Publications

In oil fields while drilling exploratory wells one is often confronted with various unexpected problems. One such problem isabnormal pressure which should be counter balanced with mud weight.Predictions of formation pressure or estimates of mud weight required may be undertaken by using seismic data and other data of a neighbouring well, such as has been done by HOTTMANN, JOHNSON and BELLOTTI, GIACCA.The method of modifying predictions for determining the tentative mud weight has been already used in exploration wells in the work areas of PERTAMINA Unit EP I and Unit EP III. Tentative mud weight determination is based on geophysical data (seismic interval velocity) and data of the nearest well to the location. The accuracy of such determinations is very much dependent on the precision of the above data.Statistics show that errors are in the range of 5 - 10%.