| 摘要 |
A method of generating a two-dimensional pore pressure gradient and fracture gradient cross section from seismic survey data is disclosed. In general, the method includes generation of a two-dimensional overburden gradient cross section and a two-dimensional normal compaction trend line cross section. The two-dimensional overburden gradient and normal compaction trend line cross sections are preferably generated by extrapolating the overburden gradient and normal compaction trend lines at an existing offset well, after correlating seismic interval transit times to the density and well log data at the offset well location. Once the two-dimensional overburden gradient cross section and two-dimensional normal compaction trend line cross section are generated, the Eaton method is applied at each of the common depth points of interest to produce a two-dimensional pore pressure gradient cross section, at least at certain common depth points of interest. Poisson's ratio for rocks can also be applied to the pore pressure gradients, to produce a two-dimensional fracture gradient cross section. Accurate pore pressure and fracture gradient information at locations away from existing offset wells can thus be generated.
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