Explore BrainMass

Layers of the Earth and Rocks and Minerals

I need help with the following questions:

1. On the layers of the earth (crust, upper mantle, lower mantle, outer core, and inner core), complete a short summary or list that describes the basic attributes of the layers listed.

2. In terms of rocks and minerals (minerals drag-drop, density of minerals, igneous rocks and silicates, and virtual rock lab), complete a short summary that explains the differences among your chosen types of rocks and minerals.

3. Limestone can be packed with fossils. So, given that information how would you classify limestone and why?

© BrainMass Inc. brainmass.com August 21, 2018, 5:53 am ad1c9bdddf

Solution Preview

1. The crust is the outer most layer of the earth and is also the thinnest, averaging about 5km under oceans and 30km thick under continents. The outer layer, or the crust, can be categorized into two subsections, the oceanic crust and the continental crust. The oceanic and continental crusts cumulatively are referred to as the lithosphere, due to its cool and rocky physical attributes and its chemical composition. The oceanic crust is only 0.099% of the earths mass and has a small depth. The ocean floor is covered in basalt, which originates from volcanic activity, indicating that an oceanic ridge system with many volcanoes may be responsible for developing the oceanic crust. The continental crust is the second smallest area of the earth, making up 0.374% of the earth's mass. This layer is composed of crystalline rocks made of low density buoyant minerals such as quartz, and feldspar.

The upper mantle composes 15.3% of the total mantle-crust mass and is composed of crystalline forms of olivine, and pyroxene. These compounds are abundant in magnesium, iron, and silica. The upper mantle makes up 10% of the earth's mass, and is relatively large when compared to interior layers. This layer is dominantly made of solid minerals but the asthenosphere could be partly liquid molten.

The lower mantle has a chemical composition composed of silicon, magnesium, and oxygen and is also believed to contain some iron, calcium and aluminum. This layer is ...

Solution Summary

The layers of the earth, ricks and minerals are examined.