Shanxi Formation In Daniudi Gas Field And The Distribution Of Sedimentary Facies And Lithofacies Study

Daniudi fields in Ordos Basin was located in Tabamiao area in the northeast of Erdos Basin. Tectonic position is in Yishanslope a gentle structre contained a little fault, of the tight sand reserior and having the strong heterogeneity. In this paper, sedimentology and lithofacies palaeogeography of the guide, based on drilling core, well logging data, Shanxi Formation of daniudi gas field in Ordos Basin as the research object,through single well stratigraphic classification, the Early Permian Shanxi Formation of Daniudi gas field is divided into P1s1 and P1s2, and from botton to top it Could be further divided into Shanxi Formation 1-1, Shanxi Formation 1-2, Shanxi Formation 1-3, Shanxi Formation 2-1, Shanxi Formation 2-2, Shanxi Formation 2-3 six small layers.Based on lithofacies identification chart’ establishment, system researched Shanxi Formation 1-1, Shanxi Formation 1-2, Shanxi Formation 1-3, Shanxi Formation 2-1, Shanxi Formation 2-2, Shanxi Formation 2-3 six small layers’ distribution of rock phase plane. Through drilling core’s observation, well logging data’ analysis, established Shanxi Formation rock Color, lithology, sedimentary tectonics, biomarker, grain size probability curve, log facies profile structure etc sedimentary microfacies identification marks.Based on above-mentioned research of sedimentary microfacies identification marks, the Shanxi Formation of Daniudi gas field is divided into delta plain facies, and it could be further identified the distributary channel, depression, natural levee, crevasse splay, peat bog and interdistributary bay etc sedimentary microfacies, and system researched all kinds of sedimentary microfacies characteristics. Based on the sedimentary microfacies of single well and sedimentary micro contrast research between drilling, system mapped the plane distribution of sedimentary microfacies of the Shanxi Formation all small layers of Daniudi gas field. Researched its planar distribution and vertical evolution characteristics, ultimately established the depositional model of sedimentary period development of Shanxi Formation.