Core-mantle-type extensional mode and dynamic mechanism of the magmatic metallogenic explosion of the Yanshanian in the Cathaysian metallogenic province

The Cathaysian metallogenic province in the southeastern China is the most important multi-metal and non-metal metallogenic province with W, Sn and precious metals along the marginal-Pacific metallogenic megaprovince. The geological investigation results and the isotopic dating data show that the magmatic metallogenic explosion caused by the intracontinental active orogeny in this region came from intracontinental crustal vulnerable zones, originally occurred in the middle section of the Qinzhou-Hangzhou juncture during the middle Jurassic period (172±Ma), intensified in the Nanling region during the Late Jurassic period, and extensively extented to outside, lastly ended in the late early Cretaceous (99±Ma), thus forming the core-mantle extended mode centred with the middle section of the Qinzhou-Hangzhou and Nanling region and the outer side as the mantle. Meanwhile, it restricted the regional magmatism, ore-forming features as well as the magmatic metallogenic regularity from early to late, core to mantle, deep to shallow and shallow to surface. The creep effection of the upper crust caused by the large-scale adjustment of the lithosphere materials and the magmatic mineralization is significant, due to the movement taking place under the sitting of the higher degree of the crustal hardenability. Therefore, the unique dynamic mechanism of the magmatic metallogenic core-mamtle-type was formed as a result of the intensive left-lateral sinistral shearing and the recombination of the weak subduction.