Method Of Isochronous Stratigraphic Division And Correlation Using In The Red Beds On The Southern Slope Of Dongying Sag

The research on sedimentation, reservoir and hydrocarbon exploration from the lower fourth member of Shehejie Formation to Kongdian Formation, Dongying Sag have been prohibited for lack of effective method using in the stratigraphic division and correlation. Basing on detailed biostratum research, core observation and geophysical explanation, this paper focused on optimizing a proper correlation method for red layer to build a correct and reasonable equitime stratigraphic framework and ascertain the sedimentary system type and distribution regularity in studied area, for the purpose of guiding our next exploration.There are mainly three sedimentary types in studied area such as alluvial fan, beach bar and shallow lacustrine-flood- over lake. The climate is relatively dry during the first member of Kongdian Formation period, and the whole basin has shallow sedimentation with the lake plane dominated by sudden flooding. Alluvial fan and flood-over lake sedimentary systems chiefly developed in the south slope. As to the lower fourth member of Shahejie Formation, the climate became wetter and the water body was deeper, alluvial fan was mainly formed on the edge of the basin and flood-over lake sedimentary system began to evolve to shore-shallow lacustrine.Through comparison and analysis of Classic sequence stratigraphy and high-resolution sequence stratigraphy, all theory of sequences has unified theoretical basis, that is, formation of the cycle. Classic sequence stratigraphy takes the identification of unconformities and tracking sequence as the starting point that have great significance for the establishment of regional and macroscopic sequence stratigraphic framework of the rifted basin which caused by tectonic activity. As the starting point of the method from the high-resolution sequence stratigraphy represented by Cross, identification and tracking of stratigraphic datum fluctuation changes have more advantages for the establishment of conformity stratigraphic framework. We can connect into them by flooding surface.During the ES4-EK,the lake level mianly controlled by seasonal flooding, Deposit Response has large difference between the increasing and the descending base level. There are obviously dichotomy in vwetical.This research utilize a multi-science comprehensive division method which was restrainted by seismologic data, on the basis of paleontological data, taking wavelet transform as centre, advocating the subsidiary role of logging and ithologic information. Finally, K₂ formation was divided into three sequences and the lower member of ES₄ was divided into two sequences through dividing and correlating sequence in the whole area using seismic section. Moreover,we divide into the cyclostratigraphy seriously for their inner.Associated with the detailed research in an important hydrocarbon exploration part of the red beds,it is concluded that the oil-bearing fault controlled oil zone and strata. Sedimentary face effect on type of oil reservoir . in liang 120 block ,it mainly develops underwater shallow beach and It grows mainly the fault-lithologic reservoir. in the oil-bearing strata in Gao89 block, where develops Alluvial Fan and forms lithologic reservoir.