南黄海盆地崂山隆起中、古生界断裂特征

The Fracturing Characteristics of Mesozoic and Paleozoic Eras in Laoshan Uplift of South Yellow Sea Basin

近年来,南黄海盆地油气地质调查工作取得了新进展,即发现崂山隆起新近系下伏地层可能为海相地层,但由于勘探程度低等原因,崂山隆起海相地层的分布依然不清。海相地层的残留状况往往与断裂分布有密切关系,因此,探讨崂山隆起中、古生界断裂特征及其控制作用,对于研究海相地层的分布具有重要作用。以新采集的地震资料解释为基础,采用类比方法,探讨南黄海盆地崂山隆起主要断裂带的构造样式和变形特征,确定中、古生界断裂的分布规律。结果表明:崂山隆起主体部分主要发育高角度逆冲断裂,少量分布反转断裂和正断裂;研究区西北部发育由北向南的逆冲断裂,东南部则发育由南向北的逆冲断裂,具有对冲特征;构造变形程度西强东弱。深化了断裂系统对研究区残留海相地层分布控制作用的认识,为深入开展研究区油气调查提供地质构造依据。

The geological surveys for oil and gas in the South Yellow Sea Basin have made new progress recently and found that there might be marine strata below Neogene system of Laoshan uplift, but their distribution remain un clear because of low exploration level. There is a high correlation between the residue status,distribution of marine strata and the distribution of faults in study area. Therefore,in research of Laoshan uplift,the characteristics of Me- sozoic and Palaeozoic faults and their control actions are of significance in further studying the distribution of marine strata. Based on the seismic information newly collected and by using the analogous analysis method, the tectonic style and deformation characteristics of main fracture zones in Laoshan uplift were studied. The results showed that the high angle thrust faults were mainly developed in the main body part of Laoshan uplift and a few reverse faults were distributed. The thrust fractures with north to south direction were developed in the northwestern region of the studied area and the thrust fractures with south to north direction were developed in southeast region. The degree of tectonic deformation in western area is higher than eastern area. These discoveries are helpful to recognize the control action of fracture system on the distribution of residual marine strata, providing a basis of geological structure for intensive exploration of oil and gas in study area.