柬埔寨全国地球化学填图与成矿远景区预测

Nationwide geochemical mapping and division of metallogenic belts in Cambodia

中文关键词:地球化学填图  成矿元素异常  成矿远景区预测  国家尺度  柬埔寨

keywords:geochemical mapping  anomalies of ore-forming elements  metallogenic belts prediction  nationwide  Cambodia

中文摘要:基于“一带一路”国际合作框架，文章首次完成了覆盖柬埔寨全境（18.1×10⁴ km²）的1∶100万低密度河漫滩水系沉积物地球化学填图，系统分析了1795件样品中的71种元素与氧化物，构建了柬埔寨国家尺度地球化学基准与首套地球化学图集，填补了区域地球化学数据空白。研究发现，区内成矿元素呈现显著的富集与分异特征，Au、As、Sb、Hg、Mo、Mn、Ti、Fe₂O₃等主要成矿元素具高富集系数（K>1）和高变异系数（CV>1），属于典型的“富集-集中型元素”。地球化学组合异常与区域地质体和已知矿床展现出清晰的耦合关系：Cu-Ni-Co-Cr-Mn组合异常严格受基性-超基性岩和中酸性岩体控制，与接触带型铜铁矿化空间高度一致；Au-As-Sb-Hg组合异常清晰指示了构造破碎带内中低温热液金矿化的发育；W-Sn-Bi-Mo组合异常则与酸性侵入岩密切相关，反映了高温热液钨锡矿化事件。基于区域成矿规律在特提斯成矿域-印支成矿省框架内，将柬埔寨划分为5个三级成矿带，并综合地质与地球化学信息圈定了6处成矿远景区。研究填补了柬埔寨国家尺度地球化学空白，为区域成矿规律研究、矿产资源潜力评价及绿色矿业发展提供了科学依据。

Abstract:Under the framework of the “Belt and Road” international cooperation initiative, this study has accomplished the first nationwide 1∶1 000 000 scale low-density floodplain sediment geochemical mapping covering the entire territory of Cambodia（181 000 km²）. A total of 1795 samples were systematically analyzed for 71 elements and oxides, establishing a national-scale geochemical baseline and producing the first geochemical atlas for Cambodia, thereby filling critical gaps in regional geochemical data.The research reveals significant enrichment and differentiation characteristics of ore-forming elements in the region. Key metallogenic elements such as Au,As, Sb, Hg, Mo, Mn, Ti, and Fe₂ O₃ exhibit high enrichment coefficients（K>1） and high variation coefficients（CV>1）, identifying them as typical “enriched-concentrated elements”. Geochemical composite anomalies demonstrate clear correlations with regional geological units and known mineral deposits: Cu-Ni-Co-Cr-Mn composite anomalies are strictly controlled by mafic-ultramafic rocks and intermediate-acid intrusions, showing strong spatial consistency with contact zone-type copper-iron mineralization; Au-As-Sb-Hg composite anomalies clearly indicate the development of intermediate-low temperature hydrothermal gold mineralization along structural fracture zones; while W-Sn-Bi-Mo composite anomalies are closely related to acidic intrusive rocks, reflecting high-temperature hydrothermal tungsten-tin mineralization events.Based on regional metallogenic regularity in the Tethyan metallogenic domain-Indochina metallogenic province framework, Cambodia was divided into five third-order metallogenic belts. Integrating geological and geochemical information, six prospective metallogenic areas were delineated. This study fills the gap in national-scale geochemical data in Cambodia and provides a scientific basis for research on regional metallogenic regularity, assessment of mineral resource potential, and the development of green mining.