Research On The Favorable Reservoir’s Dominated Factors Of The Triassic Chang-6Oil Formation In Zhongshanjian Area, Jingbian Oilfield

In this paper, using sedimentary petrology, reservoir geology, logging geology and the otherrelated theory as the basis, combining well logging, logging, cast thin section，scanningelectron microscope, core analysis data. And the sedimentary facies types, spatial distributionof sedimentary microfacies, reservoir lithology characteristics, diagenesis，physical propertyand storage space weer researched meticulously. On these bases, we made a comprehensiveevaluation of the reservoir, the favorable reservoir was selected. And from the comprehensiveangles of deposition and diagenesis, we analyzed the dominated factors of the favorablereservoir.The sedimentary facies type of Chang-6reservoirs of Yanchang formation in ZhongshanjianArea of Jingbian oil field is delta plain, the reservoir is mainly distributed in the distributarychannel sand body, low to extremely low permeability, medium heterogeneity. Diagenesistypes are diverse, pore structure is complex and the distribution is uneven. Favorable reservoiris mainly controlled by sedimentation and diagenesis. If a relatively high porosity andpermeability reservoir developed in a generally low porosity and permeability background,which should be the favorable reservoir, it’s a relative conception. Depositional environment isthe forming foundation of the favorable reservoir, il controls the reservoir rock types, clasticconstituents, internal structure, ctc. Diagenesis affects the ’reservoirs physical propertytransformation, it have both damaging and constructive effects, directly affects pore evolution.Strong compaction, late siliccous cementation, ferroan calcite and ankerite cementation, whichall lead to the reservoir’s physical property damaged seriously, but the later dissolutioneffectively improve the reservoir’s physical property, therefore diagenesis is one of the mainfactors that dominate the favorable reservoir. Combining the oil sources、sandstone thicknessand reservoir physical property character to put forward the favorable exploration area ofChang-6formation reservoirs, these above provide evidencics for the futrher exploration andexploitation.