Genesis of the alkali-rich porphyries in Yunnan

Abstract

The alkali-rich porphyries formed in the structural relaxation epoch of the Himalayan Movement. The tectonic setting and crustal structure in which the rocks formed and the compositional regionization feature of the rocks indicate that the magma formed inside the crust, which is further proved by REE. Sr and Pb isotope data. Combined the aforesaid data with the result of REE inversion, it is suggested as a new opinion that the alkali-rich porphyries were the remelting product of the mixture of mantle rocks intrusing into the crust with crustal material.

Keywords

genesis / rare-earth element / alkali-rich porphyry / geochemical inversion / Yunnan

References

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