Study On The Sequence Stratigraphy And Sedimentary Facies Of Upper Jurassic And Lower Crataceous Of ADM Area

ADM area is located in the southeastern part of South Turgay Basin of Kazakhstan. With the development of exploration,subtle reservoir has been thought of a focal point of exploration.It is difficult to find channel sand bodies with Sequence stratigraphy and sedimentology.According to the classical principles of sequence stratigraphy,Upper Jurassic and Lower Crataceous is divided into two 3rd order sequences and four systems tracts by the application of the SP curve wavelet transform and identification marks of sequence boundary,including lithologic characteristic,wavelet analysis, seismic section and so on.According to integrated study on drilling cores,well logging and seismic data,it is believed that the J3ak of Upper Jurassic is meandering river sediment and the K₁nc₁ar of Lower Crataceous is braid river sediment in ADM area.For the sedimentary characteristics,fluvial microfacies,including of the flood plain,crevasse splay, marginal bank and channel floor lag of Meandering River,point bar and braided channel of Braid River,are identified by using sedimentological theory and three-facies combination method.The paper discussed the main difference of Meandering River and Braid River.Base on the analysis of structural and geostatistic,the new earthquake prediction chart was made by using the technology of seismic comprehensive prediction,that is superimposed Conventional seismic attribute optimization and Cumulative frequency properties,the chart remove ambiguity in seismic research,and predict the distribution of fluvial microfacies.Compare with conventional seismic attribution technique,this new technique can forecast river microfacies distribution case more accurate.The fluvial microfacies of ADM area is got by analyzing single well,correlation profile and plane diagram,and it can be used to guide exploration of depositional trap.The paper also discussed the controlling factors of fluvial microfacies and analyses the fluvial facies distribution which effected by the palaeogeomorphology, palaeoclimate,palaeoprovenance,structural evolution and fault system.Tectonic evolution analysis indicates that Bulinov area provide a small amount of source in the early SQ8 and start receiving little deposition in later period of SQ8,then accept the thick sedimentary in SQ9 period.It is believed that the fault controlling depressed area dominates the area of rivers,and the contemporaneous fault dominates the location of channels.