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对侵位于彭庐地块东南边缘与程浪断裂带毗邻的前寒武纪花岗岩和出露于程浪深断裂带内的超基性岩墙群的微量元素地球化学特征进行了研究,结果表明前者属板内与岛弧环境的过渡类型,后者代表典型的火山岛弧环境。结合前人在区域构造和地质年代学的研究成果,认为晋宁运动时期,扬子板块东南缘散布着多个小型块体,在华夏板块向扬子板块方向的俯冲过程中,障公山地块先与彭庐地块沿程浪断裂带发生拼合,同时形成程浪超基性岩墙群;与此同时,彭庐地块内则表现为大规模的岩浆侵入作用。在各小型块体陆续发生碰撞后,扬子板块与华夏板块在晋宁运动晚期最终碰撞拼合,火山岛弧环境转换为造山带构造,因此,彭庐地块、障公山地块等火山岛弧均成为华南造山带的组成部分。
The trace element geochemical characteristics of the Precambrian granite intruded to the southeastern edge of Penglu block and the Chenglang fault zone and the ultrabasic dyke swarms exposed in the Chenglang deep fault zone are studied. The results show that the former Plate and island arc environment transition type, the latter represents a typical volcanic island arc environment. Based on the research results of regional tectonics and geochronology, it is considered that during the Jinning Movement, there are many small blocks scattered in the southeast margin of the Yangtze Plate. During the subduction of the Huaxia Plate towards the Yangtze Plate, And the Penglu block along the Chenglang fault zone to form a Chenglang ultrabasic dyke group; meanwhile, the Penglu block shows large-scale magmatic intrusion. After the successive collisions of small blocks, the Yangtze plate and the Huaxia plate eventually collided with each other in the late Jinning movement, and the volcanic arc environment was converted to orogenic belt structure. Therefore, volcanic island arcs such as the Penglu block and the Caogongshan block Have become part of the South China Orogenic Belt.