There are a lot of tedious steps, but once finished it is fairly simple:
Plate tectonics is a unifying framework for understanding the dynamic geology of the Earth. The theory posits that the outermost layers of the Earth (the crust and uppermost mantle) make up the brittle lithosphere of the Earth. The lithosphere is broken up into a number of thin plates, which move on top of the asthenosphere (middle mantle). The asthenosphere is solid, but flows plastically over geologic time scales. Plate interiors are relatively stable, and most of the tectonic action (earthquakes, volcanism) takes place where plates meet – where they collide at convergent boundaries, move away from one another at divergent boundaries, or slide past one another at transform boundaries.
Reconstructions of the Earth's tectonic plate locations through time are available, for example, at:
http://www.scotese.com/newpage13.htm (Links to an external site.)
http://www.ucmp.berkeley.edu/geology/tectonics.html (Links to an external site.)
But how do we define plates and plate boundaries? On what are plate reconstructions and animations based? How do we know plates are moving, how can we track their positions in the past, and how can we predict their positions in the future?
To answer these questions, this assignment guides you through an examination of patterns on Earth – the topography of the earth's surface above sea level, the bathymetry of the ocean floor below sea level, and the distribution of earthquakes and volcanic rock ages. These patterns reveal plate boundaries, just as they did for geologists first developing plate tectonic theory in the 1960s. You'll then use geologic data to determine long-term average plate motions, to predict how our dynamic planet will change in the future.
To do this, you'll use the program Google Earth, and Google Earth layers compiled from various sources.
A. Getting started with Google Earth
On your computer, install the latest version of Google Earth Pro from https://www.google.com/earth/versions/ (Links to an external site.)
Once installed, open Google Earth, under the Tools/Options/3D View/ menu on a PC, or under the Preferences/3D View menu on a Mac, choose the "Decimal Degrees" and "Meters Kilometers" options and makes sure the "Use High Quality Terrain" box is checked.
Open the View menu. Go ahead and experiment with the options, but in general you should just have the Tool Bar, Side Bar and Status Bar checked. Also, on the View menu, hover over Navigation and you will see several options for the compass arrow and slide bars in the upper right corner of the Google Earth screen. "Automatically" is a good choice as it leaves a ghost of the image visible until you hover over it.
Load the DynamicEarth.kmz file from into Google Earth Pro. It is located at https://serc.carleton.edu/sp/library/google_earth/examples/49004.html (Links to an external site.) and is the top file in the "Description and Teaching Materials" list. You should be able to double-click on the filename and it will open. Or, you can download the file onto your computer first, and then open it in Google Earth Pro by using File/Open and navigating to the file.