| 内蒙古哈达庙含金隐爆角砾岩带地质特征及成因探讨 |
| 点此下载全文 |
| 引用本文：聂凤军,张洪涛,孙浩,樊建廷.1991.内蒙古哈达庙含金隐爆角砾岩带地质特征及成因探讨[J].地球学报,12(1):81-90. |
| DOI： |
| 摘要点击次数: 4989 |
| 全文下载次数: 5466 |
|
|
| 中文摘要:内蒙古哈达庙含金隐爆角砾岩带位于天山-内蒙海西晚期褶皱带镶黄旗复向斜内,由一系列角砾岩墙(脉)及其伴生的电气石和石英、电气石裂隙脉组成。金矿化与角砾岩墙(脉)的规模和热液蚀变强度呈正比,金矿石品位可达数十克/t。野外地质观察和地球化学研究结果表明:角砾岩带的形成过程不是一个独立的岩浆活动事件,而是形成石英闪长岩-花岗闪长岩的岩浆在超浅成部位通过裂隙式隐爆方式形成的,岩浆体系的剧烈爆破,可使含金流体在压力释放地段迁移和沉淀,从而生成具有工业价值的金矿床。 |
| |
| GEOLOGICAL CHARACTERISTICS AND ORIGIN OF THE HADAMIO GOLD-BEARING CRYPTOEXPLOSION BRECCIA ZONE,NEI MONGGOL |
|
|
| Abstract:Situated in the Xianghuangqi syclinorium of Tianshan-Nei Monggol fold belt formed during the late Hercynian orogenesis, the Hadmio gold-bearing cryptoexplosion breccia zone is mainly controlled by a NE or WE-trending structure line. It consists of 33 breccia dikes (or vein) and tourmaline fissure vein groups. The breccia dikes and fissure veins, some of which contain native gold, are commonly from tens to several hundreds meters long, the longest one being 650 m. They are usually from 1 to 4 m wide and may be up to 6 m in width. The rock fragmets of the dikes are mostly granodiorite and granodiorite porphyry. The matrix in the breccia may be divided into three types, i. e. altered mineral assemblage, mineral and rock fragments and metal sulfids, of which the sulfides are closely associated with gold mineralization.The result of isotope study shows that breccia dikes are characterized by: δ34S, 2.8‰ δD, -46‰; δ18OH2O 2.4‰ and 87Sr/86Sr, 0.7088. The REE pattern of the whole breccia rock exhbits a rightward decline curve with the δEu value of 0.34. The REE content, LREE/HREE and δEu of the cementation are lower than those of the rock fragment in the breccia dike, which has similar REE pattern to that of granodiorite in the area.On the basis of the above mentioned facts, it may be considered that the granitic rocks and breccia were originated from the anatexis of crustal rocks. They are resulted from the different evolutional stages of comagmatic sources. When cryptoexplosion and boiling of granitic melt took place, the P, T, pH and fO2 conditions were changed and gold were deposited as native gold, electrum and gold-bearing pyrite in the breccia dikes. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
|
|
|
|
|
