陕西山阳县夏家店金矿床地质特征、控矿因素与金的富集规律

Geological characteristics, ore-controlling factors and gold enrichment regularity of the Xiajiadian gold deposit,Shanyang County, Shaanxi Province

在南秦岭造山带中带山阳-柞水-修石崖断裂带及其附近发现和勘探了一大批金矿床。最近又在东秦岭震旦系与寒武系界面新发现和勘查了夏家店金矿,该矿床也位于山阳-柞水-修石崖断裂的分支断裂系统中。山阳-柞水-修石崖断裂被认为是印支—燕山期的逆冲推覆构造,其分支断裂——镇安断裂为逆冲剪切推覆构造。含金矿源层寒武系水沟口组被逆冲推覆于震旦系灯影组白云岩之下,形成岩石组成为围岩的构造角砾岩,局部地段保留有强揉皱蚀变的炭泥硅质板岩,这种板岩本身为金的富矿体。主要矿石类型为角砾岩型。本文从矿床地质特征出发初步总结了该矿床的控矿因素和金的富集规律,为下一步该类型金矿床的找矿提供依据。

A large number of gold deposits have been found near the Shanyang-Zhashui-Xiushiya fault and its vicinity in the South Qinling orogenic belt. Recently the Xiajiadian gold deposit has been found and explored in the contact between the Sinian and Cambrian in the East Qinling. This deposit is also located in a subsidiary fault system of the Shanyang-Zhashui-Xiushiya fault. The Shanyang-Zhashui-Xiushiya fault is thought to be an Indosinian-Yanshanian thrust nappe structure and its branch fault, the Zhen′an fault, is a shear thrust nappe structure. The Cambrian Shuigoukou Formation, which is the gold-bearing source bed, is thrust beneath dolostone of the Sinian Dengying Formation, forming tectonic breccia as country rocks. Locally strongly wrinkled altered siliceous slate. This kind of slate itself is a gold ore shoot. The ores are mainly of breccia type. Departing from the geological characteristics, this paper preliminarily sums up the ore-controlling factors and gold enrichment characteristics of the Xiajiadian gold deposit and provides a basis for looking for this type of gold deposit in the next stage.