云南省者太地区金锑矿找矿预测-来自水系沉积物测量的证据

Prospecting of Gold-Antimony Deposit in the Zhetai Area of Yunnan Province:Evidence from Stream Sediment Survey

云南者太地区位于开远-丘北金成矿带东缘,该区及其周边已发现卡林型金矿和木利式锑矿床(点)20余处,具有良好的金、锑矿找矿前景。本文以1 ∶ 5万水系沉积物测量19种元素含量数据为基础,统计分析了水系沉积物地球化学参数、元素相关性、成矿有利度系数等指标,总结了元素组合、富集贫化规律及其与地质背景、地质构造与成矿作用的关系。区内主要富集元素为Au、Sb、As、Bi、Cd,主要高分异元素为Au、Sb、As、Cd,且具有较高的成矿有利度系数。结果显示,Au元素异常严格受近东西向构造带、北西向构造带、北东向构造带,以及二叠系-三叠系不纯碳酸盐岩、硅质岩、细碎屑岩等因素控制;而Sb元素异常与近东西向构造带、台盆相沉积环境、泥盆系硅化灰岩(硅化碎屑岩等)有着密切联系。依据水系沉积物异常特征和成矿地质条件,圈定综合异常7处,划分出3个找矿远景区,指出了区内今后的找矿方向。

The Zhetai area in Yunnan Province is located at the eastern edge of the Kaiyuan-Qiubei gold metallogenic belt. A series of Carlin-type gold deposits and Muli-type antimony deposits(occurrences)distribute in and around the Zhetai area. Based on stream sediment geochemical data at a scale of 1 ∶ 50000 ,this work studied the characteristics of geochemical parameters,relativity analysis of elements,metallogenic advantage coefficient,and summarized the relationship among elements assemblage,element enrichment and dilution regularity with geological background,tectonics,mineralization. The major enrichment elements are Au,Sb,As,Bi and Cd. The elements with high ore-forming favorable coefficient and high-differentiation are Au,Sb,As and Cd. The results show that the Au element is strictly controlled by the EW-trending tectonic belt,the NW-trending tectonic belt,the NE-trending tectonic belt,the Permian-Triassic impure carbonate rock,siliceous rock,fine clastic rock and other factors. The Sb element anomaly is closely related to EW-trending tectonic belt,the basin-sedimentary environment,and the Devonian silicified limestone(silicided clastic rock,etc.). Seven anomalous zones and three metallogenetic prospective areas in the Zhetai area were delineated based on the geologic information and elemental anomalies.This work can provide useful information for the future exploration.