The 301 Blocks South Tuen Set Of Reservoir Description

Bei301block is Huhe-2structure located in Huhenuoren structure of Beierdepression in Hai Laer basin. From reservoir evaluation of the study block, it isknown that Nantun2reservoir is the main reservoir, which is mostly the underwaterdistributary channel and mouth bar of the fan delta depositional bodies. Theprovenance of Huhenuoren oil field is from the western Cuogang uplift, which hasrelatively abundant provenance supply during the Nantun sedimentary formingleading to a larger fan delta bodies. DuringAfter ten years of exploration anddevelopment, the study block has entered the period of development of dense wellnetwork. Injection-production contradictions gradually increase with the explorationand development. It is difficult to realize oilfield high and stable production.Quantitative description of sedimentary properties and reservoir characteristics ofNantun formation in Bei301block can provide the basis for not only the prediction offavorable oil and gas layers of Bei301block, but also the selection of the appropriatemethod for exploitation, which is of great importance to improve the success rate ofdevelopment and economic benefits.The reservoir of Bei301block is mainly concentrated in I, II reservoir group ofNantun2, which have been subdivided during the study. Considering that the studyarea has entered a period of dense well network development, in order to maintainsystematic and integrity of the development layer group, the demarcation of eachreservoir and the number of the original reservoir group are remained. On this premise,a comprehensive and systematic analysis of the core wells and well logging data ismade in the study area. Basing on the marker bed and with reference to the existinghierarchical data of I, II reservoir groups of the Nantun second formation, cyclicityrecession sedimentation sequence, reservoir heterogeneity, thickness and thecorresponding logging curves are analyzed in order to achieve the stratigraphicdivision and comparison. Ensure the layers closed on the profile of the study area. Thebasic principles of "cyclicity recession compare and hierarchical control", and themethod of descending gradually to control and comparison by level are applied insub-layer comparison. By the control of marker bed, the third cyclicity recession wasused to divide and compare sandstone groups and the forth cyclicity recession wasused to divide and compare single-layer, thus, to determine the stratigraphicrelationship of each single monolayer and the monolayer of adjacent wells. The Ireservoir group of Nantun second formation was divided into10sub-layers and IIreservoir group was divided into12sub-layers, a total of22sub-layers.Basing on core data combined with well logging and comprehensive loggingdata, we study the deposition types and distribution characteristics of the Nantunsecond formation. And on the basis of a production performance, the reservoirevaluation is made, so that the distribution of favorable reservoir and oil and gas canbe predicted, which provides a foundation for the oil field adjustment. Moreover, onthe basis of the previous sequence stratigraphic research, combining the core, loggingand seismic data of Nantun second formation of Bei301block, according to the basic theory of geology and sedimentology, the principle of sequence stratigraphy, loggingprinciple, structural geology, petroleum geology, check the sub-layer division of oilwells in the study region well by well and layer by layer, adjust the unreasonablestratification. As a result, a more reasonable phased-stratigraphic correlationframework is established, which has provided a foundation for the sedimentarysystem research.By comparing electrical properties of reservoir rock of Nantun group, geologicalphase and logging facies analysis of the core and facies models are established.Sedimentary micro-phase of the single well is determined and the flat distributioncharacteristics of sedimentary microfacies are analyzed. Then sedimentarymicro-phase and the flat distribution characteristics of sedimentary microfacies ofNantun group are summarized. Sedimentary facies can be divided into fan-delta plainsubfacies, the front edge facies, front delta subfacies and shallow lake subfacies,underwater distributary channel microfacies, underwater distributary channelmicrofacies underwater distributary river mouth dam microfacies, microfacies of thefront sheet sand and shallow lake dam deposition micro-phase.