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MIGRATOM: Geophysical Tomography Using Wavefront Migration and Fuzzy Constraints.

PB94174448

Publication Date	1994
Personal Author	Jackson, M. J.; Tweeton, D. R.
Page Count	44
Abstract	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.
Keywords	Geophysical prospecting Computer aided tomography Imagery Fuzzy logic Mining Wave propagation Rocks Rock mechanics Ray tracing Windows(Computer programs) Tests
Source Agency	Bureau of Mines
NTIS Subject Category	48A - Mineral Industries 48F - Geology & Geophysics
Corporate Authors	Bureau of Mines, Minneapolis, MN. Twin Cities Research Center.
Document Type	Technical Report
Title Note	Rept. of investigations/1994.
NTIS Issue Number	199417

MIGRATOM: Geophysical Tomography Using Wavefront Migration and Fuzzy Constraints.

MIGRATOM: Geophysical Tomography Using Wavefront Migration and Fuzzy Constraints.
PB94174448

Publication Date	1994
Personal Author	Jackson, M. J.; Tweeton, D. R.
Page Count	44
Abstract	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.
Keywords	Geophysical prospecting Computer aided tomography Imagery Fuzzy logic Mining Wave propagation Rocks Rock mechanics Ray tracing Windows(Computer programs) Tests
Source Agency	Bureau of Mines
NTIS Subject Category	48A - Mineral Industries 48F - Geology & Geophysics
Corporate Authors	Bureau of Mines, Minneapolis, MN. Twin Cities Research Center.
Document Type	Technical Report
Title Note	Rept. of investigations/1994.
NTIS Issue Number	199417