中亚地区与中国西部盆地类比及其油气勘探潜力

A Comparison of the Basins in Western China with Those in Central Asia and the Oil-Gas Exploration Potential of Western China

中国西部盆地和中亚某些含油气盆地在地质背景和石油地质条件等方面有一定的相似性 ,从盆地结构上看 ,中亚地区的盆地与中国西部盆地大多为具有不同构造属性的构造阶段 ,相互叠置的叠合盆地 ;从烃源岩发育特征来看 ,中下侏罗统的含煤岩系使中国西部与中亚地区烃源层有较好的可比性。勘探实践证明 ,无论在中亚还是在中国西部该含煤岩系是最重要的烃源层之一 ,但中国西部绝大多数盆地广泛发育古生界烃源岩 ,这无疑大大增强了中国西部盆地的生烃潜力。从储集岩特征来看 ,中亚地区含油气盆地以发育中—新生界储层为主 ,而中国西部大部分盆地不仅广泛分布中—新生界储层 ,具有发育古生界储集层的优势 ;从资源类型来看 ,中亚地区以天然气占有绝对优势 ,而中国西部除天然气外 ,石油资源也有良好的勘探前景。总的来看 ,中国西部的油气勘探潜力要优于中亚地区的大多数盆地。

There exist some similarities between the basins in western China and those in Central Asia in geological structures and oil gas conditions, but their differences remain obvious. In basin structure, both are composite basins, with different structures formed in different evolutionary stages. In source rock, there exists Jurassic source rock in all of the basins, but Palaeozic source rock is only present in basins of western China. In reservoir, there is mainly Mesozoic Cenozoic reservoirs in basins of Central Asia, but basins of western China have not only Mesozoic Cenozoic reservoirs but also Palaeozic reservoirs. In type of resource,the Central Asia basins possess mainly natural gas, whereas the western China basins have both oil and gas. It is therefore concluded that the basins in western China have better oil-gas conditions and petroleum prospects as well as greater exploration value than those in Central Asia.