| The research on source-to-sink system has gradually become a research hotspot and difficulty in the field of sedimentology,which is vital for understanding the developmental and evolutional characteristics of sedimentary system in spatio-temporal dimension.The upper section of the Fourth Member of Shahejie Formation to the lower section of the secomd member of Shahejie Formation were taken as the research objects.The rich research datas were used in this work included seismic data,drilling data,logging data and analytical test data.On the guiding of research concept of “Source-Channel-Sink-Time”,this research work analysed the characteristics of the three components of source-to-sink system,to discuss the type of the peleogene source-to-sink system of the northern steep slope of Dongying Sag and its developmental and evolutional characteristics in spatio-temporal dimension,thus to summarise the sand bodies distribution under the control of source-to-sink system evolution in spatio-temporal dimension.According to the characteristics of source rock,structure,climate and catchment area of source area,the Chenjiazhuang uplift is divided into three sources area: Lijin,Shengtuo and minfeng area.During the period of Es4 s deposition,the study area develops intensive structure activities and the weather about dry to wet.The catchment area of Chejiazhuang uplift is the largest and the group of Mesozoic to Archaeozoic attend to supply source into the basin.The provenance supply ability of Chejiazhuang uplift is the strongest in the period of Es4s-Es2 x deposition and the provenance supply capacity of Minfeng area is the worst between the three sources area.In the Es3 x sedimentary period,the tectonic activity is still strong and the climate became humid.The catchment area of Chejiazhuang uplift decreases gradually and the Archaeozoic became the major source layer.The provenance supply ability of Chejiazhuang uplift decreases dramatically.The provenance supply capacity of Shentuo area is relatively strong between the three sources area,because Paleozoic and Mesozoic has higher percentage in the source rocks of Shentuo area.During the period of Es3 z deposition,the tectonic activity intensity decreases.The source area is enlarged and the weathering denudation time is long.Climate and source rock inherite the last period and the provenance supply capacity of Chenjiahzhunag uplift remained basically unchanged.During the period of Es3 s deposition,the tectonic activity intensity decreases dramatically and Archaeozoic's percentage in the source rocks increases.The provenance supply capacity of Lijin area and Shentuo area decreases dramatically,but the provenance supply capacity of Minfeng area increases slightly.During the period of Es2 x deposition,the tectonic activity is weak and source rocks remain unchanged.The climate shifts from wet to dry gradually and the catchment area increases,the provenance supply capacity of Chenjiahzhunag uplift grows.There are three kinds of source channels of paleovalley,tectonic transition zone and paleoslope in the research area.The development and evolution of three kinds of transportation channels in spatio-temporal dimension control the evolution of sediment transport capacity.In temporal dimension,the transport capacity became weak gradually in the period of Es4s-Es2 x deposition.In spatial dimension,the transport capacity of Shengtuo area and Minfeng area is relatively strong and the transport capacity of Lijin area is the weakest in the period of Es4s-Es3 x deposition.The transport capacity of Minfeng area is the strongest and the transport capacity of Lijin area is is the weakest in the period of Es3z-Es2 x deposition.In the period of Es4s-Es3 x deposition,there are nearshore subaqueous fan,fan delta,diluvial fan and sublacustrine fan primarily deposited in sink area and superimposed covered between fan bodies.In the period of Es3z-Es3 s deposition,the sedimentary facies deposited in sink area including nearshore subaqueous fan,fan delta and delta.The deltaic primarily deposited in sink area during the period of Es2 x deposition.The Paleogene source-to-sink system of the northern steep slope of Dongying Sag belongs to the type of ancient Source-to-sink system of steep slope belt.The Paleogene source-to-sink system of the northern steep slope of Dongying Sag develops 5 kinds of source-to-sink coupling model,including(1)uplift-ancient valley-nearshore subaqueous fan(-sublacustrine fan)source-to-sink coupling model,(2)uplift-ancient valley-fan delta(-sublacustrine fan)source-to-sink coupling model,(3)uplift-transfer zone-fan delta/ sublacustrine fan source-to-sink coupling model,(4)uplift-ancient slope-diluvial fan source-to-sink coupling model,(5)uplift-ancient valley-delta source-to-sink coupling model.Lijin area mainly devolep the second type of source-to-sink coupling model.Shentuo area devolep the frist and third types of source-to-sink coupling model in the period of Es4s-Es3 x deposition,the second type of source-to-sink coupling model in the period of Es3z-Es3 s deposition and the fifth type of source-to-sink coupling model in the period of Es2 x deposition.Minfeng area mainly devolep the first type of source-to-sink coupling model,furthermore,devolep the fourth type of source-to-sink coupling model in the Es4 s deposition period and the fifrth type of source-to-sink coupling model in the period of Es3x-Es2 x deposition.The control action of source-to-sink syetem on sedimentary sand body includes: the structure and activity of the main fracture controlled the genetic types of sedimentary system;the supply capacity of source area controled the scale of the sedimentary body;the transport capacity of the source channel did not control the size of the sedimentary body,but its development position controled the direction of the provenance transport.the position of the development of the sedimentary body is controlled by the combination of the source channel and the slope folding belt. |
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