黑河地区北宽河组地层含矿性地球化学评价——以黑河大新屯金锑矿区为例

Geochemical evaluation for ore potentiality of the Beikuanhe formation in Heihe area:a case study of the Daxintun gold deposit in Heihe

通过对黑龙江省黑河大新屯金锑矿区新元古代北宽河组二云母片岩、砂质板岩、大理岩岩石样品化学元素光谱分析,发现该地层三类岩石Au、As、Sb、Hg含量是上部陆壳丰度数十倍至上千倍,富集系数普遍偏高,在地层中呈偏峰和多峰分布,几何平均与算术平均比值小于0.65,变异系数（Cv）、叠加强度系数（D）大于1.5,相关系数十分接近,为0.87~0.97。综合参数表明该地层遭受后期地质作用强烈改造,存在后期矿化叠加的可能性。Au、As、Sb、Hg参数近协调一致,表明这些元素在区域矿化上有共生的性质。Au、As、Sb、Hg参数特征表明北宽河组可为金、锑等成矿提供丰富的成矿物质来源,故认为北宽河组为金、锑等矿的矿源层。

Spectroscopic analysis about the two-mica schist, sandy slate and marble of the Beikuanhe formation shows that the element content of Au, As, Sb, Hg is ten to thousands times more than average abundances of ele- ments in the upper crust of global continent, and the enrichment coefficient is generally higher. Au, As, Sb, Hg in the strata is in deflection peak or multi-peaks, geometric mean and arithmetic average ratio are both less than 0.65, the coefficient of variation （Cv）, intensity of the superposition coefficients （D） are more than 1.5, the corre- lation coefficient ranged from 0.87 to 0.97. These data show that the strata were altered by a series of geological processes and then addition of epigenetic mineralization. The date of Au, As, Sb, Hg is similar with the symbiosis characteristics. Beikuanhe formation is source bed of the Au and other mineralization elements.