Plate tectonics   Knowns and unknowns
Channel: Paul Wessel
Date: 2020-02-05

Dr. David Sandwell (Scripps Institution of Oceanography, UCSD) gave a guest lecture via Skype in Fall 2008 for a graduate class on Advanced Plate Tectonics in SOEST, University of Hawaii at Manoa.  The students recorded the lecture and produced video podcasts of the event.  This is one of 8 such lectures from the course which was taught by Prof. Paul Wessel.

ABSTRACT:

"Knowns - Plate Tectonic theory developed during the 60’s and 70’s provides a clear understanding of spreading ridges, transform faults, and subduction zones.  Satellite altimeter measurements of the marine gravity field imaged these structures globally providing a strong confirmation of the theory as well as aiding in the development of global maps of seafloor age, seafloor roughness, and seamount distributions.

Unknowns – While the basic theory is well understood there are two areas that remain controversial.  The first is the origin of hotspot volcanic chains. The second is the origin of Haxby gravity lineations.  I will discuss the role of satellite gravity in addressing these controversies."