四川得荣地区徐麦超基性岩体地球化学特征及成矿潜力

Geochemical Characteristics of Xumai Ultrabasic Rock Bodies and Its Metallogenic Potentiality in Derong,Sichuan

对四川得荣地区徐麦超基性岩体的主量元素进行了分析.结果表明,该岩体中SiO2含量为35.27%～42.25%,MgO含量34.85%～38.16%,ALK为0.019 3%～0.031 9%,m/f比值为7.06～12.78;微量元素分析成果显示其富相容元素Cr、Co、Ni,几乎亏损所有的不相容元素;稀土元素球粒陨石标准化曲线显示轻稀土富集而重稀土亏损;δEu值介于0.82～12.61之间,具明显正铕异常特征.结合该岩体的地质特征,认为徐麦超基性岩体属于镁质超基性岩,含矿性较好,其成矿远景意义相对较大.

Major elements of of Xumei ultrabasic rock bodies in De rong, Sichuan were analysed results show that the content of SiO2 is from 35.2% to 42.25%, MgO from 34. 85% to 38. 16% The ALK from 0. 019 3% to 0. 031 9%, m/f from 2. 1 to 4. 0. The microelement analysis data show that the contents of the compatible elements of Cr, Co and Ni are very high, almost defict of all of incompatible elements. Chondrite standard curve of rare earth elements reveals an enrichment of light rare earth and deficit of heavy one. δ Eu is from 0. 82 to 12.61, and Eu is positive anomalies. Based on the study of the geological characteristics of the rock bodies, it is proposed that the uhramafic rock bodies belong to magnesium uhrabasic type. The ore deposit with good orepotentiality has been found in the ultrabasic rock bodies. So the authors suggested that there is great prospection this rock bodies.