Methods and Techniques of Lithological Reservoir Exploration in Southwestern Qaidam Basin

There is abundant remaining petroleum in the southwestern Qaidam basin.In the past,more attention was paid to find structural reservoir than lithologic reservoir.In recent years,under the guidance of exploration methods of lithological reservoirs,that is hydrocarbon enriched in depression,accumulated in slope zones,petroleum-bearing new layer searched,and superposition continuity explored,the breakthrough of petroleum exploration in Hongliuquan slope and Wunan slope of southwestern Qaidam basin was gotten.The discovery of large scale special lithologic reservoir in Yuejin slope was done.Since the low degree of exploration and limited know about lithological reservoir,the exploration of lithologic reservoirs in the southwestern Qaidam basin is still on exploratory stage,and a set of mature and effective methods are not formed yet.Based on exploration achievement of lithologic reservoirs in Qaidam basin,a set of methods fitting for lithologic exploration in the Qaidam basin was gotten,in combination with successful exploration experiences in other basins.These main methods included re-examination of old wells,classification of sequence stratigraphy,division of sediment system and integrated reservoirs prediction.Good petroleum exploration in Qaidam basin was gotten by these integrated methods with industrial flow for many wells.