| 初论地幔热柱与成矿——以冀西北金银多金属成矿区为例 |
| 点此下载全文 |
| 引用本文：.1996.A preliminary discussion on mantle plume and metallogenesis of Au-Ag-multimetal mineralization are in northwest Hebei[J].Mineral Deposits,15(3):249~256 |
| Hits: 3331 |
| Download times: 2010 |
|
| 基金项目:地质矿产部“八五”科技攻关项目 |
|
| 中文摘要:作者通过对冀两北金、银多金属矿化集中区成矿规律和物探航磁、重力及遥感信息的综合研究，提出冀西北地区存在一个超越内蒙地轴与燕山褶皱带两个不同历史大地构造单元之上的中生代地幔热柱构造。文中例举了地幔热梓构造标志特征，探讨了地幔热柱构造地质作用（超变质作用、岩浆作用、成矿作用）及其时空演化规律，建立了地幔热柱构造的壳幔成矿模式。 |
| 中文关键词:地幔热柱 中生代超变质作用 成矿模式 冀西北金银多金属成矿区 |
| |
| A preliminary discussion on mantle plume and metallogenesis of Au-Ag-multimetal mineralization are in northwest Hebei |
|
|
| Abstract:Comprehensive studies have revealed that there is an obvious and enormous thermal dome structure-mantle plume in the gold-silver-polymetallic mineralized area of northwest Hebei. The mantle plume is about 200 km in diameter, with the center located in Xuanhua and various strata and structures around the center distributed in the form of concentric rings. This special tectonic unit oversteps two different tectonic units-Inner Mongolian axis and Yanshanian platform fold belt. From its center to periphery, fractures vary from ductile shear zone to brittle-ductile shear nappe structure zone and to ductile-brittle fracture zone. In the circular area, there exists a suite of Mesozoic mantle source rock association including alkali basalts and ultraalkaline-alkaline rocks. Besides, Mesozoic continental rift type volcanic rocks are extensively distributed over the area. Mantle source magmatic activity mainly took place at the center, whereas crust-mantle mixed source magmatic activity occurred along the periphery. The known large and superlarge gold deposits concentratedly exist in the center, forming Chongli-Chicheng auriferous shear zone. Silver polymetallic ore deposits are present at peripheral semicircular ductile-brittle shear nappe structures. Therefore, the authors have formulated a regular spatial distribution pattern of gold-silver-polymetallic deposits characterized by "gold inner and silver outer", namely the gold-silver-polymetallogenic series which were the ultimate evolution products of the hotspot in Mesozoic. In the whole evolutional process, massively upwelling of mantle source substances and crust-mantle interaction acted as a large enrichment system for gold-silver-polymetals, the enormous dome structure is the transferring system for ore materials, and hypabyssal structures, magmatism and thermal fluid action make up the locating system of ore deposits. This paper has discussed ultra-metamorphism, magmatism and metallization of the Mesozoic mantle plume, and established a metallogenic model. |
| keywords:mantle plume, Mesozoic ultrametamorphism, metallogenic model, gold-silver-polymctallic mineralized area in northwest Hebei |
| View Full Text View/Add Comment Download reader |
