胶西北地区“焦家式”典型金矿床深部与浅部矿体特征对比研究

Contrast Study on Orebody Characteristics between Deep and Shallow Part of "Jiaojia Type" Typical Gold Deposits in Norhwestern Shandong Province

以近几年来胶西北地区几个大型以上规模"焦家式"典型金矿床的深部勘查资料为基础,从矿体形态、规模及产状变化、蚀变及矿化,主要有益组分金、银含量及变化、金矿物特征等方面对矿床深部和浅部矿体特征进行了综合分析对比研究。研究结果显示,矿床深部矿体规模变大,产状变缓,大部分矿体无明显的侧伏,矿体形态由复杂到简单;矿体主要有益组分金、银含量在矿体浅部的中上部相对较高,向下逐渐变贫;深部矿体总体品位较浅部低,较均匀,变化较小;在主矿体之下远离主裂面分布在黄铁绢英岩化花岗岩带内的矿体,金品位明显高于主矿体,品位变化较大;由浅而深金银品位比值有逐渐增大趋势。

On the basis of ore exploration information orebody characteristics in deep and shallow part are in deep part of “jiaojia type” gold deposit with large scale, contrasted and studied from the body shape, scale, attitude change, alteration, mineralization, the main beneficial components of gold , silver content and changes and gold ore characteristics. As showed by the results, deposits scales will become large in deep part and occurrence will be- come slow down. The majority ore bodies do not have obvious side - volt, and ore bodies will change from simple to complex forms. Major beneficial components, such as gold and silver contents are rather high in upper and middle part of shallow ore bodies and reduced gradually ; while ore bodies in deep part have low grade and changed a little. Average gold grade of ore bodies which distributed in pyrite sericitized granite belt away from the main ore bodies below the surface are higher than its in main ore bodies and changed greatly. The ratio between gold and silver grade will increase gradually from shallow to deep part.