金属矿床和油气藏:沉积盆地中的两个亲兄弟

越来越多的证据揭示,沉积盆地中的很多金属矿床之中及附近发现有油气显示和沥青残斑,甚至油气藏。沉积盆地中的大多数金属矿床的流体包裹体中检测到甲烷和乙烷等有机气体,甚至一些矿床包裹体中还检测出原油。反过来,在很多油田的原油中也发现高含量金属元素。然而,长期以来,大多数研究者对沉积盆地金属矿床或者油气藏的研究是孤立进行的。文章对沉积盆地中金属矿床与油气藏这两个看似风马牛不相及的地质体进行了空间关系、物质关系和时间关系的分析,结果认为盆地中上述地质体的形成是对统一地质事件的响应,即在构造应力或者岩石静压力驱动下,成矿流体和油气向沉积盆地的隆起以及其他有利部位运移并成藏成矿。该认识对沉积盆地中金属矿床和油气藏的勘查也有指导意义。

Metal deposits,oil and gas reservoirs: two brothers in sedimentary basin

More and more evidences revealed that a large number of asphalt remnants or oil and gas reservoirs were found in the metal deposits. Meanwhile organic components such as methane and ethane were detected in fluid inclusions of the metal ore. Even oil were detected from some fluid inclusions on metal deposits. And high content of metal elements were also identified in oil. Nevertheless, for a long time, most researchers have separately studied metal deposits or oil and gas reservoirs in sedimentary basins. In this study, the spatial, genetic and temporal relationships between metal deposits and oil and gas reservoirs in sedimentary basins are discussed. It is considered that the formation of the above-mentioned deposits in the basin was a response to the same orogenic event. Under tectonic stress, ore-forming fluids, oil and gas migrated along higher permeable pathways (e.g., fault, unconformity and rock) in sedimentary cover and later oil-gas reservoir and ore deposit are successively formed in uplift position and other traps. This understanding is also a guiding to the exploration of metal deposits and oil and gas reservoirs in sedimentary basins.