Stratigraphy And Facies Of Dongying Formation,East Chengdao,Jiyang Depression

This thesis is based on high-resolution sequence stratigraphy and sedimentary petrology theory,and in combination of logging and 3D seismic,to study the sedimentary system,stratigraphic framework,and its reservoir distribution of Dongying Formation in east slope of Chengdao,Jiyang Depression.Analysis of the sedimentary sequence,main controlling factor of the reservoir distributionin,trap types in the study area of Dongying Formation helps to proposed study area's favorable reservoir and trap types.The Dongying Formation is a second-order sequences,and can be divided into four third-order sequences,from bottom to top which named as SQ4?SQ3?SQ1.It is a classic continental rift-depression conversion basin that performances as base level fall.Its lower part is developed by the fault system which has high accommodation in high base levelphase,develops turbidity fan system.As fault movement faded,the middle part is formed by braided delta system in the phase base level fall.According to the base level fall and basin fill,downstream fluvial system occupies the upper part of Dongying Formation.The Dongying Formation sequence as bottom turbidite fan in fault period,braided delta system in rift-depression period,and distal low-sinuosity fluvial system in late depression period.Synthesis of high resolution sequence stratigraphy and sedimentary characteristics in the study area,and combined with analysis of tectonic,paleogeomorphology,the study area is divided into three tectonic belt,such as in west slope belt ?,? southeast Chengbei 30 buried hill and northeast sag zone III,and favorable reservoir zones are predicted in the help of seismic inversion.Through the accumulation model research,four reservoir types arelithologic reservoir,lithologic-structural reservoir,structural-lithologic reservoir,stratigraphic overlap reservoir.Distribution of turbidity fan in Dongying Formation is mainly controlled by the palaeogeomorphology and structural factor,therefore,slope-break zone is the favorable target for reservoir.