大地电磁测深在下扬子及邻区的应用

全面分析、对比了下扬子及邻区电性层与电性特征。下扬子盆地与周边构造单元的边界及接触关系的研究表明,下扬子盆地基本上为东西对冲结构,东与西均以推覆带形式相接触。建立了下扬子地区岩石圈的层块结构,其特点是各层系间在横向上为隆(薄块)坳(厚块)相间,纵向上为隆坳交替。发现了四条岩石圈级深大断裂,特别是大别—舟山断裂与滨海—桐庐隐伏深断裂是近期研究所得。首次编制出海相中—古生界残留厚度图,并发现了变质岩推覆带下海相中—古生界新领域及火山岩覆盖下海相中—古生界新领域,这些成果为下扬子地区寻找海相油气藏开辟了新的方向。

The Application of MT Sounding in Lower Yangzi and Its Adjacent Area

The stratigraphic electric characteristics in Lower Yangzi and its adjacent area has been completely analyzed and correlated.It is considered that the Lower Yangzi Basin is basically a east-west ramp structure and nappe contact both in the eastern and western boundaries based on the study of Lower Yangzi boundary and its contact with surrounding structures.It is characterized by uplift(thin block) alternating with depression(thick block)laterally and uplift and depression in turn vertically.There are four deep and large lithospheric faults,and two of them,buried deep faults of Dabie-Zhoushan and Binhai-Tonglu,were discovered by recent study.It was the first time that the marine Meso-Paleozoic remnant isopach map was drawn up. Two new marine Meso-Paleozoic prospective areas under both metamorphic rock nappe and volcanic rock are then found.All of these point out the ways for exploring marine oil/gas pools in Lower Yangzi.