Study On The Sedimentary Microfacies And Sand Body Structure Of The Putaohua Reservoir In The Northeast Of The Weixing Oil

The Weixing oilfield is located in the connected region of Daqing Changyuan and the Sanzhao sag,spanning two two-order tectonic units.The whole structure is characterized by the slope area ascending to Changyuan.The Putaohua Reservoir is one of the main oil layers in the Weixing oilfield.The Putaohua Reservoir is a section of the Cretaceous Period Yaojia Formation.Based on the logging data,core data and 3D seismic data of 273 wells in the study area,21 sensitive seismic attributes are extracted and optimized according to the relevant techniques of Random Forest and data mining.The machine learning sample set is constructed.The 13-layer sedimentary microfacies diagram is predicted by fuzzy discriminant method.At the same time,in the vertical direction,the sand body structure is studied by analyzing the logging facies and the logging response characteristics of different sedimentary microfacies are summarized.The sand body characteristics and distribution of Putaohua reservoir in the study area are studied.In this paper,from quantitative identification to qualitative interpretation,we identification two types of sedimentary facies,six microfacies,and three main sand bodies.The sedimentary environment in the study area is from water to water and back to water.The PI11-PI2 layers and the PI7-PI9 layers are delta front facies,mainly developing two types of isolated river channel and Sheet sand connected channel.The PI3-PI6 layers are delta plain facies,mainly developed two types of isolated river channel and vertical additive channel.In this paper,the combination of quantitative and qualitative methods has a certain breakthrough compared with the traditional research methods.It further improves the ability of vertical and plane morphological characterization of microfacies,and improves the applicability and accuracy of the analysis.It provides a good geological basis for the subsequent well location deployment.It provides new methods and new ideas for microfacies research.