The Paleogene Clastic Reservoir Characteristics And Lithologic Stratigraphic Traps Identification And Evaluation In The East Area Of Liaohe Beach

Lithologic stratigraphic reservoirs are currently liaohe oil and gas exploration downwarped area of new hot fields and realistic goal.Comparing with the land of liaohe,the beach area is relatively at low level of prospecting,whose main subject is structure traps.Using the successful lithologic reservoir exploration's experience of the liaohe downwarped area,with the aid of newest domestic theory and method or abroad,the breakthrough of the liaohe beach area lithologic reservoir exploration's realization has important strategic significance.This article made further research work by using existing research data of the eastern region,the sequence stratigraphic analysis,and seismic technology.First step,determine the favorable sand body and its position by drilling data,horizon contrast and faultage interpretation;then find out the lithologic trap developmental pattern with seismic inversion;finally determine the lithologic stratigraphic reservoirs'favorable zones for development.The paleogene reservoir rock types of the eastern of Liaohe seabeach are mainly feldspar lithic sandstone and litharenite;reservoir space is mainly about secondary and mixed pore,including between grains pores,mould holes,intragranular pores and fissure,etc.Paleogene reservoirs of eastern Liaohe beach has two secondary porosity belt,the first area eaqual to the precocious rock B-late diagenetic rock A1 stage,buried depth in 1,400 to 2,600 meters,mainly controled by carbonate cementation and dissolved feldspar;the second area equal to the late diagenetic rock A2 stage at 2,800 to 3,400 metres,mainly controlled by the dissolving of debris and siliceous cement.Through the elaborate sequence division of the research area,it founded that base-level changing not only controled the feature of the sand body's longitudinal fold and the horizontal distribution,while also controled reservoir stratum property.At the low base-level position,sand body vertically stacked closer,horizontally extended further and its petrophysical feature are relatively good.It is favorable conditions for development of the reservoir stratum.Meanwhile the sequence stratigraphic framework controled the development of different kinds of lithologic stratigraphic traps,low water period it developed sublacustrine fan,slope fan sand body;water into period it developed super coated sand body,high period it developed delta sand body,in its frontier can development slump sand body.This paper mainly used the seismic profile of different types of lithologic trap,governing factor of different lithologic stratigraphic traps to look for development pattern of different trap types.It used geophysical inversion technology to predict the scale of the trap.The major types of lithologic stratigraphic traps in the east Liaohe beach are sandlenstraps and sandstone pointed out pour traps and turbidite sandstone trap and qianshan traps.Its main developed layer is dongying group 2,dongying group 3,shahejie groupl?2,including the sublacustrine fan,pointed out its trap,beach dam and high slump fan,etc.