青海省纳日宗地区水系沉积物地球化学特征及找矿远景

纳日宗地区位于南祁连岩浆弧和宗务隆山—夏河—甘加裂谷的接触部位，该区及其周边已发现金属矿床(点)10余处，具有良好的金、铅、铜矿找矿前景。以该区1∶5万水系沉积物测量的16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Sn、Pb、Bi、As、Sb，成矿有利度系数高的元素有As、Pb、W、Au、Bi、Sb。结果显示，水系沉积物元素异常沿NW—NWW向断裂构造分布，初步认为构造发育地段具有较好的Au、Pb、W找矿潜力。依据单元素异常特征和成矿地质条件，圈定综合异常74处，划分出3个找矿远景区，指出了各找矿远景区的找矿方向。

Geochemical Characteristics of Stream Sediments and Prospecting in the Narizong Area,Qinghai Province

The Narizong area in Qinghai Province is located at the boundary between the southern Qilian Mountain magmatic arc and Zongwulong Mountain Xiahe Ganjia rift valley. A series of small sized metallic mineral deposits (occurrences) distribute in and around the Narizong area. Based on the stream sediment geochemical data at scale 1∶50 000，the authors 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 Sn,Pb,Bi,As and Sb. The elements with high ore forming favorable coefficient are As,Pb,W,Au,Bi and Sb. The results show obvious elemental anomalies along NW and NWW trending faults. It suggests that there is the explorational potential for gold, lead and wolfram in the structural zone. Seventy four anomalous zones and three metallogenetic prospective areas in the Narizong area were delineated, based on the geologic information and elemental anomalies．This work expected to provide useful information for the future exploration.