Font Size: a A A

Study Of Fine Reservoir Description At Arys Oilfield Of South Turgai Basin In Kazakhstan

Posted on:2012-10-08Degree:DoctorType:Dissertation
Country:ChinaCandidate:S L WangFull Text:PDF
GTID:1100330332488739Subject:Oil and gas field development project
Abstract/Summary:PDF Full Text Request
Fine reservoir description is a multidisciplinary approach with clarifying the fine geological feature,regularity and control factor of remaining oil distribution and providing fine geological model to improve the development efficiency and recovery ratio.Arys Oilfield that locates in the South Turgai Basin of Kazakhstan is very complex according to geological feature and test documents. The article is about fine reservoir description according to seismic data, documents of core, well logging, laboratory findings and dynamic production. The results indicated that:6 middle datum cycles and 15 short-term cycles is built in the Arys Oilfield with high resolution sequence stratigraphy due to the complex stratigraphic sequence and great difference of sedimentation thickness; Delta plain subfacies in Cretaceous reservoir and delta front subfacies in upper Jurassic reservoir are deposited. Distributary channels are main sand body. There is the distribution range restriction,varied thickness and high directivity of sand body; Cretaceous structure,which is sedimented unconformablly above Jurassic stratum,is anticline structure with partly gentle slope, Jurassic structure,which is anticline structure sedimented above Palaeozoic bedrock uplift being complicated by east dip faults,can control distribution of oil and water due to the steep slope in the east and gentle slope in the west and complex structure and faults; The criterion of identification of oil gas and water with different horizon and lithology and logging data reinterpretation models are established according to the core analysis and test data to calculate reservoir physical parameter; The reservoir mainly consist of packsand and siltstone with middle-porosity and low-permeability in Cretaceous reservoir and middle-high porosity and high-permeability in Jurassic reservoir; The reservoir thickness changs quickly and causes layer heterogeneity. The results in physical properties and productivity varying greatly both laterally and vertically , unbalance producing reserves and cause strong plane and vertical heterogeneity; Flow unit can be classified into three types: Unitâ… is frame sand,Unitâ…¡is mouth bar and crevasse splay and Unitâ…¢is fore sand sheet and natural levee,which alternates fast laterally and vertically; Lower Crataceous reservoir, which mainly consists of structural pool of smooth anticline, is edge water one with gas cap. Upper Jurassic reservoir located in the eastsouth of the structure is structural-lithologic reservoir of overlap. The geologic reserves have been recalculated; Flow unit restraint was used to establish 3-D property model during establishing 3-D Geological modeling by PETREL and the reliability of the model was inspected by spot-check and reserves comparison; The viewpoint of"layer subdivision and implementation step by step"is made by applying test documents to analyse the producing and potentiality of the reservoir.The research, rooted in and applied to the production, provided the scientific geological basis for improving the development efficiency and adjusting top potential of the oilfield to develop the fine reservoir description technique of this kind of complex reservoir. According to the research, 7 new wells have been implemented and stimulation treatment have been proposed for 35 times or wells with efficiency rate 86.5% and increasing production 17845t totally for two years. The suggestion of development well site on the basis of the research has been accepted and implemented.
Keywords/Search Tags:Arys Oilfield, Fine Reservoir Description, Sedimentary Microfacies, Reservoir Heterogeneity, 3-D Geological Modeling
PDF Full Text Request
Related items