土壤地球化学测量在文登青庄地区金矿勘查中的应用

Application of Soil Geochemical Survey in Exploration of Gold Deposit in Qingzhuang Area of Shandong Province

摘要:

为有效、准确的寻找金矿床，结合文登青庄地区基岩出露情况，选择开展了1∶1万土壤地球化学测量。该次工作测网选择100m×40m，局部加密至100m×20m，采集20～30cm深处的BC层土壤，过40目样筛，过筛后样品重量均大于150g，分析Au，Ag，Cu，Pb，Zn，As，Bi，Mo等8种元素。通过对各元素分析结果进行R型聚类分析，认为将As，Sb元素作为寻找Au矿的主要指示元素在该区不适用，该区Au与Bi的相关性较好。通过合理确定各元素的背景值和异常下限，圈定单元素异常190处，根据元素组合特征圈定综合异常19处，其中AP7，AP19成矿条件较好，划分为乙1类异常，重点开展异常查证工作。通过探槽施工、化验分析等异常查证工作，在两个异常内均发现金矿（化）体，样品中金品位（0.30～3.64）×106，确定了土壤地球化学测量在该区找矿工作中的适用性和有效性。区内发现的金（矿）化体赋存于蚀变破碎带内，矿化蚀变主要有黄铁矿化、硅化、绿泥石化，与邻近的西院下金矿相似，初步确定区内寻找的金矿床类型应为构造角砾岩碎裂岩型金矿床。

Abstract:

In order to find gold mineralization, combining with outcropped condition of basic rocks in studying area, soil geochemical survey with the scale of 1∶10000 has been carried out. Observation network is 100m×40m and local refinement is 100m×20m. After collectting BC layer soil in 20~30cm deep and passing 40 mesh sieve, the weight of samples is more than 150, and 8 elements as Au, Ag, Cu, Pb, Zn, As, Bi, Mo have been analyzed. Through type R cluster analysis, it is known that it is not suitable to regard As and Sb elements as the main indicator elements for searching Au ores in this area. The correlation of Au and Bi in this area is good. Though calculating and choosing reasonnable background value and the threshold of each element, 190 element anomalies have been circled. According to element combination, 19 comprehensive anomalies have been circled. Among them, AP7, AP19 have good metallogenic conditions and are divided into 1 class. Abnormal verification work should be carried out in this area firstly. Through abnormal verification work ,such as exploratory trench and laboratory analysis，gold (mineralization) have been found in two abnorma areas. Au grade is 0.30 x 106~3.64x106. It is proved that soil geochemical survey is suitable and effective in ore prospecting. Gold (mineralization) body occured in altered fracture zone in this area. Mineralization mainly include pyritization, silicification and chloritization. It is similar to Xiyuanxia gold deposit. The type of gold deposit is determined as alteration structural brecciascataclastic rock type gold deposit.