塔里木盆地麦盖提斜坡构造演化及油气地质意义

为分析塔里木盆地麦盖提斜坡的有利成藏条件,并提出下一步有利区带和部署建议,从地震和钻井资料入手,运用叠合盆地构造解析方法,在动态分析麦盖提斜坡形成过程的基础上,分别研究了东、西两段的构造带特征与成因,并阐述其油气勘探意义.研究认为,多期构造演化与东西差异演化是东、西两段油气成藏条件、运聚背景和重点勘探层系明显不同的关键.西段处于斜坡背景上的海西晚期构造带,保存条件好,与断裂紧邻的上倾方向的上古生界岩性体是控制油气成藏与富集的关键因素.斜坡东段位于和田古隆起,玉北1井区构造处于加里东中、晚期与海西晚期的构造应力叠加区,更有利于奥陶系岩溶缝洞型储层的发育.玉北1井东部潜山带下奥陶统暴露区上覆一定厚度的地层,对溶蚀孔、洞、缝的有效保留更有利,也值得选择性探索.

Tectonic evolution and its petroleum geological significances of the Maigaiti Slop,Tarim Basin

In order to analyze the favorable conditions of hydrocarbon accumulation and identify favorable plays of Maigaiti slop in Tarim basin,we used the tectonic analytical method of superimposed basins to study the cha-racteristics and genesis of the eastern and western segments of the slope and discussed their hydrocarbon exploration significances based on integration of seismic and well data and analysis of the dynamic evolution of Maigaiti Slope.Multi-stage evolution and differential evolution are the key factors causing the obvious differences between the eastern and western segment in respects of hydrocarbon,migration and accumulation conditions and main exploration targets.The western segment in the Late Hercynian tectonic belts has good preservation conditions,and the up-dip upper Paleozoic lithologic body near the faults are key factor controlling hydrocarbon accumulation and enrichment.The eastern segment is located in the Hetian paleo-uplift,where Yubei-1 wellblock is placed in an area with the Middle and Late Caledonian tectonic stress superimposing with the Late Hercynian tectonic stress,providing more favorable conditions for the Ordovician fractured-vuggy reservoir development.The Lower Ordovician exposure in the buried hill zone to the east of Yubei-1 wellblock is covered by a seal of certain thickness which is favorable for the effective preservation of solution pores,vugs and fractures,thus is also a potential exploration target.