黄海新生代构造及油气勘探前景

黄海构造是地质领域重要的研究课题,尤其是南黄海油气勘探工作虽然经过了30多年的研究与勘探,但至今仍进展不大;因此,如何突破该区油气勘探的难题引起普遍关注。黄海地区在新生代经历过2次近南北向的缩短与挤压(135~52 Ma,23~0.78 Ma)和2次近东西向的缩短与挤压(52~23 Ma,0.78 Ma—)。新生代的4个构造期对于油气资源的形成、运移和保存产生了重大的影响。白垩纪—古新世是形成盆-山体系的雏型时期,始新世—渐新世(52~23Ma)是生油层形成的主要时期,中新世—早更新世(23~0.78 Ma)的构造作用使NNE向的先存断裂成为油气运移的良好通道,中更新世以来(0.78 Ma—)近东西向的挤压使NNE向的断层闭合,为油气的保存创造了良好的条件。建议大力加强南黄海地区NNE向的先存断裂与古近系相交部位及其上部的油气勘探工作。

Cenozoic Tectonics of the Yellow Sea and Its Oil-Gas Exploration

To study the tectonics of the Yellow Sea is the common concern project.Although the oil-gas exploration has undergone more than 30 years in South Yellow Sea,the exploration progress of that is not successful.There are two nearly N-S trending shortening and compression epochs(135-52 Ma and 23-0.78 Ma) and two nearly E-W trending shortening and compression stages(52-23 Ma and 0.78 Ma-) at the Yellow Sea and its adjacent areas during Cenozoic.Four tectonic epochs during Cenozoic have important influences on forming,migrating and preserving oil-gas reservoirs.An embryonic form of the basin-range framework occured in Cretaceous and Paleocene(135-52 Ma),and Eocene-Oligocene(52-23 Ma) is the main forming epoch for oil-gas source.During Miocene-Early Pleistocene(23-0.78 Ma),tectonism caused favorable passage for oil-gas migration along NNE trending faults.Since Middle Pleistocene(0.78 Ma-) the NNE trending faults are closed and make a good condition for reservation of oil-gas,controlled by E-W trending shortening.The authors suggest to pay more attentions to the oil-gas exploration at the intersections between NNE trending existing faults and Eocene-Oligocene systems,and also pay attentions to the upper parts in South Yellow Sea area.