The Sedimentary System Of Middle Es3Formation Of The Daluhu Sand Body Of The Dongying Depression

In this paper, the Daluhu area of Boxing Sag in Dongying Depression is chosen as the study zone and the middle Es3Formation of Paleocene is taken as the target intervals. Based on the tectonic setting of the study area, and combined with theory of classic sequence stratigraphy, sedimentology, the data of drilling core, well logging, the single well and cross section sequence is divided and the regional sequence framework is established. Then, with the result of analyzing the characteristics of vertical evolution and plane distribution the main achievements and understanding of this paper are below:Vail sequence stratigraphy principles and related methods is applied to establish the scheme of sequence stratigraphic of the area, and at the same the middle Es3Member of Daluhu area in Boxing sag are divided into two third-order sequences, from the bottom to top, namely, sequence1, sequence2; and they can be subdivided into six systems tracts. And sequence stratigraphic framework is established as well.Based on core observation, the depositional environment of the middle Es3are concluded as river delta-lacustrine depositional system, identify the delta front, shallow lake sand semi-deep lake facies,further divided in tounder water distributary channel,between under water bay, estuary dam,sheet sand,beach bar,shallow lake mud turbidites,mud, and other semi-deep lake sedimentary micro facies SedimentaryIn sequence stratigraphic analysis, basic types of sedimentary facies and provenance analysis reveals the spatial distribution law depositional system within the sequence stratigraphic framework, low stand systems tract of ESQ1relatively high percentage of sandstone,mud stone major bottom, gray mudstone,sand stone and upward development of delta sand beach bar,delta mainly developed in the west;Transgressive systems tract of ESQ1is the deepest lake during the invasion of the domain, mainly mudstone, shallow lakes and semi-deep lake sediments, develope da small distal turbidites; highstand systems tract of ESQ1depth stable,mainly developed shallow lake dam.Transgressive systems tract of ESQ2is the deepest lake during the invasion of the domain,as shallow lake dam and semi-deep lake sediments, mainly mud stone and shale sandstone, develop mental distal turbidites;highstand systems tract of ESQ2is mainly developed delta and shallow lake sediments.Favor able reservoir sand body typecast achieve a certain thickness and size of the distal turbidites, mainly in the fields.