麦盖提斜坡玛南断裂演化及其油气意义

玛南构造位于麦盖提斜坡的南段,从其发育历史以及原型盆地分析的角度来看,该地区经历了3期构造运动:加里东期、海西期与喜山期,这3期构造控制了区内构造变形与盆地演化。虽然这3次构造运动中区域内奥陶统遭到了不同程度的剥蚀,而且造成了上中奥陶统大面积缺失;但是从玛南断裂带的构造样式以及演化分析来看,该地区在构造运动中也发育了一系列断裂,并且在早期古构造带的基础上,发育起来了继承性很强的现今保存较好的与断层相关的背斜构造。这些断裂带对油气成藏和分布起着至关重要的作用,它不仅可以对早期的油气藏形成破坏,但同时又可以作为油气运移的纽带和桥梁;因此,研究玛南断裂特征,对研究本断裂系烃源岩的成熟度,油气的产生、运移和再运移,以及圈闭的形成都有重要意义。

Evolution and its oil and gas significance in Manan fault of Markit Slope

Manna structure lies in the south of Markit Slope. From the developmenl of history and the angle of the prototype basin analysis, it is considered that this region experiences thine tectonic movements： Caledonian, Hereynian and Himalayan, which control the regional teetonie deformation and basin evolution. Three tectonic movements in this region have caused Ordovician erosion in varying degrees and the absence of the Upper and Middle Ordovician in a large area. But fiom the analysis of structural style and evolution history for Manan fault, the three tectonic movements also develop a series of faults and a strong succession of current well-preserved and fauh-related anticlines on the basis of the early aneient belt. These fauh zones play a vital role for hydrocarbon aceumulation and distribution. It not only can destroy the oil and gas reservoir formed at early stage, at the same time, it can serve as a bridge between oil and gas migration. Therefore, the researeh on Manan fauh has great signifieance for studying the maturity of souree roeks of fauh system, oil and gas generation, migration and re-migration, as well as the fiwmation of traps.