Reflection seismic techniques locate geopressured geothermal anomalies

The prediction log (P-log) has been used worldwide as a best-efforts prediction of the lithology and pressures to be encountered while drilling deep exploration tests. In these endeavors, it has been observed that high temperatures are a common characteristic of zones of abnormal pressure. A linear relationship between quantitative amounts of pressure and heat has not been established, but a good correlation exists for relative quantities. This is especially true of the Anadarko Basin and the Gulf of Mexico embayment areas of Texas and Louisiana. The phenomena have been noted in these areas for decades in the course of drilling deep tests. In the past few years, some geophysicists have begun to extract from seismic data information that locates and delineates these anomalous conditions. The interpretive techniques outlined in this presentation have been used all over the world, with outstanding results in predicting abnormal pressure and relative lithology. The benefits are incalculable for lease evaluation, logistics planning, better drilling programs, and environmental protection. With the current sudden demand for more geothermal energy, it is obvious that these same techniques have direct appliqation to the exploration for geopressured geothermal anomalies. The method should become a very powerful tool in helping to solve out energy problems. (10 figs., 3 refs.