Research On The Original Appearance Restore In Shahezi Stage Of Lishu Rift

Lishu irtf located in the Southeast upswelling area of Songliao basin, to overlay complexdeposition depression is a typical fault sag. The irtf period occurred in Early Cretaceous Epoch.Shahezi stage is one of the ritf depression peirod of Lishu ritf, the hydrocarbon source rocksdevelopment in the stage, it is one of the important exploration target horizon. However, thelack of detailed study of its oirginal appearance for a long time, and constraints of the targethorizon to oil and gas exploration.In inspection, collection, sorting on the basis of previous research data, to combine Lishuirtf well drilling，well logging and seismic data. Use of Balanced-section Technique structuraland analysis of the Lishu ritf within Xiaokuan fault belt, Qinjiatun fault belt, Pijia fault belt,Sangshutai fault belt in Shahezi stage to structure, structural assemblage and their properties,discusses the sedimentary features of Shahezi stage, and recover the original visage of Shahezistage.The results show that: Shahezi stage in the Lishu irtf distirbution is more limited, overalldevelopment controlled by fault depression, that is fault in the west and transgression in theeast in tectonic style, and that is thicker in the west and thinner in the east in formationthickness. Shahezi stage can be divided into four subpirme tectonic unit, they are Shiwu deepdepression, eastern slop, Shuanglong depression, Sujiatun depression. Furthermore, it can bedelimitated to three secondary structural belts, Xiaokuan fracture belt, Qinjiatun fracture beltand Sangshutai steep fracture belt. Shahezi stage,Lishu rift mainly developed fan delta front,fan delta plain, deep lake, shallow lake, offshore lake，nearshore fan sedimentary facies etc,locally developed underwater turbidite fan.