当前全球矿业形势分析与展望

全球矿业发展与工业化进程密切相关,具有与全球经济发展周期基本一致的显著的周期性特征。在同一个周期内,各种资源需求在时间上具有波次(递进)性,它决定着矿业的持续与繁荣。从2003开始全球矿业进入了第3个周期,其特征包括矿业产业集中度加剧、垄断特征更加显著、矿产品低成本时代终结等。同时,这一时期出现了大量国际金融资本进入矿产品市场的现象,使得矿产品价格体系趋于复杂化。从中长期来看,中国、印度、非洲等新兴经济体工业化、城镇化进程不会停滞,刚性资源需求将推动此轮超级周期继续前行。从中短期来看,欧美债务危机继续升级恶化,中东格局正发生着重大变化,全球经济二次探底风险愈发增大。在全球经济增长不如预期、矿产品需求下降、新增矿山产能释放和矿产品价格进入新一轮调整阶段的情况下,未来一段时期内,全球矿业形势将表现为"需求放缓、价格高位、震荡加剧"。     

Evaluation of surface sediment contamination by polycyclic aromatic hydrocarbons in the "Saco do Laranjal" - (Patos Lagoon, Brazil)

This paper evaluates the concentration of Polyaromatic hydrocarbons - PAHs in the Estuarine area of the Patos Lagoon, more precisely in a local named "Saco do Laranjal" in Pelotas City (southern Brazil). The samples were collected in May 2008. The concentrations of 16 US-EPA priority polycyclic aromatic hydrocarbons (PAHs) were determined by gas chromatography with a mass spectrometry detector (GC/MS). The sum of PAHs concentration ranged from 7.3 to 92.8μgkg(-1) in dry weight. The positive correlation (Pearson test) between the total organic material (TOM) and the total PAH concentration (0.98) suggests that TOM plays an important role in controlling the PAHs levels in the sediments. According to the observed ratios of individual PAHs, the contamination in the studied area is originated, predominantly pyrolytic sources. The values found are considered under normal levels and indicates a not impacted area.     

“协优”成矿预测方法的理论探索与实践

根据西藏野外地质工作难度大、工作程度极低、找矿信息少且获取极其困难这一实际, 在认真学习、吸收前辈成矿预测理论精髓及大量找矿实践和理论思考的基础上, 基于系统性、关联性、目标一致性、不充足判据的充足化、复杂与精确的反比性原则, 提出了西部工作程度极低地区快速逼近找矿目标的“协优”成矿预测法, 即只要优选出少量相互关联、目标一致、最能揭示某种类型成矿本质特征的关键信息组合, 就可能导致该类型矿床被发现.强调直接信息的先导作用及少数相互关联信息的明确指示意义, 突出信息与预测目标的一致性, 这样可有效减少信息的不确定性和多解性, 从而降低找矿风险.试图从另一个视角、另一种思路来认识和探讨西部工作程度极低地区的成矿预测问题.该方法应用于冈底斯、北喜马拉雅及念青唐古拉等成矿带的勘查实践, 找矿取得了巨大突破.这对促进冈底斯相邻地区乃至整个西部地区的找矿评价、技术方法进步等具有重要的参考与借鉴意义.      

金融危机对矿业的影响及分析预测

席卷全球的金融危机正在疯狂肆虐,矿业也难以独善其身.金融危机导致矿产品价格全线跳水、矿业公司股价大幅下跌、矿产品需求下降.矿产品价格大幅下跌是矿产品价格在挤出泡沫之后的一种理性回归.矿业发展自身的规律与百年不遇的金融危机的相互叠加、相互影响,加速了此轮矿业繁荣周期的终结并开始了走向下行期的步伐.金融危机给矿业带来了挑战与机遇,但机遇远大于挑战.对此提出如下建议:改善中国矿业投资环境,调整矿产品进出口政策;培育大型跨国矿业公司,提高竞争力;建立国外资源储备基地,吸引海外地质勘查人才;重新审视和再认识地勘基金的定位;抓住有利时机整合资源,促进矿业结构调整.     

公益性地学数据的功效：拉动商业性矿产勘查

通过分析商业性矿产勘查业对公益性地学数据的需求、公益性地学数据对商业性矿产勘查的短期和长期影响,探讨了公益性地学数据和商业性矿产勘查的关系,肯定了公益性地学数据在促进矿产勘查中的积极作用,提出了利用公益性地学数据拉动商业性矿产勘查、服务于商业性矿产勘查的基本思路.     

非传统化探方法研究的新进展

在20世纪的找矿实践中,水系沉积物、土壤和岩石地球化学测量等传统化探方法发挥了令矿产资源勘查界瞩目的重要作用.随着深部找矿,特别是覆盖区找矿工作的日益增多,传统化探方法已不完全适应这种找矿条件,急需有新的方法技术予以补充.20世纪诞生的一套非传统化探方法,如选择性提取法、生物地球化学测量、地下水地球化学测量、地下气体测量等,重又受到青睐.在现代化学分析技术的支撑下,选择性提取技术成为当前化探界研究的热点,试点性研究显示了其找寻隐伏矿的有效性;生物地球化学找矿方法在植物积累元素的控制条件、分析测试方面均取得了较大进展,已经从幼年期进入成熟的早期阶段;地下水地球化学测量方法在地下水中矿物饱和度与物质计算、高质量的物理化学数据的获取和不同矿床类型的元素化舍物指示标志的研究与评价方面做了大量的工作.同时,数据处理技术、重矿物地球化学找矿标志和同位素地球化学示踪技术的研究近年来也受到了极大关注.实验性研究表明,尽管这些非传统技术在找寻隐伏矿方面显示了良好的应用前景,但仍有许多问题需要深入研究.     

