MIGRATOM: geophysical tomography using wavefront migration and fuzzy constraints.
Jackson MJ; Tweeton DR
Minneapolis, MN: U.S. Department of the Interior, Bureau of Mines, RI 9497, 1994 Jan; :1-25
MIGRATOM is a third-generation PC-based computer program for geophysical tomograph. It was developed to enable users to address a variety of mining-related problems by mathematically reconstructing the distribution of physical properties in a rock mass, using measurements of travel time or amplitude of wave energy propagated through the rock mass. Examples of applications include litho-logic characterization, fracture detection, fluid monitoring, stress evaluation, and blast assessment. The resolution and accuracy of tomographic reconstructions generally depend very strongly on the geometry of source and receiver locations. In many practical applications, such as cross-borehole tomography, limited coverage results in nonunique reconstructions. MIGRATOM allows the user to constrain the inversion, in order to reduce the nonuniqueness problem. A new approach to application of constraints implemented in MIGRATOM is based on fuzzy logic techniques. Refraction of wave energy is modeled in MIGRATOM using an approach based on Huygens' Principle. Propagation of a continuous wavefront is modeled as a constructive interference phenomenon, which obviates the shadow-zone problem that affects conventional ray-tracing calculations.
Imagery; Fuzzy-logic; Mining; Wave-propagation; Rocks; Rock-mechanics; Ray-tracing; Computer-programs; Tests; Geophysical-prospecting; Computer-aided-tomography
Report of Investigations
NTIS Accession No.
Minneapolis, MN: U.S. Department of the Interior, Bureau of Mines, RI 9497