The Standard Method Used to Divide Earth's Long Natural History Into Manageable Parts

What is the main criterion that scientists use to decide where to place the boundaries between the major divisions of the geologic time scale?

• major changes in the structure of Earth's layers

• major changes that occur in the solar system

• major changes in the arrangement of the continents

• major changes that are recorded in the rock and fossil record

Tags

NGSS.MS-ESS1-4

Which is NOT an accurate statement about the geologic time scale?

• The geologic time scale is unchanging

• Evidence from rocks and fossils has informed the geologic time scale.

• We have less evidence of Earth's early history because of rock changes over time.

• The history of Earth is long and the geologic time scale breaks it into manageable parts.

Tags

NGSS.MS-ESS1-4

What proportion of the geological time scale is classified as Precambrian time?

• over 80%

• 50%

• 20%

• under 10%

Tags

NGSS.MS-ESS1-4

Which example shows that not all geologic change occurs slowly?

• meteorite impact

• tectonic plate motion

• widespread glaciation

• weathering and erosion

Tags

NGSS.MS-ESS2-2

Which statement is NOT accurate regarding the changes in Earth's surface over time?

• The tectonic plates of Earth can move

• Now that the Earth has been shaped by geological processes, it will not be reshaped.

• The landforms we see today, such as mountains and canyons, formed over millions of years.

• Sedimentary rock formation took place in the past, and sedimentary rock continues to be formed today.

Tags

NGSS.MS-ESS1-4

NGSS.MS-ESS2-2

NGSS.MS-ESS2-3

In the rock layers of a prairie environment, a fossil of an extinct species of shark is found. Many layers below also contain water-dwelling organisms, but no fossils of sharks or other aquatic animals are found in the layers above the rock layer where the shark was found. Which statement is NOT a conclusion that can be made from the shark fossil discovery?

• The area was once covered by water.

• The layers below the shark fossil are older than the layers above the shark fossil.

• The relative age of the shark fossils cannot be determined since the shark fossils do not appear in all of the rock layers.

• The disappearance of the shark fossils and other aquatic animals from the fossil record indicates an environmental change.

Tags

NGSS.MS-ESS1-4

NGSS.MS-LS4-1

A layer of volcanic ash is found between two other rock layers. Absolute dating shows that the ash is about 65 million years old. Which conclusion can be made from these three rock layers?

• The top layer is also about 65 million years old.

• The bottom layer is also about 65 million years old.

• The top layer is less than 65 million years old.

• The bottom layer is less than 65 million years old.

Tags

NGSS.MS-ESS1-4