Microlocal analysis of borehole seismic data

Borehole seismic data is obtained by receivers located in a well, with sources on the surface or another well. Using microlocal analysis, we study possible approximate reconstruction, via linearized, filtered backprojection, of an isotropic sound speed subsurface for three types sets. The may form dense array surface, be along line (walkaway geometry) borehole (crosswell). We show that array, reconstruction feasible, no artifacts absence caustics background ray geometry, and mild presence fold sense define. In contrast, walkaway crosswell sets both give rise to strong, nonremovable artifacts.