大兴安岭多宝山铜成矿区植物地球化学特征及找矿意义

Characteristics and Prospecting Significance of the Phytogechemistry in Duobaoshan Cupper Metallogenic Field,Daxing'anling Area,NE China

在森林覆盖区利用植物地球化学找矿具有一定优势。对黑龙江省呼玛县多宝山铜矿区和相邻的呼玛县罕达—气白石砬子—宽河对照区进行植物地球化学找矿研究。植物样品采集以植物样方测量中常见植物为主,分别采集植物的根、茎、叶,并配套采集岩石和土壤各层位的样品,植物样品使用ICP-MS方法测试。植物中成矿元素对比和总富集系数(TEC)显示,在铜成矿区可以形成比较明显的植物地球化学异常。通过矿化岩石-土壤-植物元素相关分析和屏障系数(SC)证明,植物中元素异常与成矿作用具有成因联系。植物地球化学找矿干扰因素比较多,可利用元素在植物根、茎、叶器官内的分配特征来确定采样介质。提出利用衬度系数(CC)、组合衬度系数(CCC)、屏障系数(SC)等多指标方法选择有效指示植物,综合分析后认为白桦和胡枝子可作为多宝山铜成矿区有效指示植物。在大兴安岭森林覆盖区利用植物地球化学找矿是可行的。

Effective prospection can be take using phytogeochemistry in forest cover area. The study of phytogeoehemistry in Duobaoshan copper metallogenic field and adjacent area has been carried out. The samples are common plants in the plant samples measurement and taken from roots, stems and leaves, respectively. The rock and soil samples were collected from the same place with plant samples. The analytical method of the plant samples is ICP-MS. Obvious phytogeochemical anomalies can be recognized by the metallogenic elements contrast method and total enriched coefficient （TEC）. The phytogeochemical anomalies have genetic relationship with the mineralization proved by the shielding coefficient （SC） and the correlation analysis of mineralized rock, soil and plants. There are some interfered factors in phytogeochemical exploration. The phytogeochemical samples can be determined by the distribution of elements in the plant organs. The contrast coefficient（CC）, combination contrast coefficient（CCC） and shielding coefficient（SC） have been used to select effective indicator plants. It can be concluded that platyphylla and lespedeza are the effective indicator plants in Duohaoshan copper metallogenic field. Phytogeochemical exploration in Daxing＇anling forest cover area is practicable.