【摘要】 本文根据重大地质问题野外地质调研、锆石SHRIMP年代学与岩石地球化学研究,揭示出秦岭造山带腹地明显存在晋宁期和加里东期的两期叠加板块汇聚结合带。新提出晋宁期具主次两条板块汇聚结合带,系中新元古宙古中华陆块群裂解—古秦岭多岛洋形成(1800~940 Ma),可识别出具蛇绿岩、岛弧火山岩与深成侵入岩、陆缘弧变质地层四位一体的组合,时空紧密关联。北部即古华北南缘古商丹带,沿北秦岭南缘被后者商丹带重叠,南部为古扬子西北缘板块汇聚结合带,总体延伸近北东向,从三湾(西乡)、黑木林、峡口驿、三岔子、鞍子山、马道、佛坪至小磨岭以东。其南段受扬子地块燕山期向北推挤位错,三湾蛇绿构造混杂岩带呈构造窗出露,中段遭晚期东西向勉略带构造捋顺。而早古生代Rodinia超大陆裂解——原特提斯洋形成(561~447),认为消失的原特提斯洋是中国最具规模的早古生代大洋,商丹—昆南板块汇聚带,便是中国大陆造山带最重要的一条大地构造界线。研究了两期板块汇聚结合带分布与区域成矿关系,对铁、铜、镍钴等区域成矿前景赋予新的启示。更多还原

【Abstract】 Based on field investigation and research of SHRIMP dating and lithogeochemical survey,superimposed conjunction zones of plates formed in two phases of Jinningian period and Caledonian period are evidently present in the hinterland of Qinling orogenic zone.There are two junction zones of plates formed in the Jinningian period by splitting of the middle-Neoproterozoic old Chinese landmass group-archipelagic ocean during ancient Qinling period(1800～940Ma),in which a quaternity composed by ophiolite,island-arc volcanic rock,plutonic intrusions and epicontinental metamorphic rocks is distinctive to be closed relationship in space-time.The ancient Shang-Dan zone in the southern margin of the Old North China Plate was superimposed by the Shang-Dan zone along the south margin of the northern Qinling Mountains in the north convergent plate zone of the northwest margin of the Yangtze plate is in the south,generally extending in near northeast direction,from Sanwan(Xixiang),Heimulin,Xiakouyi,Sanchazi,Anzishan,Madao,Foping to the east of Xiaomoling.In the south portion,northwardly squeezing dislocation by Yangtze landmass occurred in Yanshanian period,outcropping fenster formed by Sanwan ophiolitic tectonic melange and the middle portion was twisted to order by EW Mianlue tectonic zone in the late period.Splitting of the Paleozoic Rodinian supercontinent formed the Prototethys,which is considered to be the largest Early Paleozoic ocean in China and the convergent zone of the Shangdan and the Kunnan plates to be the most important tectonic boundary.Study of the distribution and the relations to regional metallogenesis of the plate convergent zones formed in two phases would provide some new considerations to the regional metallogenesis of iron,chalcopyrite,nickel and cobalt in this area.更多还原