Study On Sedimentary Characteristics Of Es3and Es4Member In The South Slope Belt Of Linnan Sub-depression

The south slope belt of Linnan sub-depression including Linnan sag and Huimin southslope areas have advantageous conditions for hydrocarbon accumulation. Up to now, many oiland gas fields have been discovered, the main Petroleum Pools of which are structuralPetroleum pools. The sequence stratigraphv, Provenance system, and the genesis anddistribution of sand bodies of the third and fourth member of the Shahejie formation in thesouth slope belt of Linnan sub-depression were systematically studied by application of thetheories and methods of sequence stratigraphy, sedimeatology, and petroleum geology. Thestudy promoted the exploration of subtle Pools in the south slope belt of Linnansub-depression.Based on the comprehensive analysis of seismic, well drilling and logging data, the thirdand fourth member of Shahejie formation in south slope belt of Linnan sub-depression can bedivided into five the third order sequences. The lower Part of Es4is sequence Cl, the upperpart of Es4is sequence C2, the lower part of Es3is sequence C3, the middle part of Es3andthe third member of the upper part of Es3is sequence C4, the first member and the secondmember of upper part of Es3and the second member of lower part of Es2is sequenceC5.According to Cross,C1is divided into four medium-term base level cycle and C2isdivided into three medium-term base level cycle. According to Vail, C3is divided intoLST,TST and HST, and C4is divided into TST and RST,and C5is divided into LST,TST andHST.There is southern provenance systems in the south slope belt of Linnan sub-depressionexisted during the depositional period of Es3and Es4. The southern provenance system in thesouth slope belt of Linnan sub-depression mainly comes from Luxi uplifted and controls thesand bodies sedimented. In sedimentary facies vertical distribution and a flat distribution characteristics based onthe study, the purpose of the study area layers of sedimentary facies spatial and temporaldistribution has the following law: eatler Es4deposited alluvial fan-floods lake belts; in thelate Es4deposited alluvial fan-fan delta belts;in the early Es3the western deposition delta,fan delta and delta-slump turbidite fans belts, and deposited mainly in eastern alluvial fan–delta, alluvial fan-fan delta and delta-slump turbidite fans belts; in the middle of Es3deposition fan delta–turbidite belts; in the late Es3deposited mainly western lakeside swamp,delta belts,and deposited mainly in eastern delta facies, delta–turbidites belts.The study area destination intervals development of the alluvial fan-fan delta, alluvialfan-braided river delta, and delta-slump turbidite fans in two of the more importantdepositional model.