The Comprehensive Evaluation Of Chang 6 Reservoir Banqiao — Heshui Area

Banqiao-Heshui area is located in the southwestof Yishan slope in the Ordos basin, the total area of the study is about 5700km2.Currently, the Chang 6 reservoir of Yanchang Formation of Triassicisthe main oil-bearing formationin oilfield development. The characteristics of the Chang 6 reservoir in Banqiao-Heshuiarea has low porosity, low permeability, low oil saturation, belongs to the typical "three low reservoir". Thedeep-semi deep lake facies is themainlysedimentary faciesof The Chang 6 reservoir. Because of the whole areaof Banqiao-Heshui has influenced by the southwest and north east material source, the differences ofeffect degreeof material source created the presentcharacteristics of sand body distributionof Chang 6 reservoir in Banqiao-Heshuiarea. In this paper, through the investigation and combined with previous research, for the more than 400 wells of the small layer has been contrasted and divided. Using the data of the core photos, the cast thin section, the scanning electron microscope, the particle size analysis etc., comprehensively studied the characteristics of sedimentary facies, tectonics and petrology characteristics in study area. By theexperiment of the high pressure mercury injection, theconstant velocity mercury injection, the oil and water phase permeability, the NMR, realizedthe process of the reservoir micro pore structure and seepage mechanism from qualitative description to quantitative characterization. Established a series of relations betweenthe reservoir lithology and the property,the porosity and the permeability, the property and the oiliness, the propertyand the electric properties. Based on the above, starting from the geological characteristics, reservoir microscopic pore structure characteristics, microscopic seepage characteristics, local micro structures etc., various factors that influence the reservoir physical property were analyzed. Extracted a series of representative parameters from thephysical parameters, the microscopic pore structure parameters and the permeability characteristic parameters,implementation the division of the reservoir and the comprehensive evaluation by the Q type clustering method of SPSS. The reservoir from good to bad has divided into four categories, and the reservoir evaluating comprehensive parameters table of various parameters has established, screening the advantage reservoir distribution area, providing a strong basisfor the next step of oilfield development and increasing reserves and production.