【摘要】 利用矿集区获得的小道距、长排列接收的地震反射初至波走时数据,运用层析成像方法,首次得到长江中下游典型金属矿集区——庐枞火山岩盆地近地表1000m以上的交叉速度结构。各剖面精细的速度结构揭露出庐枞矿集区隐伏的正长岩体顶界面深度与起伏形态,发现岩体顶面凸起及陡变化部位与矿体分布存在着明显的对应关系,罗河铁矿、小岭铁矿、龙桥铁矿、马鞭山铁矿处对应着高速层顶界面的凸起位置。罗河断裂在lz06-1线与lz06-3线表现为明显的横向速度变化界面。这些结果表明,长排列的深地震反射初至波走时层析成像方法能够为金属矿集区深部隐伏矿床的勘探研究提供丰富的地壳浅表结构(0～1000m)信息。更多还原

【Abstract】 Four cross-deep seismic reflection profiles at the Luzhong iron-polymetallic deposits in the Lower and Middle Yangtze Reaches were performed by the Chinese Academy of Geological Sicences(CAGS) before the Chinese New Year of 2007.The near-surface(~1000m) velocity model for the Luzhong volcanoic rock basin was established for the first time using the first break-arrivals of these long-offset shot records and tomography method.The various fine imaging results show the height and undulated shape of blind syenite,discovering there is corresponding relation between positions of top interface and change of the syenite,and distribution of ore bodies,with Luohe,Xiaoling,Longqiao,and Mabianshan iron deposits all situating at the salient sections in high-speed top interface.The Luohe fault presents an obvious horizontal velocity transformation interface in line lz06-1 and line lz06-3.The research results indicate that the long-offset first arrival travel-time tomography method can provide abundant crustal shallow structure information(0~1000m) for the study of prospect for the deep concealed deposits and the potential prospecting direction for iron-polymetallic deposits in the Luzhong area,Anhui province.更多还原