage

The tendency of a mineral to break along flat surfaces

Moh's

A set of minerals used as standards for testing mineral hardness is ______________ hardness scale

rock

Made from a mixture of minerals

igneous

A type of rock that forms from the cooling of molten rock at or below the surface.

texture

The size of minerals in an igneous rock or a soil is called ___________________

sedimentary

Rocks formed from sediments compacted and cemented together

strata

The layers within sedimentary rocks

superposition

The law of _________________________states that the top rock layer and its fossils are youngest and the bottom are oldest.

clastic

Rocks formed from the weathered and eroded pieces of other rocks are called _______________ sedimentary rocks

precipitation

Chemical sedimentary rocks are formed by
chemical ______________________ or biological activity

organic

material derived from living organisms

inorganic

Not formed from living things or the remains of living things

metamorphic

___________________________ rocks form when other rocks are subjected to heat and/or pressure

contact

Rocks altered by heat from nearby magma are called _________________ metamorphic rocks

regional

Rocks altered primarily by pressure over a large area are called _________________ metamorphic rocks

foliations

Metamorphic minerals that are flaky (aligned in parallel structures) are called _______________________

horizon

Any layer within the soil

climate

The average weather conditions in an area over a long period of time

topography

refers to the shape and elevation of land in a region

leaching

removal of dissolved materials from soil by water moving downwards

pH

Scale for measuring the strength of different acids and bases

stratigraphy

the study of rock layers and the sequence of events they reflect

anticline

a fold formed by upfolding or arching of
rock layers

syncline

A fold in rock that bends downward to form a V shape

dyke

An igneous intrusion across rock layers

sill

An igneous intrusion between rock layers

inclusion

A body or particle of different composition embedded within igneous rock

correlation

Matching the ages of rocks and fossils from separate locations

relative

____________________ dating is describing how old something is by comparing it to something else

absolute

____________________ dating is describing how old something is in years

index

_________________ fossils are useful for dating the strata in which they are found.

resources

Materials found in the earth that people need and value

renewable

Resources that can be replaced at the same rate at which they are consumed

non-renewable

Resources that cannot be replaced once they are consumed

reserve

The known quantity of a resource that can be economically recovered

deposit

A natural concentration of minerals in the earth's crust is a mineral ___________________

ore

A rock containing a high enough concentration of a useful mineral to make it economic to mine

mining

the act of extracting ores or coal etc from the earth

hydrothermal

________________________ mineral deposits form in association with magma and water

segregation

Magmatic ___________________ is when minerals crystallize and sink to the bottom of a cooling magma chamber, with different minerals deposited at different temperatures

hot spot

A mantle plume where rising magma can reach the surface, especially away from the edge of crustal plates

pegmatite

A coarse-grained igneous rock with interlocking crystals often rich in feldspars, micas and quartz

vein

a narrow deposit of a mineral that is sharply different from the surrounding rock

evaporites

Minerals precipitated from the water in closed lakes or seas as they dry up

fossil fuels

Any fuels that formed from the decayed remains of ancient plants and animals

coal

A solid fossil fuel formed underground from buried, decomposed plant material.

seam

A layer of coal usually thick enough to be profitably mined

coal seam gas

A form of natural gas (mainly methane) extracted from coal beds

rock core

A vertical, cylindrical-shaped boring used to determine composition and stratification of rocks underground.

geophysical

The scientific study of the physical characteristics of the Earth uses _____________________________ techniques

remote sensing

processes that collect data from the Earth at a distance

drilling

the act of boring a hole in the earth in the hope of producing resources

overburden

Layer of soil and rock overlying a mineral deposit

open pit

Mine in which ore is exposed at the surface in a large excavation.

fracking

Pumping of high pressure water to break rocks and release natural gas

plate tectonics

theory that Earth's surface is made of huge sections that move with respect to each other

plates

The sections that the lithosphere are broken into.

palaeoclimate

A climate existing at a particular time in the geological past.

magnetic reversal

When Earth's magnetic field changes polarity from normal to reversed.

mid-oceanic ridge

An underwater mountain range formed when tectonic plates diverge and magma rises.

Wegener

Alfred ____________________ proposed the continental drift theory

continental drift

Wegener's hypothesis that the continents slowly moved over Earth's surface

Holmes

Arthur ___________________ was the geologist who first proposed that convection currents in the mantle where driving plate movements

Hess

Harry ______________ pioneered early sea floor mapping and proposed sea floor spreading

convergent

A _________________ boundary occurs when two tectonic plates collide into each other.

subduction

process in which two plates collide and the denser ocean plate descends below the other

trench

extremely deep areas in the ocean that are created by a subducting plate

earthquake

Vibrations produced when rocks break along a fault

island arc

a chain of volcanic islands formed at an ocean-ocean convergent boundary

focus

The point beneath Earth's surface where rock breaks under stress and causes an earthquake