| 摘要 |
FIELD: physics.SUBSTANCE: group of inventions includes a method of extracting hydrocarbons from a subsurface region, a method of transforming seismic data paths and a method of determining a near-surface earth model of elastic shear wave propagation velocity based on the seismic data path. The invention employs seismic data, recorded preferably with a plurality of sources and receivers and a two-stage inversion technique. First, variations in surface-wave signals are decomposed (303) into surface-consistent transfer functions, preferably for each source, each receiver and each small region (301) of the surface. The transfer functions for each region are then inverted (308) to determine soil properties or near-surface properties (such as the shear modulus) as a function of depth. The method can solve for the complex multi-mode nature of the surface waves for media with vertical and lateral changes in properties.EFFECT: avoiding errors and limits in resolution for traditional methods from misidentification of ground roll modes or from assuming laterally uniform soil properties, obtaining elastic soil properties, obtaining elastic properties as a function of depth from surface or depth profile of properties.22 cl, 15 dwg |
