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91.
Individual and collective efforts to mitigate climate change in the form of carbon offsetting and emissions trading schemes have recently become the focus of much media attention. In this paper we explore a subset of the UK national press coverage centered on such schemes. The articles, selected from general as well as specialized business and finance newspapers, make use of gold rush, Wild West, and cowboy imagery which is rooted in deeply entrenched myths and metaphors and allows readers to make sense of very complex environmental, political, ethical, and financial issues associated with carbon mitigation. They make what appears complicated and unfamiliar, namely carbon trading and offsetting, seem less complex and more familiar. A critical discussion of this type of imagery is necessary in order to uncover and question tacit assumptions and connotations which are built into it and which might otherwise go unnoticed and unchallenged in environmental communication.  相似文献   
92.
The USSR has long been regarded as a resource-rich country with no need for external sources of non-fuel mineral resources. Increasingly, however, it is beginning to appear that such an assessment of the Soviet non-fuel mineral resource picture is overly optimistic. The Soviet mineral industry is beset by a variety of problems which complicate the extraction and utilization of needed minerals. The USSR remains a resource-rich country, but the difficulties it encounters exploiting its resources are multiplying. This article examines the Soviet aluminium, chromium, cobalt, copper, gold, iron, lead, manganese, platinum, titanium and zinc industries, and offers views of the Soviet resource future in each area.  相似文献   
93.
Western mine production of gold has been declining in the past five years — at the same time as the price of gold has risen dramatically. Predictions of a continued high demand for gold and the current US interest in adopting some form of ‘gold standard’ have focused attention on the supply of new gold. This paper discusses the structure of gold supply and demand, the present pattern of production of new gold and the possible effect of future price changes on Western gold mine production in the 1980s.  相似文献   
94.
The USA is becoming increasingly dependent on key strategic metals (such as chrome, cobalt, manganese and platinum-group metals) from politically unstable regions of the world. This dependence is the result of an inconsistent and fragmented US non-fuel minerals policy. Neglect of the US minerals industry has led to a decline in US mineral production and processing capabilities. Options for a comprehensive US non-fuel minerals policy include increased domestic production; increased substitution and recycling; a domestic stockpiling programme; and diversification of, and ensured access to, foreign sources of supply. These four options are examined and recommendations are made for increased mineral surveys of public lands, a regulatory review, domestic production of strategic minerals, tax incentives, conservation, stockpiling, and a foreign policy that will ensure security of supply.  相似文献   
95.
Available estimates of potentially recoverable world mineral and fuel resources are examined with a view to determining whether everyone likely to be living on earth next century could be raised to the material living standards people in developed countries now have. It is concluded that this goal is impossible. A number of fundamentally important implications follow, especially regarding the inappropriateness of growth strategies in general, goals for Third World development, and the need for ‘de-development’ of developed countries to much more frugal, self-sufficient and cooperative social systems.  相似文献   
96.
本文揭示铜陵石炭系层状金属硫化物矿床中沉积围岩、侵入岩、蚀变岩及矿石矿物的稀土元素特征。不同产状,不同成分和来源的成矿热液,在不同成矿阶段中,各矿物组合中矿石矿物的稀土元素性状各异。  相似文献   
97.
本文对多拉纳萨依金矿次生晕中金含量空间变化性进行自相关分析,并用对自相关系数进行最小二乘法拟合。通过计算方差与假设样长的关系,考核了一阶马尔科夫模型。利用最佳双边指数滤波器,输入信号(记录)进行滤被面得出各测线上金的信号输出模塑。  相似文献   
98.
隐爆角砾岩筒型矿床成矿流体演化趋势曲线特征   总被引:3,自引:0,他引:3  
阐述了隐爆角砾岩筒型矿床及其成矿过程中的隐爆流体演化趋势曲线的一般特征,在此基础上,讨论了凹山铁矿床、祁雨沟金矿床、七宝山铜金矿床等典型矿床的矿体产出特征与隐爆流体演化趋势曲线之间存在的耦合关系,结合隐爆角砾岩筒型矿床成矿流体演化的一般特征和特殊情况,对轻微剥蚀岩筒、中等剥蚀岩筒和深度剥蚀岩筒的成矿性进行了分析。  相似文献   
99.
沉积改造型金矿床系指矿源层由正常(非火山的)沉积作用形成,经后期改造未变质或弱变质的层控型金矿床,金呈微细浸染状。该类型矿床的分布明显受古地理控制,盆地边缘相、台地前缘斜坡相、台地边缘生物礁相、局限台地相以及槽盆相,特别是两相区的过渡带是矿源层形成的有利场所。其形成的大地构造环境为不同时代的被动大陆边缘区、弧后边缘海的陆侧以及初生洋盆。矿床存在的大地构造单元以加里东期、海西—印支期冒地槽褶皱带为主。  相似文献   
100.
论扬子型铜矿床及其成因   总被引:2,自引:0,他引:2  
扬子型铜矿系由三部分组成:①块状含铜黄铁矿层,②含铜的矽卡岩及磁铁矿以及接触交代带附近的交代成因铜铁矿脉,③侵入体及有关角砾岩筒中的细脉浸染矿化,后者在某些矿床如城门山被作为斑岩型铜矿。这三种类型铜矿床常被称为“三位一体”矿床,虽然第三种不一定每一场合均存在。  相似文献   
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