佛子岭群的构造属性和北淮阳带东段的推覆构造

The issue is 4th researching term in North Huai-yang Belt(NHYB), Qinling-Dabie Orogen, supported by NNSC since 1986. The main target of issue is through investigation the ages, protolith, sedimentary setting and deformation pattern of Foziling Group and the tectonics of eastern NHYB to ascertain the late Paleozoic to early Mesozoic plate tectonic architecture and evolution history before the Sino-Korea Craton finally collided with Yangtze Craton. The reseach group confirm that Foziling Group is Sinian passive continental marginal depsits in Sino-Korea craton, and the Sujiahe melange belt represents the location of Paleozoic oceanic basin and the main suture between two continents. The NHYB experienced at least two episodes of orogenic deformation since Paleozoic: late Devonian northeast direct thrusting derived from south, and the late Mesozoic NNE directed thin-skinn imbricate thrusting. The most important progress is that we identified the Caledonian orogen in Dabie section by trace the distribution of the Paleo-arc system and foreland basin, which strike NW direction and oblique with current orogenic belt. It implying the configuration of Dabie Block must great changed before and after it deep subducted into mantle depth.

大别造山根带的大面积暴露说明其上覆原有记录已遭破坏，北淮阳带成为恢复其演化历史的最佳场所。本课题通过对商固泥盆、石炭系南延部分和佛子岭群等变质层系中残留沉积地层的研究，查明大别山北侧该时段的构造面貌；通过对区域叠瓦冲断带的追索，识别前晚中生代的变形；通过变形岩体源区的地球化学研究探索北淮阳带的亲缘关系和可能的构造归属。