Rare Earth Elements are strategically critical metals of all countries in the world with the medium and heavy REEs are particularly important. A large number of granitoids of different ages are distributed in Laos. In this region, the climate is humid, hot and rainy, resulting strong weathering that is favorable for the formation of ion-adsorbed REE deposits. In order to identify the geological characteristics and distribution of Laos′ rare earth resources, and to analyze its investment and exploitation prospects, this study carried out systematic field investigations and related analyses throughout the country, as well as summarizing the progress of recent REE exploration in the region. The results show that the metallogenic characteristics of REE in Laos are comparable to those in southern China, which belongs to a typical weathered crust elution-deposited rare earth ore(WCED-REO). The orebodies are mainly concentrated in completely weathered layers of granitoid, and the cap layers are relatively thicker than those of southern China. The ore bodies are stratiform and lentoid, with thicknesses of several meters to 20 meters. The average grades of ionic phase rare earth range from 0.4‰ to 0.7‰. Most of them have REE ditributional patterns similar to those of the Xinfeng REE mine in Ganzhou and Jiangxi, which belong to the middle yttrium rich europium type. The rare earth resources of Laos are mainly distributed in the northern parts, such as the Xieng Khouang and Huaphane provinces. The total rare earth resources of the two provinces are estimated to be up to 600, 000 tons. With the opening of Laos′s rare earth policy and the gradual improvement of China′s rare earth strategy, investment in the exploitation of Laos rare earth resources and establishing an overseas strategic base for rare earth resources can support China′s demand for ion-adsorbed rare earth resources in a long-term and stable manner. Meanwhile, it can also facilitate mutual cooperation in mineral resources, significantly contributing the future of both countries.

十多年来,全球矿业热潮汹涌,特别是在2008年金融海啸发生后的几年里,不少人认为千载难逢的全球矿业投资机会已经到来,央企、民企、地勘单位和个体老板,甚至还有不少农民兄弟,纷纷冲向全球可能的矿区,在海外矿业资本市场及不少矿业项目,演绎了一个又一个轰轰烈烈挥金如土的故事.

当前,中国海外资源布局时机已经来临.做出这个判断主要基于七个原因.中国经济的持续繁荣,仍是世界矿业发展的主要动力;加快国际化进程,是中国矿业调整产业结构的迫切需要;“一带一路”战略,是驱动全球经济增长的新动力;大型国有企业的国际化进程进入快车道;大宗商品价格持续走低,大多数矿业公司处境艰难;矿业公司资产估值大幅度缩水:“十三五”期间,随着中国经济运行质量的显著提高,全球矿业形势将明显好转.2016-2018年将是中国海外资源布局的最佳时期.

Based on detailed analysis of regional metallogenic geological background and conditions, it is held that the Duolong ore district of the West Bangong Lake arc has metallogenic prospecting and resources potential for porphyry Cu-Au deposits. Through the exploration in 2013, the authors made a breakthrough in Tiegelongnan. Copper reserves of the Tiegelongnan ore district has reached a superlarge ore deposit, and this deposit has thus become the largest porphyry Cu(Au)ore deposit in the Duolong ore district as well as the major exploration breakthrough in 2013. The deposit is located in early Cretaceous Meiriqiecuo formation of the middle Duolong ore district, and has a close temporal relationship with early Cretaceous intrusive granodiorite porphyry, granite porphyry and concomitant hydrothermal mineralization breccia. The orebodies mainly occur in the lower middle Jurassic Sewa Formation feldspar quartz sandstone, lithic sandstone intercalated with dark gray to deep black silty slate and mineralized porphyry. Orebodies exhibit concealed dome and are characterized by great downward extension in the forms of network veins, veinlets, and disseminations. Hydrothermal alteration is well developed, with obvious zonation, strong silicification, sericitization, and widely superimposed advanced argillic alteration. The denudation degree of the ore district is very low. The surface only develops limonite and clay, with no copper mineralization. Alteration and mineralization increased gradually downward, and the mineralization extension reaches one thousand kilometers at depth without closure. The upper copper mineralization is of chalcocite-digenite-enargite association, exhibiting characteristics of the Cu-S system, which gradually changes into bornite and chalcopyrite characteristics of the Cu-Fe-S system. Copper mineralization is associated with Au, Ag mineralization and assumes positive correlation. Compared with other porphyry Cu-Au ore deposits in the Duolong ore district, this deposits is poor in gold. The exploration breakthrough of the deposit provides a good example for the exploration work of the mining company and also has significance for regional ore-prospecting.

Based on the integrated analysis,the authors summarize that the capital financing of the geological exploration companies and enterprises has gone through three stages from the single channel to the multiple financial options.The multiple financial options,such as fiscal financing,financing through mineral exploration cooperation,equity financing,debt financing,stock financing and international financing,etc.,have become the major selection for the Chinese geological exploration companies and enterprises.

