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石油体系目前正被纳入板块构造的基本格架进行研究。这种新的研究方法导致了沉积盆地动力学演化过程中三类石油体系的确定。这三种石油体系是“初始裂谷型”、“大陆地台型”和“造山带—三角洲型”。一个含油气盆地的油气富集度和效率通常取决于这三类石油体系中的任意二者,也许是全部三者之间的组合。前陆盆地也许是最好的例子。板块构造理论认为,活动性的岩石圈是毋庸置疑的,且毫无例外。由于岩石圈的水平或垂向位移,流体和物质两者在沉积盆地内可能发生转移。因此,石油体系看来是地壳活动的直接产物。当油气从源岩中排出后,它们可能在另一个岩石单元中分散并通过渗漏而消失于大气圈中,或者被一些渗透屏障圈闭起来。在后一种情况下,所产生的油气聚集被看作一种暂时的富集,它的持续时间基本上取决于进入的流体流动强度和渗透屏障的封阻能力。全球性地质动力学格架内任一特定石油体系的研究能够对有争议的含油气区域的富集度(或其反面)进行评价。
The petroleum system is currently being studied in the basic framework of plate tectonics. This new research method led to the determination of three types of petroleum systems during the evolution of sedimentary basins. The three petroleum systems are “initial rift type”, “continental platform type” and “orogenic belt - delta type”. The hydrocarbon enrichment and efficiency of a petroliferous basin usually depends on any two of these three petroleum systems, perhaps a combination of all three. Foreland basins may be the best example. Plate tectonics theory suggests that the active lithosphere is beyond doubt and without exception. Due to the horizontal or vertical displacement of the lithosphere, both fluid and matter may migrate within the sedimentary basin. Therefore, the petroleum system appears to be a direct product of crustal activity. When hydrocarbons are expelled from the source rocks, they may disperse in another rock unit and disappear into the atmosphere by seepage or trapped by some seepage barrier. In the latter case, the resulting hydrocarbon accumulation is considered as a temporary enrichment and its duration is essentially dependent on the fluid flow into the fluid and the barrier capability of the permeable barrier. Studies of any particular petroleum system within a global geological kinetic framework can assess the degree of enrichment (or the opposite) of a contested hydrocarbon-rich region.