川西须家河组超致密砂岩成岩作用与相对优质储层形成机制

川西须家河组砂岩是我国重要的天然气储层和产层,同时也是我国埋藏深度最大和最为致密的碎屑岩储层之一,在其超致密背景下发育有对天然气聚集有利的相对优质储层.须家河组砂岩埋藏后经历了复杂的成岩作用,相对优质储层中次生孔隙与原生孔隙并存.本文基于对川西须家河组超致密砂岩的岩石学、矿物学、地球化学和其它储层特征研究,总结了川西深埋藏条件下须家河组砂岩的成岩作用特征及其相对优质储层的形成机制.

Ultra-tight sandstone diagenesis and mechanism for the formation of relatively high-quality reservoir of Xujiahe Group in western Sichuan

Xujiahe sandstone in west Sichuan of China which is not only the important gas reservoir and producing pay, but also the one of the most deeply buried and tightest clastic reservoir rock has developed relatively favorable reservoirs for natural gas accumulation. After burial, this sandstone has experienced a complex change in the process of diagenesis, so that the secondary porosity and primary porosity coexisted in it. Bsed on the study of petrography, mineralogy, geochemistry and characteristic of diagenesis of this sandstone reservoir, we generalize the reservoir diagenetic features of Xujiahe sandstone in west Sichuan in the condition of deep burial, and then, conclude its formation mechanism of relatively high quality reservoirs.