裂缝对塔中奥陶系碳酸盐岩储集层岩溶发育的控制

碳酸盐岩储集层主要受沉积、成岩、构造及岩溶的控制,非均质性极强,其中裂缝对碳酸盐岩储集层的改造至关重要。通过对岩心、成像测井溶蚀孔洞识别和裂缝统计,对比不同裂缝发育强度、不同产状裂缝与岩溶发育之间的关系,发现溶蚀孔洞与裂缝密切共生,不整合面下的高角度裂缝对风化壳岩溶的发育具有重要的促进作用,而低角度裂缝与埋藏期岩溶作用有很好的对应关系。这为利用不同产状的裂缝发育特征进行岩溶-裂缝型储集层的评价与预测提供了新途径。

The Control of Fractures on Karst in Ordovician Carbonate Reservoirs in Tazhong Area, Tarim Basin

As controlled by sedimentation, diagenesis, structure and karst, carbonate reservoirs are strongly heterogeneous and it is important for fracture to rebuild carbonate reservoirs. Through observation over cores, dissolution caves with FMI logging, statistics of fractures, correlation analysis of the fractures vs. karstification, it is found that fractures are closely accreted with karstification and the high angle fractures under unconformity surface have a great promotion on the development of weathering crust-type karst, while low angle fractures have perfect correspondence to burial karstification. This affords a new revelation to evaluate and predict karst-fractures-type reservoirs by the characteristics of fractures in different occurrences.