Global seismic tomography and modern parallel computers

A fast technological progress is providing seismic tomographers with computers
of rapidly increasing speed and RAM, that are not always properly taken
advantage of. Large computers with both shared-memory and distributedmemory
architectures have made it possible to approach the tomographic
inverse problem more accurately. For example, resolution can be quantified
from the resolution matrix rather than checkerboard tests; the covariance
matrix can be calculated to evaluate the propagation of errors from data to
model parameters; the L-curve method can be applied to determine a range
of acceptable regularization schemes. We show how these exercises can be
implemented efficiently on different hardware architectures.

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