Mantle circulation models with variational data assimilation: Inferring
past mantle flow and structure from plate motion histories and seismic
tomography

by Hans-Peter Bunge
Department of Geosciences
Princeton University

3-4pm
Friday Mar 7, 2003
Refreshments served at 2:45pm
Munk Conference Room
Cecil and Ida M. Green Institute of Geophysics and Planetary Physics
Scripps Institution of Oceanography
University of California, San Diego
http://mahi.ucsd.edu/seminar/

Abstract

In this talk I will attempt to explore a numerical framework to
reconstruct the internal structure of the Earth back into the recent
geologic past. The approach is just beginning to become feasible due to
rapid advances on three related fronts: 1) well-known inverse formalisms
(history matching) based on a numerical adjoint to the forward problem
of mantle convection, 2) increasingly realistic images of the internal
heterogeneity structure of the Earth, 3) rapid growth in computational
power, aided in recent years primarily by cost-efficient Beowulf
clusters. I will present two highly idealized synthetic examples to show
how we could attempt to restore Earth's mantle back into the Cretaceous
geologic period some 100 million years ago if the present-day Earth
structure was well known. I will discuss some geologic significance of the
result, which includes continental landscape evolution and implications
for the magnetic reversal behavior of the Earth's core.