塔里木盆地轮古西地区断裂对奥陶系古岩溶的控制作用

轮古西地区发育众多断裂,可分为一、二、三级,性质主要为逆断层,走向以北东-南西向为主.断裂对古岩溶地貌的形成和发育具有明显的控制作用,其中轮西断裂和轮古9断裂两条一级断裂主要控制了古岩溶宏观地貌:轮西断裂以东地区为古岩溶高地,以西为古岩溶斜坡;轮古9断裂以东至轮西断裂地区为峰丛洼地地貌:以西主要为峰林谷地地貌.二、三级断裂主要控制了古岩溶微地貌的发育,地表古水系和暗河常沿着这些断裂发育,呈近南-北向、北东-南西向展布.各级断裂带附近古岩溶储层尤为发育.轮古41北断裂群、轮古9西南断裂群、轮古40东断裂群以及轮古15井区断裂群是古岩溶储层的有利发育区.

CONTROLLING EFFECTS OF FAULTS OVER PALAEOKARST IN WEST LUNGU REGION, TARIM BASIN

Many reverse faults, mainly NE-SW directional, develop in west Lungu region. The fault systems can be divided into three orders. Which shows that the faults control the formation and development of palaeokarst landform. The first-order faults-Lunxi fault and Lungu No.9 fault- mainly control the palaeokarst macro-landform. The eastern area to Lunxi fault is palaeokarst highland and the western palaeokarst slope. In palaeokarst slope, the eastern area to Lungu No.9 fault is Fengcong-depression and its western area is Fenglin-valley. The lower-order faults controlled palaeokarst micro-landform. The palaeo-surface water systems and underground river usually develop along these faults in near SN and NE-SW direction. Palaeokarst reservoir especially develop well around these fault systems, which indicates that the faults control the development and distribution of palaeokarst reservoir. The area of north Lungu No.41 fault-group, west Lungu No.9 fault-group, east Lung No.40 fault-group and Lungu No.15 fault-group are favorable for the development of palaeokarst reservoir.