Question

multiple choice 2 points
which of the following does not correctly describe earths continental crust?
it is denser than oceanic crust
it has the highest abundance of feldspar, quartz, and pyroxene minerals
granite is common in continental crust
it is composed of light - colored materials
multiple choice 2 points
which of the following is the coarsest (longest) division used in the geologic time scale?
era
eon
epoch
period

Explanation:

For question 2:

• Continental crust is less dense than oceanic crust. Oceanic crust is made of basalt (density about \(3.0\ g/cm^{3}\)), while continental crust is made of granite (density about \(2.7\ g/cm^{3}\)).
• Continental crust has a high abundance of feldspar, quartz, and pyroxene. Granite is a common rock in continental crust. It is composed of light - colored materials.

For question 3:

• In the Geologic Time Scale, the order from longest to shortest is eon > era > period > epoch.

Answer:

1. A. it is denser than oceanic crust
2. B. eon