Abstract:

The prediction on distribution area of favorable reservoirs is an important research field in petroleum exploration. In practice, some routine methods have been taken to conduct research. For example, sedimentology and reservoir geology, in combination with seismic and well log information, have been used to predict the reservoir horizontally and vertically. However, the problem resulted is long period of research and huge investment. Therefore, a convenient method for predicting reservoir has being probed. After the observation on Shahejie formation, Qingshui area of western depression of Liaohe basin, it is found that the sandstone in the intervals of under-compacted mud rock might be favorable reservoirs and the oil and gas reservoirs are mainly distributed in the intervals of under-compacted mud rock. Therefore, the characteristics of under-compacted mud rock could be used to predict the distribution area of favorable reservoirs. It is finally shown that under-compaction of mud rock is closely related to the formation of reservoir, petroleum migration and the distribution of oil and gas reservoirs in mechanism. By using the curve of under-compacted mud rock, the horizontal and vertical distribution of favorable reservoir could be predicted. Combined with the comprehensive analysis on other factors, the oil and gas reservoirs as well as their distribution area might be recognized.

Key words: under - compaction of mud rock, reservoir, petroleum migration, oil and gas reservoir