Sequence stratigraphy and sedimentary systems development model under the control of syn-depositional faults and paleo-geomorphology of the Paleogene Shahejie formation in the northern Kendong uplift in the Bohai Sea area
Kendong Uplift is located on the western side of Laixi fault in the Bohai Sea segment of the Tanlu Fault Zone.It is charactered with complex tectonic evolution,diverse sedimentary fillings,shallow buried depth and sand-rich deposits,which is believed with good condition for oil/gas accumulation or sandstone-type uranium deposits and an important exploration area in Bohai Sea.This study focused on the sedimentary development under the high resolution sequence stratigraphy framework of Paleogene Shahejie Formation in the northern section of Kendong uplift and has set up the development and distribution model of source-sink sandy sedimentary system on the background of paleouplift-paleogeomorphology controlled by the syn-depositional fault activities,which will provide an important reference for favorable reservoir facies zones prediction.The study identified two 3rd order sequences(SQ_Es3 and SQ_Es1)and four 4th sequences of Ssq-1,Ssq-2,Ssq-3 and Ssq-4.Ssq-1,Ssq-2,Ssq-3 deposited in the low stand system tract and transgressive tract and mainly developed fan delta,near shore subfan,and deep lake,showing rapid filling and proximal accumulation characteristics.Ssq-4 formed in the high stand system tract and mainly developed lacustrine delta.SQ_Es1 is lack of low stand system tract,mainly developed transgressive tract and high stand system tract,with the characteristic of shallow lake clastic bar and carbonate shoals.The syn-sedimentary fault activities controlled the rapid subsidence and the development of the proximal fan deposits in the steep and slope area.Along the direction of the fault zone,the regulation of the fault end promoted the formation of the valley or channel and controlled the remote source transportation and the construction of the source-channel-sink system from the paleouplift-slope zone to deep depression area.Fan delta front sandbodies developed on the edge of paleouplift of SQ_Es3 and lacustrine bar sandbodies of SQ_Es1 are the favorable reservoir targets for oil-gas exploration.
Bohai Bay basinKendong upliftShahejie formationsequence and sedimentary systempaleouplift and paleogeomorgraphy
万方数据
维普
