中国中西部前陆冲断带构造变形与油气成藏模式

Tectonic deformation and hydrocarbon accumulation model of foreland thrust belts in central and western China

为了明确中国中西部前陆冲断带的构造变形特征和油气成藏模式,在中、新生代区域构造背景分析的基础上,根据空间构造格局的叠加和变异以及时间上构造发展的连续和叠加特征,将中西部前陆冲断带的构造变形分为叠加型、改造型和原型3类。构造变形制约着油气成藏环境的演变和油气的聚集与分布,通过对库车、四川盆地西缘和柴达木盆地北缘等前陆冲断带的典型油气藏成藏过程分析,认为中西部前陆冲断带具有3种成藏模式,即叠加型冲断带的多期成藏以晚期为主模式、改造型冲断带的早期成藏和晚期调整模式、原型冲断带的晚期原生聚集及改造次生成藏模式。

In order to understand tectonic deformational characteristic and hydrocarbon accumulation model of foreland thrust belts in cen-tral and western China,regional tectonic settings in Mesozoic-Ce-nozoic were analyzed. According to the stacking and variation of tectonic styles in space and the continuance and overlapping of tectonic evolution in time,the tectonic deformation of the fore-land thrust belts can be divided into three types of superposition,reformation and prototype in the central and western China. Tec-tonic deformation controls ihe evolution of reservoir-forming set-tings and the hydrocarbon accumulation and distribution. The a-nalysis of some typical petroleum accumulation courses in west-ern edge of Kuchem,Sichuan and northern Qaidam Basin shows that there are three hydrocarbon accumulation models in the fore-land thrust bells in central and western China; multi-stages hy-drocarbon filling and late accumulation in superposition foreland thrust belts,early petroleum accumulation and late adjustment in reformation ones,late primary accumulation and secondary reser-voirs formation by reformation in prototype ones.