Geologic Time

Question 1

sediment

Answer 1

Solid particles such as weathered rock fragments, materials from organisms, or minerals that settle out of a solution that are deposited at or near Earth’s surface

Question 2

fossil

Answer 2

the trace of an organism from the past

Question 3

geologic timescale

Answer 3

the standard method used to divide Earth’s long natural history into manageable parts

Question 4

tectonic plates

Answer 4

blocks of lithosphere that consist of the crust and the rigid outermost part of the mantle

Question 5

strata

Answer 5

a layer or a series of layers of rock in the ground.

Question 6

faunal succession

Answer 6

the combination of fossils changes vertically from layer to layer and the groupings of fossils as well as the order of combinations are mostly consistent from place to place.

Question 7

index fossil

Answer 7

a fossil that is useful for dating and correlating the strata in which it is found.

Question 8

Cambrian explosion

Answer 8

the time about 540 million years ago when revolutionary changes in life forms in Earth’s history started