南京地区金子运动与黄马青群底部石灰岩质角砾岩的成因

1935年朱森^1]等研究宁镇山脉地质时,首先提出中三叠世末期这里发生过重要的地壳运动,称金子运动,上三叠统黄马青群底部有石灰岩质角砾岩不整合在下中三叠统青龙群之上。1945年喻德渊^2]研究了安庆地区的同一地壳运动,黄马青群底部角砾岩同样不整合在青龙群之上,称淮阳运动,并强调淮阳运动结束了古生代以来下扬子地区长期海侵的历史,在地质发展中具有重要的变革作用。李四光^3]从区域的角度肯定了金子运动(淮阳运动)在华南和东南亚地区的地质意义。1962年以来,不少单位和个人^4,5,6]对此期运动作了研究,并肯定了它的存在。

THE JINZI OROGENIC MOVEMENT AND THE ORIGIN OF THE CARBONATE BRECCIA AT THE BASE OF THE HUANGMAQING GROUP IN THE NANJING AREA

Whether the Jinzi orogenic movement ever existed is a problem that in-volves the understanding of the structural evolution and mineral explorationin the Lower Yangtze region.At present,the focus of arguments is on the rea-lization of the origin of the carbonate breccia at the base of the Middle and Upper Triassic Huangmaqing Group.Proponents of the basal breccia advo-cate the existence of the movement,while that of the salt-solution brecciaor other secondary origins negate it.In this paper,the authors discuss the primary sedimentary origin of the breccia in terms of its sedimentary features,spatial distribution and occur-rence,and consider it to be a basal breccia.Besides,an analysis of the features of the carbonate breccia exposed at Mr.Yangfang,Chalukou,indicates that this kind of breccia can not beformed by the solution of gypsum and collapse of country rocks.