塔里木盆地克深气田构造裂缝主控因素及发育模式OA

The Keshen Gas Field,a typical representative of ultra-deep tight sandstone reservoirs in the Kuqa Depression,exhibits a fracture system whose development characteristics and distribution patterns exert a critical control on efficient natural gas development.Based on core and imaging log data,this study systematically characterizes the genetic types,orientation,filling properties,and aperture of structural frac-tures within the Keshen Gas Field.It analyzes the patterns of structural fracture development,identifies the main controlling factors,and establishes a developmental model applicable to ultra-deep tight sandstones.The results demonstrate significantly different controlling mechanisms for fracture development across various blocks:fractures in the northern block are primarily controlled by weakened tectonic stress intensity and the modification by early fracture fillings,resulting in a relatively lower fracture density.The central block,located in the anticlinal core and a stress superposition zone,possesses favorable conditions for fracture ini-tiation and propagation,including high rock brittleness and thin mechanical layers,making it the most intensely fractured area.In the southern block,efficient stress transmission due to thinner salt-gypsum lay-ers,combined with strike-slip activity and anhydrite cementation support,gives rise to fractures character-ized by large apertures and low filling degrees.The established fracture development model reveals a"tectonic-sedimentary"binary coupling control mechanism,enriches the understanding of fracture forma-tion mechanisms in ultra-deep tight sandstones,and provides theoretical support for optimized well place-ment,hydraulic fracturing design in the Keshen gas field,as well as for the exploration and development of fractured reservoirs in similar structural settings.