fossil record

Question 1

uniformitarianism

Answer 1

The theory that changes in the earth’s crust during geological history have resulted from the action of continuous and uniform processes.

Question 2

Catastrophism

Answer 2

The theory that changes in the earth’s crust during geological history have resulted chiefly from sudden violent and unusual events.

Question 3

paleontology

Answer 3

The branch of science concerned with fossil animals and plants.

Question 4

relative dating

Answer 4

the process of determining if one rock or geologic event is older or younger than another, without knowing their specific ages—i.e., how many years ago the object was formed.

Question 5

absolute dating

Answer 5

The process of determining an age on a specified chronology in archaeology and geology.

Question 6

superposition

Answer 6

any sequence of layered rocks, a given bed must be older than any bed on top of it.

Question 7

isotope

Answer 7

Isotopes are variants of a particular chemical element which differ in neutron number, and consequently in nucleon number.

Question 8

radioactive decay

Answer 8

the process by which an unstable atomic nucleus loses energy by radiation.

Question 9

half-life

Answer 9

the time taken for the radioactivity of a specified isotope to fall to half its original value.

Question 10

fossil

Answer 10

the remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock.

Question 11

trace fossil

Answer 11

a fossil of a footprint, trail, burrow, or other trace of an animal rather than of the animal itself.

Question 12

mold

Answer 12

Mold is a type of fungus that grows indoors and outdoors. It thrives in moist, warm conditions

Question 13

cast

Answer 13

when an animal, plant, or other organism dies, its flesh decays and bones deteriorate due to chemical reactions; minerals gradually enter into the cavity, resulting in a cast

Question 14

unconformity

Answer 14

a surface of contact between two groups of unconformable strata.

Question 15

mass extinction

Answer 15

A mass extinction is usually defined as a loss of about three quarters of all species in existence across the entire Earth over a “short” geological period of time.

Question 16

Jurassic period

Answer 16

The Jurassic is a geologic period and system that spanned 56 million years from the end of the Triassic Period 201.3 million years ago to the beginning of the Cretaceous Period 145 Mya.

Question 17

Cretaceous period

Answer 17

The Cretaceous is defined as the period between 145.5 and 65.5 million years ago,* the last period of the Mesozoic Era, following the Jurassic and ending with the extinction of the dinosaurs (except birds).

Question 18

Devonian period

Answer 18

The Devonian, part of the Paleozoic era, is otherwise known as the Age of Fishes, as it spawned a remarkable variety of fish.

Question 19

Quaternary period

Answer 19

The Quaternary Period is famous for the many cycles of glacial growth and retreat, the extinction of many species of large mammals and birds, and the spread of humans.

Question 20

Permian period

Answer 20

The Permian period, which ended in the largest mass extinction the Earth has ever known, began about 299 million years ago. The emerging supercontinent of Pangaea presented severe extremes of climate and environment due to its vast size.