大兴安岭弧盆系构造地球化学特征及地质意义

Tectono-geochemical characteristics and geological insignificance in arc basin system of Da Hinggan Mountains

根据区域化探成果,对大兴安岭弧盆系的4个Ⅲ级构造单元及主要构造的地球化学特征进行了研究。归纳总结了各构造单元的地球化学元素的分布特征,划分了4个异常带。研究表明:地层、岩性及构造对元素的分布控制较为明显。通过对4个Ⅲ级构造单元含矿性的对比,发现呼玛弧后盆地成矿元素以Au、Zn及铁族元素为主;多宝山岛弧成矿元素以Au、Cu、Mo及铁族元素为主;嫩江—黑河构造混杂岩成矿元素以Au为主;剌尔滨河岩浆弧成矿元素以Au、Ag、W、Mo为主。

Based on the results of regional geochemical exploration,the 4Ⅲ grade structural units in arc-basin systerm of Da Hinggan Mountains and their geochemical characteristics are studied.The distribution characteristics of geochemical elements of each tectonic unit are summarized,and 4 anomalous zones are divided.The study shows that the distribution of elements is obviously controlled by strata,lithology and structure.Through the comparison of the ore bearing properties of 4 Ⅲ grade tectonic units,it is found that the oreforming elements of the Huma back-arc basin are mainly Au,Zn and iron group elements,and the main metallogenic elements of the Duobaoshan arc are Au,Cu,Mo and iron group elements.The metallogenic elements of the Nenjiang-Heihe tectonic melange are mainly Au,and the ore forming elements of the Riparian river magma arc are mainly Au,Ag,W and Mo.