Research On Sand Body Description Method Of Front Subfacies Of The Putaohua Oil Layer In Typical Block, Sanzhao Depression

Putaohua reservoir is mainly controlled by the large river and delta sedimentary systemin northern and the front subfacies sand body develop. Reservoir physical property graduallybecome worse from north to south.The thickness of single sand body is thin, and that thininterbeds developed in the Yongle oilfield and Zhaozhou oilfield.Lateral sand body ofsedimentary facies changes quickly.Reservoir heterogeneity is strong.So prediction effect ofinterwell sand body is bad just rely on the traditional experience and subjective understanding.It’s difficult to meet the needs of fine exploration in the development phase. So applywell-seismic integration to achieve quantitative characterization of distributary channelboundary and accurate prediction of interwell sand body, which has become a problem to besolved that about sand body quantitative description of the front subfacies.This study takes the seismic sedimentology theory as the core content. In combinationwith seismic data and well data as technical route, With high vertical resolution of loggingdata as constraint condition, to predict distribution of interwell sand body by seismic attributeanalysis and seismic inversion. To describe space distribution of sand body by the means ofcomputer3D visualization technology. Study on sedimentary model of sand body and dissectsingle sand body carefully. Research distribution regularities of sand body to display the realappearance of reservoir. Deepen sedimentary microfacies and reservoir distribution and figureout how sand body develop in the work area, which provides the basis for interwellencryption adjustment and development measures.This study selected125wells in the Yong56-96block in the northeast of Yongle oilfield.Carry out seismic attribute analysis and well combined seismic inversion to completequantitative characterization of underwater distributary channel sandbodies, increasing theprediction degree of interwell sand body. By the comprehensive analysis, the continuity ofchannel sand body gets better in the study area; River branchs and the single channel in thesedimentary units increase. The distribution of interwell sand body become more accurate. Asa result, complete the fine description of sedimentary facies belt. At the same time combinedwith anatomy of single sand body of203wells in the Zhou6block, Zhaozhou oilfield,establish a depositional model of single sand body. We eventually establish four kinds ofdistribution pattern of single sand body that developed in the underwater distributary channel.That is "dendritic type、woven mesh type, single continuous type, residual intermittenttype"..Set up offshore spill type, far shore flowing type, burst flood type, channelcross-bridge type, inertial lamellar flow type, inertial stripe type" six distribution patterns ofsingle sand body in the front sheet sand.Apply quantitative description of sand body combination to build the structure types ofplanar and vertical sand body. and find out the sand body heterogeneity of front subfacies.According to the sandstones’ thickness, fine stratigraphic comparison, the nuances of loggingcurve, change trend of the sand body thickness, development pattern of the pinchout area, etc, we research front subfacies thin reservoir and sand sheet each sand body、Boundary andconnected condition. To explore quantitative description methods of sand body in the frontsubfacies.