Pore pressure prediction using 3D seismic velocity data: a case study, a carbonate oil field, SW Iran
Nosrat, E., Javaherian, A., Torabi, M.R. and Asiri, A.B., 2010. Pore pressure prediction using 3D seismic velocity data: a case study, a carbonate oil field, SW Iran. Journal of Seismic Exploration, 19: 141-159. Pore pressure is an important parameter in hydrocarbon resource exploration and production. Accurate knowledge of the pore pressure is a key requirement for safe and economical planning of wells. Knowledge of formation pressure is not only essential for safe and cost-effective drilling of wells, but also is critical for assessing exploration risk factors including the migration of formation fluids and seal integrity. Pore pressure prediction based on seismic velocity is a common method for pre-drill pore pressure prediction, especially in sandstone reservoirs. In this method, pore pressure can be obtained from transformation of seismic velocity to pore pressure. But seismic velocities need to be derived using methods having sufficient resolution for well planning purposes. In this study, the velocity derived from pre-stack time migration (PSTM) was available in some parts of the field; however, in another part of the field the only available velocity field was the stacking velocity. This combined velocity field was calibrated with the velocities derived from sonic logs. They were then sorted on regular grid sizes using some geostatistical methods. The effective pressure cube was constructed using the Bowers equation and the calibrated velocity field. The pore pressure cube was constructed by computing the differences between the overburden pressure cube and the effective pressure cube, which was computed using the density cube. Finally the predicted pore pressure cube was calibrated with the measured pore pressures at the locations of 8 wells using geostatistical methods. In a large undeveloped oil field in southwest Iran, some carbonate formations encountered abnormal pressure zones. In the area of study, the combined velocity field was improved and calibrated; then, the pore pressure cube was generated accordingly. The predicted pressures show good agreement with the measured pressures at the 8 well locations.
- Badri, M.A., Sayers, C.M., Awad, A. and Graziano, A., 2000. A feasibility study for pore-pressure
- prediction using seismic velocities in the offshore Nile Delta, Egypt. The Leading Edge, 19:
- 1103-1108.
- Bowers, G.L., 1995. Pore pressure estimation from velocity data: Accounting for pore pressure
- mechanisms besides undercompaction. SPE Drilling and Completion, 10: 89-95.
- Carcione, J.M. and Helle, H.B., 2002. Rock physics of geopressure and prediction of abnormal pore
- fluid pressures using seismic data. CSEG Recorder, 27, 7: 9-30.
- Chambers, R.L., Yarus, J.M. and Hird, K.B., 2000. Petroleum geostatistics for nongeostatisticians,
- Part |. The Leading Edge, 19: 474-479.
- Chopra S. and Huffman, A., 2006. Velocity determination for pore pressure prediction. CSEG
- Recorder, 31, 4: 28-44.
- Cibin, P., Martera, M.D., Buia, M., Calcagni, D., Runcer, D.J. and Talkan, T., 2004. What
- seismic velocity field for pore pressure prediction? Expanded Abstr., 74th Ann. Internat.
- SEG Mtg., Denver: 1531-1534.
- Clarembaux, J.C., Giusso, M., Gullco, D., Miranda, C.C., Leiva, J.G.L. and Altamirano, S.A.S.,
- Seismic pore pressure prediction without well data and poorly defined normal
- compaction trend lines. A case study from the Rio Bravo delta, northern Mexico. Expanded
- Abstr., 75th Ann. Internat. SEG Mtg., Houston: 1227-1231.
- Den Boer, L.D., Sayers, C.M., Nagy, Z.R., Hooyman, P.J. and Woodward, M.J., 2006. Pore
- pressure prediction using well-conditioned seismic velocities. First Break, 24: 43-49.
- Dodds, K.J., Dewhurst, D.N., Siggins, A.F., Ciz, R., Urosevic, M., Gurevich, B. and Sherlock,
- D.H., 2007. Experimental and theoretical rock physics research with application to reservoir,
- seals and fluid processes. J. Petrol. Sci. Engin. 57: 16-36.
- Dutta, N., Mukerji, T., Prasad, M., and Dvoorkin, J., 2002, Seismic detection and estimation of
- overpressures part II: field applications. CSEG Recorder, 27, 7: 58-72.
- Eaton, B.A., 1975. The eq. for geopressure prediction from well logs. SPE 5544.
- Gregory, A.R., 1978. Aspects of rock physics from laboratory and log data that are important to
- seismic interpretation. In: Payton, C.E. (Ed.), Seismic Stratigraphy-Applications to
- Hydrocarbon Exploration. AAPG, Memoir 26, Tulsa, OK: 15-46.
- Hirsche, K., Boerner, S., Kalkomey, C. and Gastaldi, C., 1998. Avoiding pitfalls in geostatistical
- reservoir characterization. A survival guide. The Leading Edge, 17: 493-504.
- Hohn, M.E., 1998. Geostatistics and Petroleum Geology. Kluwer Academic Publishers, Dordrecht,
- Netherlands.
- Kan, T.K., Kilsdonk, B. and West, C.L., 1999. 3-D geopressure analysis in the deepwater Gulf of
- Mexico. The Leading Edge, 18: 502-508.
- Kan, T.K. and Swan, H.W., 2001. Geopressure prediction from automatically-derived seismic
- velocities. Geophysics, 66: 1937-1946.
- Kelly, M.C., Skidmore, C.M. and Cotton, R.D., 2005. Pore pressure prediction for large surveys.
- Expanded Abstr., 75th Ann. Internat. SEG Mtg., Houston: 1239-1243.
- Lee, S., Shaw, J., Ho, R., Burger, J., Singh, S. and Troyer, B., 1999. Illuminating the shadows:
- tomography, attenuation and pore pressure processing in the South Caspian Sea, J. Petrol.
- Sci. Engin., 24: 1-12.
- Lee, W.B. and Xu, W., 2000. 3-D geostatistical velocity modeling: Salt imaging in geopressured
- environment. The Leading Edge, 19: 32-36.
- Sayers, C.M., Johnson, G. M. and Denyer, G., 2002. Predrill pore pressure prediction using
- seismic data. Geophysics, 67: 1286-1292.
- Snijder, J., Dickson, D., Hillier, A, Litvin, A., Gregory, C. and Crookall, P., 2002. 3D pore
- pressure prediction in the Columbus basin, offshore Trinidad & Tobago. First Break, 20:
- 283-286.
