弧后走滑拉张盆地油气资源潜力巨大已被广泛认识，本文通过对缅甸马达班湾盆地东部天然气碳同位素特征分析，结合该区块弧后走滑拉张盆地大地构造背景、油气地质条件等以探讨指导该区油气勘探的重点方向。认为：本区浅层天然气的组分与碳同位素值表现为较明显的热成因气为主、生物气为辅的特征；本区中深层天然气中CO2表现为无机成因气来源的碳酸盐岩热分解形成为主，底辟及热流体上侵是导致这种热分解形成的条件，并促使了该区中深部层段对应的大量烃源岩热演化进入生烃门限，从而生成大量油气，并在具备相应适合的储盖条件下运移成藏。所以该区中深层段应为本区油气勘探与开发的主力目标层段。%It is well known that lots of petroleum is in back-arc strike slip and extension basin, according to natural gas carbon isotope data from the Moattama Bay basin which is back-arc strike slip and extension basin geotectonic setting in Myanmar, integrating with the geotectonic setting and petroleum geology conditions et al to find the evidences to guide petroleum exploration in this study. In this case, components and carbon isotope data of shallow layer natural gas in the block demonstrate that thermogenic gas is major and biogas is a little. CO2 components of natural gas in deep zones show a major carbonatite thermolysis characteristic which is inorganic origin in this block. For this thermolysis, diapirs and thermal fluids make an important role which has a help to achieve oil threshold for the corresponding source rocks of deep zones at the same time, much petroleum is generated and migrated to the favorable intervals which have a good reservoir and cover conditions. So the middle-deep zones in this block are the major perspective for exploration and exploitation of petroleum.
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