SUMMARY
Types of lead-zinc mineralization in
Huổi Pao and Co Gi San areas and their relationship to magmatic rocks in
the T� Lệ Depression
Nguyễn
Văn Niệm, Mai Trọng T�, Nguyễn Văn Học,
Đỗ
Đức Nguy�n, Đo�n Thị Ngọc Huyền
Lead-zinc ore in Huổi Pao and Co Gi San areas are characterized by special features, which can be divided into two types of mineralization: the first type is polymetal-silver-sulphide bearing gold occurring in Huổi Pao, while the second is polymetal-sulphide-nickel-cobalt-copper-silver occurring in Co Gi San.
The above-mentioned two types of mineralization are closely related to magmatic felsic rocks. Regarding space, lead-zinc ore is always distributed in rhyolite, rhyotrachyte, trachyte of the T� Lệ and Ng�i Thia Complexes and is closely related to granite, granosyenite massifs of the Phu Sa Ph�n Complex. About their origin, there are 2 hypotheses as follows: the first hypothesis states that ore solution and magmatic solution body are co-original, but ore solution was separated in the second stage; the second � ore solution was derived from granitic, granosyenitic formations of the Phu Sa Ph�n Complex and gabbro formation of the Nặm Chiến Complex at the first stage (Jurassic) as well as at the final stage (19 Ma) with their source originated from effusives (T� Lệ Complex) and subvolcanic rocks (Ng�i Thia Complex).
Based on geochemical characteristics of ore-forming minerals of the types of mineralization, this paper determines that the denudation level of lead-zinc ore body in Huổi Pao is weak and indicator elements for ore prospecting are Pb-Zn-Sb-Ag-Cd (W).
Người bi�n tập: TS. Đỗ Quốc B�nh