<正>本文主要对世界公众勘探公司及其项目动态作一跟踪研究,可知,世界约80%的公众勘探公司是在加拿大及澳大利亚的证券交易所上市的公司;世界80%的公众勘探公司为中小型公司;世界85%的勘探矿种为贵金属、铜、铀、钻石和煤矿;世界73%的公众勘探公司及76%的勘探项目集中分布于北美、澳大利亚和拉丁美洲三个地区;世界40%的勘探经费用于77%的勘探项目。世界公众勘探公司较为及时准确地披露相关信息,以及Infomine Inc.和SNL Metals Econom ics Group等咨

<正>由加拿大金属经济集团(MEG)推出的《2012年世界勘探趋势》显示,从2011年一季度到2012年第四季度,初级矿业公司的勘探费用会增加74亿美元。根据MEG的研究,在这一时期内,在大多数地区的大部分公司支撑强劲的勘探开支的目标都是金矿。MEG认为,勘探趋势与其他行业一样,是随经济形势变化的。比如2011年是一个很好的时期,各类公司拥有充足的现金,他们显示了对风险投资较大

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应用岩石薄片鉴定、X射线粉晶衍射、X射线荧光光谱和ICP-MS等分析方法,研究了热带季风型气候条件下老挝Attapeu省Antoun地区二叠纪花岗闪长岩上发育的砖红土型风化壳矿物组成、常量元素和稀土元素地球化学特征.结果表明,风化产物呈酸性,风化壳表土上形成薄层硅质壳层,表土中石英含量最高、铁氧化物含量低和高岭石含量低,符合典型的灰化土特征.随着风化作用加强,Fe2O3、TiO2和Al2O3出现富集,K2O、Na2O、CaO和MgO出现淋失.石英出现富集原因可能是雨季降水冲刷和酸性水淋溶掉高岭石等黏土矿物,而旱季SiO2含量上升至地表富集形成硅质薄壳缘故.剖面稀土元素分布型式为轻稀土富集型,∑REE在风化壳中部达到最高值318 mg kg-1,剖面上Ce和Eu均呈正异常-负异常-正异常变化趋势,∑REE最高值出现在Ce和Eu负异常和(Fe2+/Fe3+)较高层位,∑REE与Fe2O3显著正相关.REE富集与铁铝氧化物和黏土矿物吸附有关,也与相对还原的酸性环境有关.

Located in northeast Champasak Province,Lao PDR and having erupted in later Mesozoic-Cenozoic,the basalt of Boloven Plateau has formed a well-developed lateritic regolith(weathering crust) under long-term tropical monsoon climate and tropical monsoon forest.In a site on Boloven Plateau 11 samples of a regolith profile were collected,and then pulverized to 200 meshes in laboratory.All the 11 samples were analyzed for major elements and REE concentrations by mean of XRF and ICP-MS respectively.The analytical results of major elements showed that Na2O and MgO were leached the most,followed by K2O and CaO with slowly leaching velocity while to some leaching amount in the whole profile.TiO2,P2O5 in LR157 and LR158 were 6.07%,1.45% and 8.43%,0.82% respectively which were the highest values in all 11 samples,and the same as CaO in LR157 and LR158.∑REE in weathering basalt(LR140,LR141) were 57.8×10-6 and 87.9×10-6,obviously lower than most other samples.In addition,while weathering and pedogenesis increasing,∑REE were consequently gradually enriched up to 775×10-6 and 1003×10-6 under the top soil(LR158,LR157).LREE/HREE ratios of all samples,ranging from 3.59 to 14.94,showed a typical pattern of enrichment in LREE in chondrite normalization plots.When weathering was developed,Ce gradually rose to strongly positive anomaly from a slightly negative anomaly,and on the contrary Eu gradually decreased to more strongly negative anomaly from a slightly positive anomaly.The extents of variation of Ce and Eu anomalies were relatively significant in whole profile.There was obvious correlativity between REE and minerals hosting P2O5 or TiO2.And ∑REE reached to the highest values in LR157 and LR158 where P2O5 and TiO2 had the highest values also.The enrichment of ∑REE and positive anomaly of Ce were present under acid-oxidizing environment(pH ranging from 5.23 to 6.12 and Fe2+/Fe3+ 0.007～0.13).It suggested ∑REE could be enriched under acid-oxidizing environment.

表生作用主要与气候、植被、基岩、地貌、时间等因素有关,具有与内生作用不同的特征,如低温、低压、水、二氧化碳、生物有机体等参与.目前发现的表生成矿的矿床类型有风化矿床和部分沉积矿床.表生作用形成多种矿床,包括(1)红土型的金、镍、铁、锰、钴、铝土、稀土元素、铀矿、砂锡、砂金、铌钽砂矿、金红石等残积坡积和淋积矿床;(2)高岭土矿、蒙脱土矿等残余富集矿床;(3)镍、铀矿等淋积矿床.此外还有一些沉积矿床.在热带亚热带地区,红土型铝土矿、红土型金矿和红土型镍矿等风化矿床分布广泛(南京大学地质系,1979;顾皓民译,1994;廖士范,1997;王瑞廷等,2002;高振敏等,2002;肖振民,2002;陈骏等,2004;方维萱等;2005).

The climate of Laos is typically tropical monsoon type.Boloven Basalt Plateau is located in Champasak Province of south Laos.The Plateau is covered by basalt dated Cenozoic age in large area and has been uplifted slowly.The annual average rainfall and temperature in Boloven Basalt Plateau is 3742.5mm and 20.1℃ respectively,so there has been formed laterite regolith.The regolith with limonite and bauxite is averagely more than 25m deep in the whole Plateau.The geochemical characteristics of twenty trace elements in regolith are discussed.