【作者】 张维萍； 赫英； 董振信；

【Author】 Zhang Weiping~(1,2*) He Ying~2 DONG Zhengxin~3 1.Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education,Department of Chemistry,Northwest University,Xian,Shaanxi 710069,P.R.China. 2.State Key Laboratory of Continental Dynamics,Ministry of Education;Department of Geology,Northwest University,Xi’an 710069 China;Department of Chemistry,Northwest University,Xi’an 710069,China; 3.Geological Museun of China,Beijing 100812,China

【机构】 西北大学合成与天然功能分子化学教育部重点实验室西北大学化学系； 西北大学大陆动力学国家重点实验室,西北大学地质系； 西北大学大陆动力学国家重点实验室西北大学地质系； 中国地质博物馆；

【摘要】 测定了中国北方新生代玄武岩中各类包体的主量元素及其中26件橄榄岩包体的金含量。各类包体主量元素含量反映出包体的形成有两种不同趋势,其一是二辉橄榄岩包体可能主要是上地幔及其演化产物;其二是二辉岩包体、镁铁质麻粒岩包体及长英质麻粒岩包体可能是具有壳幔过渡特征的包体。CaO≥2%的橄榄岩包体,其金含量高于2×10^-9;CaO<2%的橄榄岩包体,其金含量却均低于0.5×10^-9。橄榄岩包体中金含量与 CaO 含量的相关性表明,其中的金早期可能主要赋存于单斜辉石中,反映地幔包体中的 Au 可能与地幔演化和熔融程度有关。更多还原

【Abstract】 The 72 xenoliths in Cenozoic basalt have been collected from several regions in north china Their major data and Au data of the 26 peridotite xenoliths were determined.The major data difference of granulite,pyroxenite and peridotite xenoliths suggests characteristics of lower crust,crust-mantle transitional zone and higher mantle.The figures of variation of selected major oxides (wt.%) versus MgO for the xenoliths suggest that peridotite xenoliths are all remains by different degree partly melted processes of plump mantle.The geochemical characteristics suggest that the strong and multiple mixing processes may have occurred universally both in the lower crust and crust-mantle transitional zone.The relativity of the gold contents vs the CaO contents for the 26 peridotite xenoliths suggests that gold may be in clinoaugite and implicates that gold of xenoliths may be corresponding to process of mantle evolution and molten degree of mantle.更多还原