Geochemical Characteristics of Monzonite Granite from the Daping Gold Mining Area, Yunnan Province and Geologic Significance

详细信息   

• 责任者：Wang Zhihua(Gold Geological Institute of CAPF ; Langfang ; Hebei 065000 ; China) ; Guo Xiaodong
• 刊名：Geology and Prospecting
• 出版年：2012
• 卷期：48(3)
• 关键词：金矿 ; gold ores ; 二长花岗岩 ; monzogranite ; 云南 ; Yunnan Province
• 页码：p.618-628
• 图表：illus., 40 tables, 6 refs.
• 分类号：0801,1001
• issnNo：ISSN0495-5331
• isbnNo：CN11-2043/P

摘要

The Daping gold mining area has underwent active magmatic activities. Granites of large scales outcrop widespread as medium- to coarse - grained monzonite granite in lithology. Contents of SiO2range from 67.32% to 71.71% and A1203is between 14.54% and 16.66%, belonging to peraluminous granitoid rocks. The rock is rich in large ion lithiphile elements of Sr, U, Rb, Ba and light rare earth elements （LREE） , and is depleted in the high field strength elements （ Ta, Nb and Ti）. It shows a ＂TNT＂ negative anomaly ; ~Eu ranging from O. 80 to 1.44. 87 Sr/86 Sr varies in the range of 0. 7078 ~ 0. 7436, averaging 0. 7256, higher than the contemporary value of primitive mantle 0. 7045. The ratio 143 Nd/t44 Nd is in the range of 0.5119 0.5122, averaging 0. 5120, lower than the contemporary value of primitive mantle 0.512638. end is in the range of -2.5 - -4.2, averaging -3.98. All above indicate that the monzonite granite derived from a crust-mantle mixing belt through partial melt and formed in the tectonic regime of syn- or late col- lisional stage. The source of monzonite granite is identical to the ore-forming fluid, and the rock bodies provided heat and main mineralizing fluid in the Daping gold deposit.