Review for Geologic Time Test

When do scientists believe that life first appeared on Earth?

• 100 million years ago

• 400 million years ago

• 3.8 billion years ago

• 4.6 billion years ago

Which of the following most often happens when individuals of a species become isolated from other members of the species?

• They become extinct

• The species finds a new home

• The species becomes two separate species

• The animals remain the same - no change

Which type of event might cause a dramatic change in the history of life on Earth?

• flood

• earthquake

• asteroid crash

• snow storm

Which of the following is an example of an environmental condition that directly contributes to species extinction?

• new humans in the area

• loss of habitat

• flood and raining

• snow storm

Which description below demonstrates why a volcanic eruption or the impact of an asteroid or large meteor would cause a mass extinction?

• Both events cause air pollution

• Both events would cause other natural disasters to occur.

• Both events would cause debris to enter the Earth's atmosphere and cause a major change in climate.

• Both events would cause an extinction upon impact or eruption.

Geologists are conducting a study on many layers of different types of rock in the Grand Canyon. These geologists will likely find ancient fossils that reveal the history of life near the Grand Canyon in

• igneous rock layers

• layers of sedimentary rock

• . layers of volcanic rock.

• . metamorphic rock layers

Geologists studying the history of Earth obtain evidence of past ice ages from the movements of large glaciers. Evidence from these glacier movements is seen in

• ancient cave writings

• changes in the amount of CO2 in the atmosphere

• layers of sedimentary rock

• the fossils of plants and animals

Geologists obtain evidence of changes in the history of Earth's surface conditions from layers of rock because

• older layers of sedimentary rock form on top of younger layers.

• younger layers of sedimentary rock form on top of older layers.

• younger layers of igneous rock form on top of older layers.

• older layers of igneous rock form on top of younger layers.

Compaction occurs when deeply buried rock pieces are forced together by pressure. Compaction is involved in which of the following geological processes?

• igneous rock uplift

• sedimentary rock formation

• igneous rock erosion

• metamorphic rock weathering

Heat from Earth's core causes chemical and mineral changes which turns sedimentary rock grains into solid sedimentary rock layers. This process is known as

• erosion

• transportation

• cementation

• deposition