The Research Of Precise Calculation Of Geological Reserves Based On Sedimentary Microfacies

The reserve of oil and gas has always been an important indicator to guide the exploration and development of oilfield, and it’s also the main basis of exploration adjustment in the later stage of oilfield development. So far, Daqing Oilfield has entered high water-cut stage, the phenomenon that geological reserves and cumulative yield does not match is more and more serious, with the deeper development of oilfield. Because of the recognition of sedimentary microfacies is increasing, the unreasonable points in the previous calculation of reserve is becoming more and more obvious. In such situation, we need to refine the calculation of geological reserves, in order to satisfy the current requirement of the oilfield development. So we come up with the research of precise calculation of geological reserves based on sedimentary microfacies.Because of the complex variation of sedimentary microfacies, refer to facies-controlled modeling, the boundaries of sedimentary microfacies are extracted to build sedimentary microfacies gridding data. The attribute value of grid node in sedimentary microfacies is extracted based on the fine geologic research result. Then predict the calculating parameter of grid node, referring to the attribute value of grid node in sedimentary microfacies.Based on the effective thickness of known well, choose the most suitable interpolation method to predict the effective thickness of grid node. Use the reserves per unit volume, predicted effective thickness and control area of grid node to calculate the reserves of grid node. Single well geological reserves is the sum of reserves of all grid node in single well control area. We choose Xingbei development area as study area to analyze the distribution of sedimentary microfacies and physical characteristics based on the fine geologic research. Through the statistics of cored well data in Xingbei development area, the reserves per unit volume of different kinds of sandbody in different layers is figured out. Choose an experimental area as example to calculate geological reserves using new method. Distribution diagram of geologic reserves is easily acquired, so that the distribution characteristics of geologic reserves in the plane can be determined. Comparing the calculation results, the new method is more reliable.