塔里木盆地中部泥盆系东河砂岩成岩序列与储集性能控制因素?

根据对岩石铸体薄片和阴极发光薄片、地层厚度、古地温梯度以及镜质体反射率等资料分析研究认为：塔中地区东河砂岩经历了压实作用、粘土胶结、石英次生加大、碳酸盐胶结、溶蚀作用、自生高岭石沉淀等多种成岩作用，目前已经达到了晚期成岩阶段。这些成岩作用在塔中4井以东和以西的地区存在较明显的差异，西部进入早成岩阶段B期和晚成岩阶段A期的时间较早，成岩演化程度较高，且具有下部溶蚀上部胶结的分带性；而东部则反之。优质储层主要分布于颗粒成分较纯、泥质含量较低、构造位置上长期处于高部位、被油气充注，但未被晚期碳酸盐胶结的地区。即二叠纪以来长期处于构造高部位的前滨-临滨相带内。

DIAGENESIS AND CONTROLLING FACTORS OF RESERVOIR QUALITY OF DEVONIAN DONGHE SANDSTONES IN CENTRAL TARIM BASIN

The diagenetic process,porosity evolution,factors controlling reservoir quality,the time and duration of entering and undergoing each diagenetic stage of the Donghe sandstones in central Tarim Basin are studied. The relative primary and secondary porosity volume is obtained from microscopic measurement. According to the regional structural evolution,the factors controlling solution are discussed. Combined with the hydrocarbon filling and escaping history,the factors of secondary porosity surviving and disappearing are analyzed. The results indicate that the Donghe sandstones in central Tarim Basin went through the compaction,clay cementation,quartz overgrowth,carbonate cementation,solution and authentic kaolinite precipitation during the diagenesis,and now it is in the late diagenesis stage. There are some differences in diagenesis between the east and the west areas. In the west area,the Donghe sandstones entered the early diagenesis B and late diagenesis A earlier than in the east,and is with a clear lower solution-upper cementation sequence section. The good reservoir is mainly distributed in the places with pure lithological components,low clay,continuing uplifting,early hydrocarbon filling,and no carbonate cementation. That is the foreshore-shoreface area which has been uplifting since the Permian.