东海陆架盆地南部油气资源前景与选区

通过开展二维地震资料调查和重处理,结合钻井、重磁、海陆对比等新老资料开展联合解释认为:东海陆架盆地南部中生界具有分布广、厚度大、沉积中心位于东部,新生界则呈现东西厚中间薄,新生代构造单元中的台北凸起、观音凸起和雁荡凸起上均有中生界分布;白垩系较侏罗系分布更为广泛,侏罗系西部边界为雁荡凸起东侧,白垩系西部边界以瓯江凹陷西侧为界;中生界三口钻井分析结果发现了确凿的海相标志,证实了中生界东海陆架盆地发生多次海侵,结合围区沉积特征认为侏罗纪存在南北向和东西向的海侵,白垩纪主要体现为东西向的海侵;研究区中生界发育中下侏罗统、下白垩统两套烃源岩,新生界发育古新统、始新统、渐新统和中新统四套烃源岩,具有较好的油气资源前景。

Oil and gas potential and target selection in southern East China Sea Shelf Basin

Abstract: Based on the newly acquired and reprocessed seismic data, in combination with drilling data, gravity and magnet inversion and onshore and offshore correlation, the authors studied the geological characteristics of Mesozoic and Cenozoic strata in southern East China Sea Shelf Basin. With sedimentary center in the east, the Mesozoic strata of great thickness are distributed extensively over such uplift areas as Taibei, Guanyin and Yandang. The Cenozoic strata are thicker in the east and west than in the central part in the study area. The southern East China Basin was a marginal depression basin in Mesozoic, with a western boundary of Jurassic on the east side of Yandang uplift, and that of Cretaceous on the west side of Oujiang Sag. More marine facies marks were found in drilling analysis, which shows that the transgression from south to north and from east to west happened in Jurassic, and that from east to west occurred in Cretaceous, in consideration of surrounding sedimentary environments. Source rocks of Lower Jurassic, Lower Cretaceous, Paleocene, Eocene, Oligocene and Miocene are well developed in the study area, so there exists a great hydrocarbon potential in the study area.