DETERMINATION OF ANISOTROPY HTI BY SEISMIC INVERSION USING GENETIC ALGORITHM IN THE VALLE MEDIO OF MAGDALENA BASIN
Published 2016-10-31
Keywords
- HTI anisotropy,
- seismic inversion,
- genetic algorithm
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Abstract
A genetic algorithm was implemented in MATLAB to perform seismic inversion and determine HTI anisotropy, which was applied to a seismic project in the Middle Magdalena Valley basin in Colombia. The algorithm, which includes the concept of migration of populations (MP), was tested in an isotropic condition (parallel to the fractures), and in a condition of anisotropy (perpendicular to fractures), showing better performance in the testing phase with real data. The presence of weak anisotropy is determined in the study area with associated fractures oriented in azimuth of 45 °, being perpendicular to the current stress regime. This result would explain the weak anisotropy related to fractures associated with a paleo-stress regime.
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References
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