变质岩野外风化壳特征及储层随钻评价OA

In order to research the zoning characteristics,fracture development characteristics and reservoir evaluation of the weathering crust of buried hills,the metamorphic rock weathering crust outcrop in Xinglong,Hebei was selected as the research object.First,by analyzing the physical and chemical characteristics and fracture development characteristics of different parts of the weathering crust,it was divided into four zones:clay zone,sandy conglomerate zone(weathered sandy conglomerate zone+transport sandy conglomerate zone),weathered extremely fractured zone,and weathered leaching zone.It derived a zoning method for metamorphic rock weathering crust based on clay mineral content,rock slice,and element content.Secondly,by analyzing the heterogeneity of fracture development,the relationship between fracture development and lithology,and the relationship between fracture inclination angle and effective space inside the fracture,the development rules of dominant fractures are obtained:inside light-colored rock,near large faults,high-angle fractures with some distance away from the clay layer on top of the weathering crust.The reservoir evaluation steps during the drilling process based on the field weathering crust research and well data were established:weathering crust zoning based on drilling cuttings,elements,and engineering parameters;quantitative evaluation of light-colored rock based on continuous statistics of drilling cuttings color index and Light-Colored Mineral Index;fracture recognition based on drilling cuttings and its slice,mechanical specific energy(MSE),and gas logging.