Metallogenetic characteristics of gabbro-diorite rock mass of the Lanniping district of Dongchuan copper deposits,Yunnan

Gabbro-diorite rock mass are exposed recently in 219# 、179# 、139# and 59# new section of the Lanniping district of the Dongchuan copper deposits in Yunnan,which have obvious zonate phenomena.The geochemical characteristics show that it belongs to basic rock in alkaline basaltic series,and similar to east area of Emeishan basalt and synchronization diabase.They have no obvious hybridism of continental crust when magmatic crystallization differentiation.The Fe-Cu-Au ore bodies were found on the edge of gabbro-diorite rock mass.The ore bodies have more iron-mineral which is close to gabbro-diorite rock mass.The bornite and tetrahedrite increase where is away from the rock mass.In respect of ore forming element,diorite-gabbro rock mass have high concentrations of Cu(0.204 %),Fe(12.72%),Au(0.099g/t),TiO2(3.691%),which implies that the rock mass may be metallogenic rock,and have direct relationship with formation of copper-iron deposits in Yingming group.