Comparison of hydrocarbon generation,expulsion periods,and accumu-lation periods of source rocks in Member 7 of the Yanchang Formation in the Jinghe Oilfield,southern Ordos Basin
Comparison of hydrocarbon generation,expulsion periods,and accumu-lation periods of source rocks in Member 7 of the Yanchang Formation in the Jinghe Oilfield,southern Ordos Basin
[Objective]Commercial oil accumulation in the Jinghe Oilfield of the Southwest Ordos Basin was pri-marily found in the Northeast area.Previous studies have shown that oil mainly sourced from the oil shale in Mem-ber 7 of the Yanchang Formation.However,whether the oil comes from the source rocks spatially located in the Jinghe Oilfield or the basin center has not been determined,which inhibits further exploration of the Jinghe Oil-field.[Methods]In this paper,the hydrocarbon generation and expulsion history of source rocks in Member 7 of the Yanchang Formation in different tectonic parts of the Jinghe Oilfield and in the basin center have been recon-structed through basin simulation.Then,the accumulation periods of oil in the Yanchang Formation reservoir have been identified using fluid inclusion technology.[Results]The time window comparison of the oil accumulation in reservoir and the hydrocarbon generation and expulsion of source rocks show that oil in the Jinghe Oilfield limitedly came from the source rocks beneath the Jinghe Oilfield but more widely came from source rocks in the basin center.The oil in the Jinghe Oilfield generally shows the migration direction from Northeast to Southwest.[Conclusion]Therefore,unlike the traditional model of short-distance vertical migration,a new model can be established as that,the oil in the Jinghe Oilfield mainly laterally migrated from the hydrocarbon kitchen in the basin center along the strike-slip fault belt.The research results can provide an important reference for the prediction of hydrocarbon accu-mulation zones in the Jinghe Oilfield.
关键词
盆地模拟/流体包裹体/热史/埋藏史/油气运移/烃源岩
Key words
basin modeling/fluid inclusion/thermal evolution history/burial history/hydrocarbon migration/source rock
维普
万方数据