怒江、澜沧江、金沙江地区构造与成矿作用

据野外调查资料,将怒江、澜沧江、金沙江地区划为三个大的构造单元,即扬子板块西缘、印度板块北东缘和处于上两者之间的交接带或转换构造带。本文以大地构造格架为背景,结合成矿建造与构造变动的内在联系,在本区划出11个主要金属成矿带。追溯构造演化与成矿作用关系划出6大成矿阶段,即前特提斯阶段、古特提斯阶段、古特提斯碰撞阶段、碰撞后继阶段、中特提斯阶段及陆内强挤压阶段。其中以第四、第六两个成矿阶段最重要。本文还着重描述了构造运动形式及构造变形与成矿作用的关系,解剖了川西呷村含金富银多金属矿、藏东玉龙斑岩铜矿、滇西金顶铅锌矿、哀牢山带金矿等大型典型矿产形成的构造地质背景。

Tectonism And Metallogenesis Of The Nujiang-Lancangjiang-Jinshajiang Region(Sanjiang Region)

Based on the data obtained in field survey, we have divided the Sanjiang region into three large tectonic elements, i.e. , the western margin of Yangtze plate, the northeastern margin of Indian plate and the connective or transitional belt between them. Especially in the last belt, several ophiolite zones are developed as remains of the paleo-Tethys oceanic crust; late Variscan trench-arc systeIn, Indosinian trench-arc-basin system and their corresponding deposition zones can be observed clearly. Another important feature lies in the existence of quite a few stratigraphic and metamorphic blocks of different ages among those zones, which have been turned into elongated and lozenge-shaped bodies of different sizes as a result of late compression and shearing.Based on the newly-divided geotectonic framework and the internal relations between the metallogenic formation and the tectonic evolution, 11 major metallogenic zones are recognized in Sanjiang region. A study of the relationship between tectonic evolution and mineralization has led us to divide the ore-forming process into six major ore-forming stages, namely pre-TethyS, paleo-Tethys, collision, post-collision, Meso-Tethys, and inner-continental extrusion. This paper also emphatically describes styles of tectonic movement and tectonic deformations related to mineralization such as splitting-seafloor spreading, subduction, collision, ductile shearing, napping and strike-slip faulting.