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表生岩溶与埋藏溶蚀是碳酸盐岩储层发育的最重要成岩作用,两者受岩石等内在因素的影响基本相同,但所受的外部主控因素差异显著。表生岩溶受构造不整合面、古构造等影响较大;埋藏溶蚀主要受断裂与深部流体控制。表生岩溶主要表现为垂向分带性明显的复杂孔洞缝网络结构,而埋藏溶蚀主要呈受断裂—裂隙控制的“V”形洞穴样式或与断裂有关的阶梯状分布。表生岩溶发育一些标型特征,如钙质壳,古土壤,铝土矿,淡红色方解石晶体,溶蚀沟、坑、天坑,新月形状、悬垂和纤维状渗滤砂或胶结物,岩溶角砾及与地下暗河有关的机械流水沉积;埋藏溶蚀往往发育与中低温热液有关的异形铁白云石、萤石、闪锌矿、磁黄铁矿等密西西比河谷型矿物以及塌陷构造、裂隙结构、不规则的角砾(化)岩体等。塔里木盆地塔北地区主要发育表生岩溶作用;塔中地区西北部不具备发育大规模表生岩溶的地质条件,以发育埋藏溶蚀作用为主。
Superficial karstification and burial dissolution are the most important diagenetic processes for the development of carbonate reservoirs. Both are affected by the internal factors such as rock, but the external control factors are significantly different. The epikarst karst is greatly influenced by structural unconformity and paleotectonics. Buried dissolution is mainly controlled by faults and deep fluids. The epikarst karstification is mainly characterized by the vertical zonation of complex pore network structure. The burial dissolution mainly consists of the “V” shaped cave mode controlled by fracture-fracture or the ladder-like distribution related to fracture. Some phenotypic features are developed in epikarst, such as calcareous crust, paleosol, bauxite, pink calcite crystals, dissolution trenches, pits, trenches, crescent shapes, drape and fibrous percolation sand or cements, karsts Breccias and mechanical flow-related sediments associated with the underground underground river; Buried dissolution often develops mesocarbon-type minerals such as deformed iron dolomite, fluorite, sphalerite and pyrrhotite associated with medium- and low-temperature hydrothermal fluids, as well as collapsed structures, Structure, irregular breccia () rock and so on. The Tabei area in the Tarim Basin mainly develops supergene karstification. The northwestern Tarim Basin does not have the geological conditions for the development of large-scale epikarst karstification.