Geology

Front 1

asthenosphere

Back 1

the part of the mantle that lies below the lithosphere; behaves plastically and flows

Front 2

Big Bang

Back 2

a model for the evolution of the universe in which a dense, hot state was followed by expansion, cooling, and a less dense state

Front 3

core

Back 3

the interior part of the Earth, beginning at a depth of about 2900 km; probably composed mostly of iron and nickel; divided into an outer liquid core and a solid inner core

Front 4

crust

Back 4

Earth's outermost layer; the upper part of the lithosphere, which is separated from the mantle by the Moho; divided into continental and oceanic crust

Front 5

geologic time scale

Back 5

a chart with the designation for the earliest interval of geologic time at the bottom, followed upward by dsignations for progressively more recent time intervals

Front 6

geology

Back 6

the science concerned with the study of Earth; includes studies of Earth materials (minerals and rocks), surface and internal processes, and Earth history

Front 7

hypothesis

Back 7

a provisional explanation for observations; subject to continual testing and modification, if well supported by evidence, hypotheses are generally called theories

Front 8

igneous rock

Back 8

any rock formed by cooling and crystallization of magma or by the accumulation and consolidation of pyroclastic materials

Front 9

Jovian planets

Back 9

any of the four planets (Jupiter, Saturn, Uranus, Neptune) that resemble Jupiter, all are large and have low mean densities, indicating they are composed mostly of lightweight gases, such as hydrogen and helium, and frozen compounds, such as ammonia and methane

Front 10

lithosphere

Back 10

Earth's outer rigid part consisting of the upper mantle, oceanic crust, and continental crust

Front 11

mantle

Back 11

the thick layer between Earth's crust and core

Front 12

metamorphic rock

Back 12

any rock altered by high temperature and pressure and the chemical activities f fluids is said to have been metamorphosed (slate, gneiss, and marble)

Front 13

mineral

Back 13

a naturally occurring, inorganic crystalline solid that has characteristic physical properties and a narrowly defined chemical composition

Front 14

plate

Back 14

an individidual segment of lithosphere that moves over the asthenosphere

Front 15

plate tectonic theory

Back 15

the theory that large segments of the outer part of Earth (lithospheric plates) move relative to one another

Front 16

principle of uniformitarianism

Back 16

a principle holding that we can interpret past events by understanding present-day processes; based on the assumption that natural laes have not changed through time

Front 17

rock

Back 17

an aggregate of one or more minerals, as in limestone or granite, or fragments, as in conglomerate; includes rocklike materials such as coal and natural glass

Front 18

rock cycle

Back 18

a group of processes through which Earth materials may pass as they are transformed from one rock type to another

Front 19

scientific method

Back 19

a logical, orderly approach that involves gathering data, formulating and testing hypotheses, and proposing theories

Front 20

sedimentary rock

Back 20

any rock composed of sediment (sandstone, limestone)

Front 21

solar nebula theory

Back 21

a theory for the evolution of the solar system from a rotating cloud of gas

Front 22

system

Back 22

a combination of related parts that interact in an organized fashion. Earth's systems include the atmosphere, hydroshpere, biosphere, and solid Earth

Front 23

terrestrial planet

Back 23

any of the four innermost planets (Mercury, Venus, Earth, Mars), they are all small and have high mean densities indicating they are composed of rck and metallic elements

Front 24

theory

Back 24

an explanation for some natural phenomenon that has a large body of supporting evidence, to be considered scientific, it must be testable