Abnormal pressure strata are believed to exist throughout the Malay Basin with the exception of the southwest and northeast margins. The onset of abnormal pressure is abrupt in the northeastern portion of the basin but is generally more gradual in the southeastern area.

The abnormal pressure is a complex origin and is attributed to a combination of rapid burial of certain stratigraphic units, uplift of initially normally pressure strata, faulting and hydrocarbon column effects.

Predrill abnormal pressure predictive techniques used by EPMI in the Malay Basin are interpretation of seismic interval velocities and electric log correlation. With accurate seismic velocity information, an interval transit time profile, called a Pennebaker plot has aided in predicting top of abnormal pressure in 80% of the wells drilled to date. Log correlation is most applicable within the confines of a particular structure.

Detection of abnormal pressure in the Malay Basin while drilling is difficult at standard pressure indicators while drilling and use of industry generated overlays to derive quantitative estimations of pore pressure from drilling exponent plots do not provide satisfactory results. As a result, EPMI developed a "Malay Basin" overlay which provides more accurate quantitative estimation of pore pressure from drilling exponents. In addition, EPMI employs a technique for monitoring gas feed-in, called an extended connection, or 10-10-10 to detect geopressure while drilled.

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