帮布勒矿床是近年来在西藏冈底斯一念青唐古拉多金属成矿带西段新发现的大型矽卡岩型Pb-Zn矿床.闪锌矿作为该矿床的主要矿石矿物之一,其矿相学特征及化学组分对于揭示成矿物理化学条件和流体演化过程具有重要意义.本文选取帮布勒矿床近端及远端矽卡岩中不同世代闪锌矿开展详细的显微结构观察和电子探针成分研究.结果表明,帮布勒矿床闪锌矿可划分为2个世代:第Ⅰ世代闪锌矿主要产于近端矽卡岩,呈暗红色-棕红色,常与乳滴状黄铜矿共生,并交代他形磁铁矿、磁黄铁矿,Fe元素含量较高(部分闪锌矿Fe含量＞10％),Zn/Fe值＜10;第Ⅱ世代闪锌矿可进一步分为两类:第一类(Ⅱ a)闪锌矿在近端及远端矽卡岩中均有发育,呈棕黄色,充填于辉石、石榴子石等矽卡岩矿物间及其裂隙中;第二类(Ⅱb)闪锌矿主要产于远端矽卡岩中,呈黄色-浅黄色,与方铅矿和石英共生,第Ⅱ世代闪锌矿相比于第Ⅱ世代闪锌矿Fe、Mn含量明显偏低,Zn含量较高.闪锌矿Fe元素温度计估算结果显示,从第Ⅱ世代至第Ⅱ世代成矿温度逐渐降低,分别为160～314℃、138～157 ℃,与闪锌矿Zn/Fe比值指示结果一致.综上证据,本文认为帮布勒矿床早期成矿流体温度高且富含Fe、Mn、Cu等元素,随着成矿流体温度逐渐降低,流体中Fe、Mn元素含量显著降低.同时,成矿流体自矿区北西向南东运移过程中温度逐渐降低,指示在矿床南东方向具有寻找远端Manto型高品位矿体的潜力.
多不杂铜(金)矿床是西藏多龙矿集区重要的斑岩型铜矿床之一.详细的岩心编录和岩相学研究显示,多不杂铜(金)矿床发育4类磁铁矿:磁铁矿-1(Mt1)反射色呈灰白色,它形粒状,部分颗粒包含在黑云母内部;磁铁矿-2(Mt2)反射色呈粉棕色,半自形-它形粒状,边缘被赤铁矿交代,颗粒内部见少量黄铜矿;磁铁矿-3(Mt3)反射色呈粉棕色,自形-半自形,粒度小,表面平整,主要产于角岩化蚀变内;磁铁矿-4(Mt4)反射色呈深灰色,颗粒间隙被黄铁矿、黄铜矿交代.Mt1、Mt2属岩浆磁铁矿或岩浆-热液磁铁矿的过渡类型;Mt3、Mt4属岩浆-热液磁铁矿的过渡类型.Mt1、Mt2、Mt4磁铁矿形成温度大致在300～500 ℃,Mt3形成温度明显低于其他三类磁铁矿,大致在200～500℃.4类磁铁矿具有明显的地球化学差异,其中Mt1具高Ti、V,低Mn、低氧逸度的特征;Mt2具有低V,高Mn、高氧逸度的特征;Mt3具有低Ti,低Mn、Al,且Mn、Al含量与Ti呈正相关的特征;Mt4具低V、高Mn、Si、Al,高氧逸度的特征.其中Mt1形成时间最早,而Mt3形成时间最晚.高Mn和低V的磁铁矿是多不杂矿床铜矿化的指示标志.
The global supply-demand pattern for antimony-containing materials is changing as China’s mine production declines and global demand for antimony-containing materials increases in new energy sectors. An analysis of the global antimony raw materials trade pattern can help countries build their own resilient supply chains of antimony raw materials. Using material flow and complex network analysis methods, this study quantitatively depicts the global trade pattern of four types of antimony raw materials（antimony ore, antimony metal, primary processed materials of antimony, and secondary antimony） from 2002 to 2020. Additionally, the evolutionary characteristics of the global antimony raw materials trade pattern and national status are analyzed.Primary processed materials containing antimony were found to be the most important type of commodity, with trade volumes accounting for more than half of the global trade volumes of antimony raw materials. China and the United States were found to be the two countries with the most comprehensive trade status, while India, the EU,and South Korea were the countries（regions） with the fastest rise in comprehensive trade status. The EU’s import sources of antimony showed an obvious diversification trend, which significantly reduced its import dependence on China, indicating that the EU’s import strategy of critical raw materials has achieved remarkable results in recent years. China’s absolute dominance in the global supply of antimony raw materials is declining with the development of a more diversified pattern of global antimony raw materials trade.
In this paper, a research framework was formulated to analyze the complete life cycle of aluminum by using material flow analysis（MFA）, which applied the ‘top to bottom’ approach to track the flow, stock, and secondary supply of aluminum in China from 1949 to 2021. The results revealed the following: 1) The inflow of aluminum from bauxite in China was 586 Mt（million tons） from 1949 to 2021, with the domestic production and import accounting for approximately half of this number, while the actual consumption was 374 Mt. The loss of aluminum during the life cycle was severe, and the volume of resources lost reached 239 Mt. 2) In 2021, the per capita aluminum social stock was 208.9 kg, which is consistent with that of North America and Japan in the same period of economic development. 3) From 1990 to 2021, the cumulative supply of secondary aluminum in China reached 77 Mt, of which 76.7% was produced in China. As aluminum-containing products reach their life and the future demand for these products continues to rise, the era in which aluminum-containing products being scrapped will gradually usher in. Therefore, it is suggested that the loss of aluminum be reduced at every stage from the perspective of its complete life cycle. Creating a rational layout of the recycled aluminum industry,improving the utilization of secondary aluminum, optimizing the aluminum supply structure, and promoting the low-carbon transformation of the aluminum industry will help achieve the ambitious ‘carbon neutral’ and ‘carbon peak’ targets.
With the rapid development of the new energy industry, the global lithium carbonate trade volume has gradually increased, but lithium exports are concentrated in a few countries, which means that certain risks exist in the global lithium carbonate supply. To deeply understand the evolution of the global lithium carbonate trade pattern and the transmission path of its supply crisis, we constructed a global lithium carbonate trade network and cascading failure model from 2000 to 2021, outlined the trade flow of major exporters and the evolution of their trade patterns, and simulated the avalanche scale, propagation path, and impact of different supply crisis sources.We found that:（1） The global lithium carbonate trade concentration has gradually increased over the past 20 years,the top three exporting countries have remained stable, the top importing countries have substantially changed,and the trade pattern has shifted from South America supplying the world to South America supplying East Asia.（2） The impact of the lithium carbonate trade supply crisis has gradually expanded, which has gradually become dominated by indirect transmission.（3） The impact of the supply crisis in Chile has gradually expanded to China,Japan, and South Korea, but it has had the strongest impact on Europe. Avalanche frequency in Argentina and China is increasing, as are their transmission times, while the opposite has been occurring in the United States of America. We combined the evolution of the trade pattern with the spread of the crisis and clarified the degree of influence and transmission path of the main global lithium carbonate trading countries: Chile, Argentina, China,Germany, etc., as the sources of the supply crisis. The above results can be applied to help maintain the stability of global lithium carbonate trade and help major trading countries to adopt corresponding measures to alleviate the supply crisis.
