Weeks 1 & 2: Study Questions

Part I (continued): PLATE TECTONIC THEORY.

Example questions:

• Do most earthquakes occur in the middle or near the edges of tectonic plates?
• See the USGS Earthquake Activity page for recent earthquake locations.
• What are the three type of plate boundaries?

Here is a link to a page that has a great explanation of density, buoyancy, isostasy, and the structure of the Earth's interior from the University of Michigan. Scroll down and try out the density/buoyancy demo.

Part II. The composition of the Earth and its internal structure:

• What is the most abundant (in terms of weight %) element in the whole Earth?
• What is the most abundant (in terms of weight %) element in the Earth's crust?
• What are the compositional layers that make up the Earth?
• What are the mechanical layers inside the Earth?

<-- Click on this diagram for a closer view.

It is a generalized diagram that clearly shows the difference between COMPOSITIONAL and MECHANICAL layers within the Earth.

Answers to the practice questions above:

Earthquakes occur primarily (not exclusively) near the edges of tectonic plates.

The three types of plate boundaries are:

1. Divergent
2. Convergent
3. Transform

The most abundant element in the Earth (in terms of weight %) is Iron.

The most abundant element in the crust (in terms of weight %) is Oxygen.

See the diagram above for the compositional and mechanical layers inside the Earth.