浙闽粤滨海地区成矿演化和矿床时空分布的控制因素

浙闽粤滨海地区中生代的成矿作用主要与岩浆作用有关，矿床在空间上有明显的分带性，在时间上具有明显的迁移性，但这种成矿分带和迁移完全不同于东太平洋安第斯和美国西部平行于俯冲带或垂直海岸线的成矿分带和迁移模式，区域中生代矿床的时空分布和成矿演化明显受着区域的构造应力作用方式，岩浆作用特征，赋矿地层和岩石的含矿性特征以及成岩成矿后的风化剥蚀程度等因素的影响。

FACTORS CONTROLLING THE METALLOGENIC EVOLUTION AND TIME-SPACE DISTRIBUTION OF THE ORE DEPOSITS IN ZHEJIANG-FUJIAN-GUANGDONG COASTAL AREAS

In Zhejiang-Fujiang-Guangdong coastal areas, Mesozoic mineralization is mainly related to Mesozoic magmatism. The metallogenic belt has distinct spatial zonation and obvious temporal migration, which, however, are different from characteristics of Andes and western America in the east coast of the Pacific Ocean. The zonation and migration of the former areas intersect the coastline whereas those of the latter areas are parallel to the coastline. The time-space distribution and mineralization evolution of regional Mesozoic ore deposits are controlled evidently by the regional Mesozoic tectonic setting and stress field, the magmatism characteristics, the ore potentiality of regional sedimentary- metamorphic strata and the denudation after the Mesozoic magmatism and mineralization. The regional magmatis m and metallization took place after the collision and collage of micro-landmasses in southeast China continent and under the geological setting of transformation from the Tethyan tectonic region to the paleo-Pacific tectonic region. There are three periods of tectonic movement, magmatism and mineralization, namely the Tehyan tectonic region large-scale intracontinental compression-S type and S-I type volcanic-intrusive complexes-W and Sn mineralization in the early period, the paleo-Pacific tectonic region strikeslip type volcanic-intrusive complexes-Pb-Zn-Ag polymetallic mineralization in the middle period, and the continental spreading and splitting-bimodal volcanic rocks and A type granites-Cu- Au mineralization in the late period. The regional metallogenic characteristics are reflections of ore potentiality of the regional basement rocks of the Mesozoic volcanic rocks. Since the formation of the complexes and ore deposits , this district has been long in the uplifting and continental denudation state. From south to north, the ages of the volcanio-intrusive complexes become smaller and smaller, the denudation time is getting shorter, and the denudation depth turns smaller. As a result, there exists distinct zonation in metallic elements and genetic types. The magmatic-mesothermal W-Sn polymetallic deposits occur mainly in eastern Guangdong ( the southern metallogenic belt), the subvolcanic-hydrothermal porphyry Cu-Mo deposits are distributed in eastern Fujian ( the middle belt) andthe volcanio-epithermal Ag-Pb-Zn deposits are scattered in eastern Zhejiang ( the northern belt). The metallogenic evolution is associated with the tectonio-magmatic evolution, and the metallogenic epoch becomes younger and younger from south to north.