How Do We Know about Layers Deep within Earth?
ES0402  Beneath the Surface

This model shows mantle tomography beneath South America. The blue color represents areas where seismic waves travel faster than average, indicating rocks that are cooler or denser than average.

  !   After the 3-D model loads, click the arrow buttons to view it from different perspectives.
Paul Morin, University of Minnesota with data from
E.R. Engdahl, R.D. Van der Hilst and R. P. Buland
3-D seismic tomography model for South America. Blue areas show where seismic waves travel faster than average.

11. What does this tomographic model indicate about the underlying structure?

 


	

 	

		
			
	

	
	

		 
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