Sequence Stratigraphy Study And The Prediction Of Subtle Reservoirs Of Es1-2 In South Of Huanxiling Oil Field

The west slope of West sag in Liaohe depression is the well-know slope composite oil-gas accumulation zones , the south of the west sag is calculated the focal exploration area in Liaohe oil field, which have very superior oil geologic conditions. The south of Huanxiling oil field of west sag is favor area for looking for hydrocarbon reservoirs. In view of the features such as complicate the structural environment, the high reservoir heterogeneity, the multivariant lateral facies and so on in region of interest, make use of high resolution sequence stratigraphy, sedimentology, the theory reservoir formation, the high precision seismic interpretation and inversion ,and other advanced theory or technique, This article want to clarify the main control factors for reservoir formation of s₁-s₂ in region of interest, build the mode of reservoir formation, demonstrate the favor exploration direction and potential area, and provide effective geologic reference for the disposition of exploration and exploitation.On the basis of the exploration research result of predecessors, after studying the structural feature, the deposit feature, the feature of reservoir formation of the south of Huanxiling oil field of West sag in Liaohe depression intensively, we find out the favor sand body according to fine 3D seismic interpretation in region of interest, studying high resolution sequence stratigraphy using log and seismic data in region of interest, the superior analysis of sedimentary facies and sedimentary systems, and making a fine description for the space distribution of sand body of s₁-s₂ in region of interest which unite seismic inversion, what is more, we would act favorable objectives prediction and evaluate and deploy preliminary prospected wells associating the study of the law of reservoir formation in region of interest.This article had mainly purchased some items of research result and knowledge as follows: 1, there are main two group fault growing in region of interest, which are a NE-trending group fault dropping westward that growing early and a EW-trending group fault dropping southward that growing late period. The EW-trending group fault is main fault, which control the tectonic framework of region of interest; 2, The s₁-s₂ in region of interest can be divided one second-order sequence, two third-order sequences and eight parasequence sets, which also can be divided six system tract; 3, The s₁-s₂ in region of interest mainly develop fan-delta sedimentary system in shore-shallow environment, the sand body of sub-channel branch of the front of fan-delta, debouch bar, Sheet Sand of front of fan-delta developing relatively more, which are also favor reservoir; 4, The oil source is enough in region of interest, the style of hydrocarbon reservoir is versatile, so the region of interest has favor conditions for formation of subtle trap. The region of interest is situated the slop-break belt of the west slope, the fault have a critical action for the migration hydrocarbon and accumulation;5, we had found three favor subtle trap and forecasted about 10 million ton hydrocarbon resource.