活动性强、深部作用活跃——中国沉积盆地的两个重要特点

活动性强、深部作用活跃,是中国沉积盆地,特别是中、新生代盆地的两个重要特点。这由中国大陆本身的结构、动力学演化特征和所处的特殊大地构造位置所决定。如(1)组成中国大陆的诸多前晚元古代陆块面积小,稳定性差;(2)围绕诸陆块的边缘活动带规模大,活动性强;(3)中国大陆在显生宙先后受不同动力学体系的作用和影响,动力学环境多变,演化历史复杂;(4)现今周邻被活动强度和特点明显不同、发展演化历史极为复杂的太平洋 -菲律宾板块、印度板块和西伯利亚等板块所围限,多个方向朝中国大陆汇聚等。以上两个重要特点,通过发生在诸多盆地及邻区的一系列地学现象不同程度地反映出来。如(1)陆内变形强烈而普遍,动力学条件因地而异;(2)构造运动期次多,各期次特征有别;(3)充填速率一般较快,沉积中心多有迁移;(4)后期改造强烈,改造形式多样;(5)岩浆活动频繁,分布广泛;(6)地热场空间不均一,演化高度非线性;(7)岩石圈结构严重不均一,低速、低阻夹层(异常体)发育;(8)新构造运动强烈,今地貌出现尚晚;(9)油气常含有或伴生有多种可能来自深部的气态或液态物质等。这两个重要特点,直接决定着中国沉积盆地的基本性质、总体面貌、演化过程及后期改造特点,造特点,从正、反两方面深刻影响和制约着中国中、新生代陆相和古生代(及中生代和中晚元古代)海相两大类盆地的油气赋存环境、成藏特点、分布规律和资源规模,从而形成了中国陆相盆地油气丰富、海相盆地特征复杂这些与世界总特征截然相反的、显著的中国特色。同时造就了中国沉积盆地的另一个重要特点:后期改造强烈而普遍。

STRONG ACTIVITY AND ACTIVE DEEP ACTION:TWO IMPORTANT FEATURES OF CHINESE SEDIMENTARY BASINS

Strong activity and active deep action are two important features of Chinese sedimentary basins, especially for Meso-Cenozoic basins.These features were determined by texture,dynamic evolution of Chinese continent itself and its special tectonic location.The above two important features were proved by a series of geological phenomenas took place in many basins and the neighboring areas.The features directly determined the basic nature,the total appearance,the evolution process and characteristics of the late stage reformation of Chinese sedimentary basins; deeply affected and restricted oil-gas preservation setting,the characteristics of hydrocarbon pool-forming, distribution regularity and resources scale of China's Meso-Cenozoic continental basins and two types of Paleozoic(Including Mesozoic and Mid-Late Proterozoic)marine basins, thus forming distinct characteristics of abundant oil and gas resources in continental basins but complication in marine basin, which are completely in contradiction with the total characteristics of other areas of the world.