Temporal and spatial variations in nutrient stoichiometry and regulation of phytoplankton biomass in Hong Kong waters: influence of the Pearl River outflow and sewage inputs

In 2001, the Hong Kong government implemented the Harbor Area Treatment Scheme (HATS) under which 70% of the sewage that had been formerly discharged into Victoria Harbor is now collected and sent to Stonecutters Island Sewage Works where it receives chemically enhanced primary treatment (CEPT), and is then discharged into waters west of the Harbor. The relocation of the sewage discharge will possibly change the nutrient dynamics and phytoplankton biomass in this area. Therefore, there is a need to examine the factors that regulate phytoplankton growth in Hong Kong waters in order to understand future impacts. Based on a historic nutrient data set (1986-2001), a comparison of ambient nutrient ratios with the Redfield ratio (N:P:Si=16:1:16) showed clear spatial variations in the factors that regulate phytoplankton biomass along a west (estuary) to east (coastal/oceanic) transect through Hong Kong waters. Algal biomass was constrained by a combination of low light conditions, a rapid change in salinity, and strong turbulent mixing in western waters throughout the year. Potential stoichiometric Si limitation (up to 94% of the cases in winter) occurred in Victoria Harbor due to the contribution of sewage effluent with high N and P enrichment all year, except for summer when the frequency of stoichiometric Si limitation (48%) was the same as P, owing to the influence of the high Si in the Pearl River discharge. In the eastern waters, potential N limitation and N and P co-limitation occurred in autumn and winter respectively, because of the dominance of coastal/oceanic water with low nutrients and low N:P ratios. In contrast, potential Si limitation occurred in spring and a switch to potential N, P and Si limitation occurred in eastern waters in summer. In southern waters, there was a shift from P limitation (80%) in summer due to the influence of the N-rich Pearl River discharge, to N limitation (68%) in autumn, and to N and P co-limitation in winter due to the dominance of N-poor oceanic water from the oligotrophic South China Sea. Our results show clear temporal and spatial variations in the nutrient stoichiometry which indicates potential regulation of phytoplankton biomass in HK waters due to the combination of the seasonal exchange of the Pearl River discharge and oceanic water, sewage effluent inputs, and strong hydrodynamic mixing from SW monsoon winds in summer and the NE monsoon winds in winter.     

Seasonal and spatial dynamics of nutrients and phytoplankton biomass in Victoria Harbour and its vicinity before and after sewage abatement

This study investigated the seasonal and spatial dynamics of nutrients and phytoplankton biomass at 12 stations in Hong Kong (HK) waters during a three year period from 2004 to 2006 after upgraded sewage treatment and compared these results to observations before sewage treatment. Pearl River estuary (PRE) discharge significantly increased NO(3) and SiO(4) concentrations, particularly in western and southern waters when rainfall and river discharge was maximal in summer. Continuous year round discharge of sewage effluent resulted in high NH(4) and PO(4) in Victoria Harbour (VH) and its vicinity. In winter, spring and fall, the water column at all stations was moderately mixed by winds and tidal currents, and phytoplankton biomass was relatively low compared to summer. In summer, the mean surface phytoplankton chl biomass was generally > 9 microL(-1) in most areas as a result of thermohaline stratification, and high nutrients, light, and water temperature. In summer, the potential limiting nutrient is PO(4) in the most productive southern waters and it seldom decreased to limiting levels ( approximately 0.1 microM), suggesting that phytoplankton growth may be only episodically limiting. The mean bottom dissolved oxygen (DO) remained > 3.5 mg L(-1) at most stations, indicating that the eutrophication impact in HK waters was not as severe as expected for such a eutrophic area. After the implementation of chemically enhanced primary sewage treatment in 2001, water quality in VH improved as indicated by a significant decrease in NH(4) and PO(4) and an increase in bottom DO. In contrast, there were an increase in chl a and NO(3), and a significant decrease in bottom DO in southern waters in summer, suggesting that hypoxic events are most likely to occur in this region if phytoplankton biomass and oxygen consumption keep increasing and exceed the buffering capacity of HK waters maintained by monsoon winds, tidal mixing and zooplankton grazing. Therefore, future studies on the long-term changes in nutrient loading from PRE and HK sewage discharge will be crucial for developing future strategies of sewage management in HK waters.     

成矿理论与勘查技术方法现状与发展趋势

近20年来,许多地球科学的新概念、新理论、新方法和高新技术应用于矿产资源评价与勘查中,大大地提高了成矿理论和找矿预测的研究水平。成矿学的研究在经历了矿床模式、板块构