【摘要】 岩溶储层是塔河油田奥陶系碳酸盐岩的主要储层,是海西早期与加里东期岩溶作用的结果。海西期岩溶储层主要发育在石炭系直接覆盖于中下奥陶统之上的地区,上奥陶统覆盖区的岩溶储层主要是加里东期岩溶作用形成的。地震剖面奥陶系反射波组底部上超、顶部削切特征,牙形剌化石带的缺失、志留系层序地层对比均证实奥陶系在加里东中期有过隆升剥蚀,说明塔河油田具备有加里东岩溶作用的地质条件,锶同位素特征证实了加里东期岩溶洞穴的存在。在上奥陶统覆盖区,岩溶储层主要发育于加里东不整合面(T74和T72)下300m之内,岩溶储层中,岩溶洞穴高度主要为0~30m之间,最大可达75m,显然是加里东中期岩溶作用的产物。加里东期断裂控制了加里东岩溶储层的发育,由此预测了加里东期岩溶储层的发育区带。更多还原

【Abstract】 As a result of karstification in early Hercynian and Caledonian, karst reservoirs are the main kind of Ordovician carbonate reservoirs in Tahe oilfield. Karst reservoirs in Hercynian develop mostly in the area where Carboniferous strata directly overlay the mid-lower Ordovician, and the karst reservoirs in the area covered by upper Ordovician were formed in Caledonian. The Ordovician strata had experienced uplift and erosion, which is proven by bottom onlap and top erosion truncation of the Ordovician reflected wave group in seismic section, lack of conodont fossil belt and sequence stratigraphic correlation in Silurian. So, there were geologic conditions for Caledonian karst formation in Tahe oilfield. In addition, the existence of karst cave has been proven by Sr isotope characteristics.!In area covered by upper Ordovician, karst reservoirs mainly develop in the depth less than 300 m under Caledonian unconformity surface. In these karst reservoirs, the height of karst caves is between 0 and 30 m, maximum of 75 m, which shows that the karst caves were distinctly formed by mid-Caledonian karstification. Based on the domination of Caledonian faults on the development of Caledonian karst reservoirs, this paper predicts the development area of Caledonian karst reservoirs.更多还原