东昆仑拉浪麦地区地球化学勘查异常下限确定方法对比研究

A COMPARATIVE STUDY ON METHODS FOR DELINEATING ANOMALOUS THRESHOLDS OF ELEMENTS IN GEOCHEMICAL PROSPECTING OF LALANGMAI TUNGSTEN POLYMETALLIC MINE IN EAST KUNLUN AREA

东昆仑地区是我国重要成矿带,地球化学勘查作为该区基础性的勘查手段在区域找矿、矿区及其外围找矿发挥了重要作用。地球化学勘查工作中,异常下限的确定是圈定地球化学异常的基础和关键。拉浪麦钨多金属矿区地球化学勘查工作中利用传统统计法、EDA法、含量—面积分形法分别对土壤地球化学分析元素计算确定异常下限,并结合成矿地质条件对三种方法计算出的异常下限进行综合对比研究,发现EDA法得出钨等元素异常不漏掉隐伏矿床形成的矿致异常,从而达到快速精准高效的找矿效果,具有很好代表性。因此,在东昆仑地区寻找钨多金属矿地球化学勘查中,采用EDA法确定异常下限是可行的。

The East Kunlun is an important metallogenic belt in China.As a basic prospecting method,geochemical prospecting has played a major role in prospecting for minerals in regional prospecting,and prospecting in mining areas and their adjacent areas.As the confirmation of anomalous threshold is the basis of,and key to delineate geochemical anomalies in geochemical prospecting,traditional statistical method,EDA,and content-area fractal method are used to analyze the contents of the elements to determine the anomalous thresholds respectively in the geochemical prospecting of Lalangmai tungsten polymetallic mining area.Meanwhile,in combination with geological conditions for mineralization,comprehensive comparisons have been made for anomalous thresholds which are derived from the above-mentioned methods.It has been found that the tungsten and other elements anomalies calculated by EDA method can demonstrate the mineralization-related anomalies formed by the concealed deposits.With these efforts,a rapid,accurate and efficient prospecting method with good representativeness can be achieved.Therefore,it is feasible to use EDA to determine the anomalous thresholds in the geochemical prospecting of tungsten polymetallic deposits in the East Kunlun.