New explanation of the genesis of the metamorphic rocks in the Hongge region,Panzhihua,southwestern Sichuan

Unlike the adjacent Huili Group metamorphic rocks,the metamorphic rocks in the Hongge region,Panzhihua,southwestern Sichuan are not attributed to the pre-Sinian regional metamorphic rocks,as indicated by the 1∶50 000 geological survey.On the contrary,they bear a striking resemblance to the lithologic associations,lithochemistry and REE distribution patterns for the Upper Sinian Baguanhe sandstones,Guanyinya Formation and Dengying Formation.For these reasons,they should be interpreted as the thermal contact metamorphic rocks originated from the Sinian sedimentary rocks which were influenced by the Variscan-Indosinian magmatism.