Chapter 11 Vocab

Question 1

Ancestral Rockies

Answer 1

The late Paleozoic uplifts of the Rocky Mountain region; they eroded away long before the present Rocky Mountains formed.

Question 2

Archean Eon

Answer 2

The middle Precambrian Eon.

Question 3

Banded iron formation (BIF)

Answer 3

Iron-rich sedimentary layers consisting of alternating gray beds of iron oxide and red beds of iron-rich chert.

Question 4

Basin and Range Province

Answer 4

A broad, Cenozoic continental rift that has affected a portion of the western United States in Nevada, Utah, and Arizona; in this province, tilted fault blocks form ranges, and alluvium-filled valleys are basins.

Question 5

Cambrian explosion

Answer 5

The remarkable diversification of life, indicated by the fossil record, that occurred at the beginning of the Cambrian Period.

Question 6

Craton

Answer 6

A long-lived block of durable continental crust commonly found in the stable interior of a continent.

Question 7

Cratonic platform

Answer 7

A province in the interior of a continent in which Phanerozoic strata bury most of the underlying Precambrian rock.

Question 8

Epicontinental sea

Answer 8

Shallow sea overlying a continent.

Question 9

Exotic terrane

Answer 9

A block of land that collided with a continent along a convergent margin and attached to the continent; the term exotic implies that the land was not originally part of the continent to which it is now attached.

Question 10

Gondwana

Answer 10

A supercontinent that consisted of today’s South America, Africa, Antarctica, India, and Australia. Also called Gondwanaland.

Question 11

Hadean Eon

Answer 11

The oldest of the Precambrian eons; the time between Earth’s origin and the formation of the first rocks that have been preserved.

Question 12

Laramide orogeny

Answer 12

The mountain-building event that lasted from about 80 Ma to 40 Ma, in western North America; in the United States, it formed the Rocky Mountains as a result of basement uplift and the warping of the younger overlying strata into large monoclines.

Question 13

Laurentia

Answer 13

A continent in the early Paleozoic Era composed of today’s North America and Greenland.

Question 14

Pangaea

Answer 14

A supercontinent that assembled at the end of the Paleozoic Era.

Question 15

Phanerozoic Eon

Answer 15

The most recent eon, an interval of time from 542 Ma to the present.

Question 16

Pleistocene Ice Age

Answer 16

The period of time from about 2 Ma to 14,000 years ago, during which the Earth experienced an ice age.

Question 17

Proterozoic Eon

Answer 17

The most recent of the Precambrian eons.

Question 18

Rodinia

Answer 18

A proposed Precambrian supercontinent that existed around 1 billion years ago.

Question 19

Shield

Answer 19

An older, interior region of a continent.

Question 20

Superplume

Answer 20

A huge mantle plume.

Question 21

Stromatolite

Answer 21

Layered mounds of sediment formed by cyanobacteria; cyanobacteria secrete a mucous-like substance to which sediment sticks, and as each layer of cyanobacteria gets buried by sediment, it colonizes the surface of the new sediment, building a mound upward.