The Sedimentary Facies Of Pu Tao Hua Reservoir Of Gu Long South Area

The first member of Yaojia Formation, Putaohua Reservoir of the lower cretaceous, is the study layer in South Gulong Region, locating in southern part of Qijia-Gulong sag of the central depressed area of Songliao basin. Based on the former studies, predecessors’ research, to well logging geology, sedimentology of lake, and lake river fine sedimentology as theoretical guidance, with core observation described as auxiliary, make full use of drilling core, logging and other data, to carry on the study of sedimentary microfacies, has important guiding significance to solve the complicated oil-water relationship in the study area.According to core observation of the research area, combined with the content source, well logging data and other data, building regional skeleton section, thus for stratigraphic classification and correlation, the research is divided into PI upper, PI middle, PI lower and PⅠ1 ~ PⅠ8 small layers. The general characteristic of stratigraphic is thick in northwest and thin in southeast. Through the heavy mineral analysis, ZTR index map and sandstone percentage of comprehensive judgement, the study area are considered to be mainly controlled by the northern provenance, the western material source as a secondary source.Based on color, texture, structure and paleontological facies marks, the research area can be identified into the underwater distributary channel, mouth bar, underwater crevasse splay, distributary bay, sand sheet and far sand dam 6 kinds of microfacies types, and underwater distributary channel with the best connectivity of constitute is the skeleton of putaohua reservoir sand bodies, river mouth bar sand body and sand sheet sand body developed with high frequency but the thickness of the single phase slightly is thin, the connectivity is better, both the north and west are near provenance, with more river channel and larger scale; The sedimentary environment of Gu Long Na putaohua oil layer is given priority to with underwater, mainly for the shore and shallow lake delta front deposition environment, and in the sedimentary period, the overall performance for water body becomes shallow gradually, the water back into the product, to deepen, sedimentary sequence of contraction.