Sedimentary Characteristics Research Of The Gravity Flow Of Qingshankou Formation In The Northern Songliao Basin

Based on Northern songliao basin3D seismic projects，with the help of sedimentologyand sequence stratigraphy, we make several seismic sedimentological studies on the basis ofisochronous sequence stratigraphic framework, restore the history of the evolution ofsedimentary filling, and put forwqard the favorable exploration targets.The sedimentary history of the Qingshankou Formation is restored. QingshankouFormation mainly developed the western provenance and northwest provenance depositions,followed by the deposition of northern source. The datum level of the whole QingshankouFormation is declining gradually, mainly developed lacustrine facies in the lower depositionalpart, and development into the plot type delta depositional system.in the upper part. Eastprovenance developed after the third section of Qingshankou Formation.Seismic geological body recognition templates are established, the template s includemultiplicative delta, distributary channel, mouth bar, sheet sand, gravity flow, ostracodlimestone and so on.There develops3tectonic slope-breaks in the west of Changyuan. The tectonicslope-breakⅠcontrols the gravity flow in Gulong area, tectonic slope-break Ⅱcontrols thedelta and flake turbid flow deposition in the nose structure of Longnan area. The tectonicslope-break Ⅲ controls the delta of Changyuan area.There develops the conventional reservoir, the tight sandstone reservoir, the thin layersreservoir in shale these4types of reservoir.There are a variety of types of gravity flow reservoir developde in the QingshankouFormation, we can identified sliding rocks, slumping rocks, sandy debris flow, turbidites andso on from gravity flow sedimentary structures. It has a special accumulation model, wecalled it, hydrocarbon booster, to-way active hydrocarbon expulsion, migration andaccumulation near the source and advantages filling. Gravity flow deposits are related todeposition slope break, earthquake and flash floods.The favorable exploration targets are predicted for the gravity flow reservoir and tightsandstone reservoir of the lacustrine zone in Qingshankou Formation. The most favorableexploration targets of the gravity flow reservoir are sandy debris flows mainly distributed inYingtai-talaha slope and Gulong gravity flow channel deposition.