Hydrocarbon Forming Pattern And Favorable Block Prediction Of Putaohua Formation In Songfangtun Concave Slope Area

Songfangtun concave slope area is a succession nose shape structure slope as well as Sanzhao depression of Songliao basin developing process,Putaohua formation is most important contains oil goal formation in this area center lower part to contain oil combines,since long ago,the forming law is not unclear to be recognized,based on the theories and means of sedimentology,sequence stratigraphy,petroleum geology and so on,from the fine research of palaeostructure,sequence frame work sedimentary facies,forming period,hydrocarbon water distribution,trap type,and generalize on hydrocarbon forming pattern and enrichment law,pointed out new objects and orientation of exploration and development,had important instruction significance of hydrocarbon genesis and prediction of Sanzhao depression.This article from Sanzhao depression and the peripheral palaeostructure evolution obtains,had conducted the scrutiny to palaeostructure of Songfangtun concave slope area,summary four stages which palaeostructure evolves,and initial found Songfangtun-Mofantun ancient nose structure,had known the palaeostructure control action to the hydrocarbon migration.In the palaeostructure research foundation,through to bed thickness,sandstone thickness research of Putaohua formation,ascertain this area for the north sole source,belongs to north the depositional system of Songliao basin,is delta plain and delta front which extent from the Changyuan-Shaertu,Xingshugang water system to Taipingtun,Songfangtun.The application sedimentology,high resolution sequence stratigraphy theory carries on the division to Putaohua formation,had established high resolution sequence framework,know middle loss as well as syndeposit uplift in south this research area,And research through sedimentary microfacies of the key sedimentary units,determine this area is primarily in branch channel and submerged branch channel,the submarine branch channel is extremely narrow,growth,and extend long.Through Xujiaweizi subdepression and Yongle subdepression bury history of source rock research,find hydrocarbon primary migration time for K1n4 of last stages,forming essential time for K2m2 of last stages,and had the new understanding to the hydrocarbon migration field.Basedon Putaohua formation structure,sandstone,staticstate,performance,abandoned well and hydrocarbon water interface aspect and so on studies,priority analyzed 31 type trap,summarized four type hydrocarbon forming pattern of Songfangtun concave slope,and pointed out'the sole local structure' host controlled hydrocarbon factor,in forming law under the instruction,had forecast the development zone peripheral advantageously proved hydrocarbon area and the advantageous clear area.