Abstract:
A major question that is present today in Geosciences deals with the mechanism of plate movement. The idea of plate tectonics, developed in the 1960’s, set forth the basic framework of plate movement but left many questions. In my seminar I wish to focus on the North American plate, and the dynamics of its movement. There are two basic hypotheses or models of movement that are being investigated. The first of these two models proposes that convecting mantle in contact with the base of the North American craton is moving the continent. The second model of motion deals with thermal evolution of the oceanic lithosphere which results in ridge push forces. The validity of these two models has been investigated through the interpretation of deformation within the North American plate.
Fig. 1 Cross section of Earth showing dynamic
processes involved in plate tectonics from http://www.solarviews.com/eng/earthint.htm
Fig. 2 Diagram A depicts a cartoon of the roots of the North
American continent that is being moved by ridge push forces, and diagram B
depicts the continent being moved by convective flow (Bokelmann, 2002).
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