A Simple Model to Predicting Pore Pressure from Shear Wave Sensitivity Analysis

摘要

A successful seismicity alongside core analysis provides data for subsurface structural mapping, definition of lithology, identification of the productive zones, description of their depths and thickness. Inadequate understanding of Pore pressure of a formation is regarded as one of the major problems drillers face in the exploration area. This may be amongst others, the pressure acting on the fluids in the pore spaces of the rock. Pore pressure can be normal, abnormal or subnormal. Shear waves is a secondary wave that travels normal to the direction of propagation. Shear waves are slow and thus, get to the surface after primary wave. It is with this intrinsic property that this project was initiated and researched. Data was obtained from a major operator in Niger Delta. Methods of this study are as follows: log description, interpretation and analysis and evaluation of pore pressure using the petro-physical parameters, model development using Domenico'sequation as foundation and the shear wave velocity estimation. The result from this study, shows the importance of well logs and shear wave velocity in the evaluation of pore pressure, it also indicates where pressure can be encountered during drilling activities.