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On a transmission inverse problem
In crosswell seismic experiments, seismic sources are fired in one well, and the wave-fields generated are measured in another well. The goal of the crosswell seismology is to find physical parameters, especially the ...
Imaging complex structures with semi-recursive Kirchoff migration
Attempting to image the subsurface in areas of complex geology and rapid lateral velocity variation is a challenging problem. In particular, using prestack Kirchhoff migration in conjunction with first arrival travel times ...
Three-dimensional first arrival traveltimes and amplitudes via eikonal and transport finite difference solvers
First arrival traveltimes and associated amplitudes are essential components in Kirchhoff migration and modeling. Traditionally they have been determined by ray tracing. However ray tracing does not give traveltimes on a ...
Modeling electromagnetic fields of the earth's magnetosphere
The early version of the Toffoletto - Hill - Ding open magnetosphere model is improved and generalized in this thesis. This model computes the interplanetary magnetic field (IMF) dependent magnetic and electric fields in ...
Broadening theories of soils genesis: Insights from Tanzania and simple models
Three basic assumptions of soil formation are challenged herein: the degree of chemical weathering decreases with depth; increased physical weathering due to high topographical gradients causes an increase in chemical ...