Pre-1.6 Ga rocks comprise around 45% of the onshore area of Western Australia (WA), constituting the West Australian Craton (WAC) (including the Archean Yilgarn and Pilbara Cratons) and the western part of the North Australian Craton (NAC). These areas provide the conditions suitable for diamond formation at depth, and numerous diamondiferous lamproite and kimberlite fields are known. As emplacement ages span close to 2500 Ma, there are significant opportunities for diamond-affinity rocks being present near-surface in much of the State, including amongst Phanerozoic rocks. WA’s size, terrain, infrastructure and climate, mean that many areas remain underexplored. However, continuous diamond exploration since the 1970s has resulted in abundant data. In order to advance future exploration, a comprehensive database of results of diamond exploration sampling (Geological Survey of Western Australia 2018) has been assessed. The Yilgarn and Pilbara Cratons have spinel indicators almost exclusively dominated by chromite (>90% of grains), whereas (Mg,Fe,Ti)-bearing Al-chromites account for more of the indicator spinels in the NAC, up to 50% of grains at the Northern Territory (NT) border. Increasing dominance of Al in chromites is interpreted as a sign of weathering or a shallower source than Al-depleted Mg-chromites. Garnet compositions across the State also correlate with geological subdivisions, with lherzolitic garnets showing more prospective compositions (Ca-depleted) in WAC samples compared to the NAC. WAC samples also show a much broader scatter into strongly diamond-prospective G10 and G10D compositions. Ilmenites from the NAC show Mg-enriched compositions (consistent with kimberlites), over and above those present in NT data. However, ilmenites from the WAC again show the most diamond-prospective trends. Numerous indicator mineral concentrations throughout the State have unknown sources. Due in part to the presence of diamondiferous lamproites, it is cautioned that some accepted indicator mineral criteria do not apply in parts of WA. For example Ca-depleted garnets, Mg-depleted ilmenites and Cr-depleted and Al-absent clinopyroxenes are all sometimes associated with strongly diamondiferous localities. Quantitative prospectivity analysis has also been carried out based on the extent and results of sampling, age of surface rocks relative to ages of diamond-prospective rocks, and the underlying mantle structure. Results show that locations within the NAC and with proximity to WA’s diamond mines score well. However, results point to parts of the WAC being more prospective, consistent with mineral chemical data. Most notable are the Hamersley Basin, Eastern Goldfields Superterrane and the Goodin Inlier of the Yilgarn Craton. Despite prolific diamond exploration, WA is considerably underexplored and the ageing Argyle mine and recent closure of operations at Ellendale warrant a re-evaluation of diamond potential. Results of mineral chemistry and prospectivity analysis make a compelling case for renewed exploration.
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1.
2008—2009年度矿业投资环境调查简况
2009年加拿大弗雷泽研究所发布了2008—2009年度矿业公司关于世界主要国家或地区矿业投资环境评价的调查结果。调查涵盖全球658家矿业公司,2008年这些公司勘探总额为34亿美元,约占全球总量（2008年全球非铁矿产勘探支出为144亿美元）的24％。 相似文献
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1 2005年度面上项目受理申请和同行评议情况
2005年度共受理面上申请项目310项,较2004年增长约19．2％。其中自由申请项目240项,较2004年增长了21．2％;青年基金申请项目65项,较2004年增长了18．2％。地区基金申请项目5项。 相似文献
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《中国勘察设计》2006,(11)
为了解2005年度施工图设计文件审查工作的开展情况,同时检验各地相关的信息化建设和应用情况,我司要求各地通过"勘察设计质量信息管理业务系统"上报了《2005年度施工图审查情况统计表》。现根据各地上报的统计数据,作如下情况汇总及简要分析(部分指标同时附2004年统计,供参考):一、审查机构情况截至2005年底,全国共有各类审查机构819家,比2004年的760家略有增加。(一)按机构类别分类(二)按机构性质分类二、审查人员情况截至2005年底,全国共有审查人员16,633人,比2004年的15,046人略有增加。(一)按机构类型分类一类审查机构有审查人员9,457人… 相似文献
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二、月度机場成本計划的編制 (一)編制月度机場成木計划的目的地質勘探計划是组織、指導地質勘探生產、施工的依据。地質勘探成本計划是年度地質勘探生產計划的重要組成部分,它規定了为完成年度生產任务所必須支出的生產費用和完成各項工程單位工作量的平均 相似文献
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近年来,龙游县国土资源局以溪口国土资源管理所（以下简称溪口所）建设为示范,在全县基层国土所深入实施“亮起来”工程,取得了显著成效。特别是溪口国土所先后被评为全国“三无”活动先进单位、“2004-2005年度省级文明国土资源所”、“2006—2007年度省级文明国土资源所”、“2007、2008年度衢州市群众满意基层站所”、“2008、2009年度局先进集体”等荣誉称号, 相似文献
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1955—2008年冬克玛底河流域冰川径流模拟研究 总被引：11，自引：7，他引：4
采用HBV水文模型,对长江源区有冰川覆盖的冬克玛底河流域日径流进行了模拟试验研究.使用冬克玛底河流域周边4个有长期观测资料的气象站日气温、日降水数据,结合流域内自动气象站实测数据,应用多元回归法插值恢复了流域1955—2004年日气温数据,应用降水梯度与反距离权重相结合的方法恢复了流域1955—2004年日降水数据.采用数据质量较好的2004/2005年度和2006/2007年度两个物质平衡年水文气象数据进行模型参数的率定,应用2005/2006年度和2007/2008年度水文气象数据进行模型参数的检验.在确定模型能较好的模拟流域年月径流深的前提下,采用率定好的模型参数和恢复的气象资料,恢复了1955—2004年冬克玛底河流域的年径流深;依据水量平衡原理,得到流域冰川物质平衡变化.结果表明:1955—2008年冰川物质平衡呈亏损趋势,平均-136.0mm.a-1;年径流深呈波动增加趋势,平均增加5.61mm.a-1.径流深的增加量中约34%是因为降水增加所致,66%是因为温度升高导致冰川消融加剧所致. 相似文献
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磨溪气田位于四川盆地川中古隆中斜平缓构造带南部,其嘉二气藏为一中型海相气藏,含气面积为179.45km2,主力产层为三叠系嘉陵江组嘉二2亚段。气藏勘探始于1979年,于2004年勘探取得突破,至2005年底探明地质储量为326.59×108m3,年产天然气4×108m3。气藏储层为局限海—蒸发海台地碳酸盐岩微相,储层的发育分布主要受沉积作用和成岩作用控制,气藏类型为岩性—构造复合圈闭,气藏气水关系复杂。论述了气藏的发现和勘探开发历程及气藏的基本地质特征,总结了取得勘探突破的实践、认识与启示。 相似文献
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Fuzzy logic mineral prospectivity modelling was performed to identify camp-scale areas in western Victoria with an elevated potential for hydrothermal-remobilised nickel mineralisation. This prospectivity analysis was based on a conceptual mineral system model defined for a group of hydrothermal nickel deposits geologically similar to the Avebury deposit in Tasmania. The critical components of the conceptual model were translated into regional spatial predictor maps combined using a fuzzy inference system. Applying additional criteria of land use restrictions and depth of post-mineralisation cover, downgrading the exploration potential of the areas within national parks or with thick barren cover, allowed the identification of just a few potentially viable exploration targets, in the south of the Grampians-Stavely and Glenelg zones. Uncertainties of geological interpretations and parameters of the conceptual mineral system model were explicitly defined and propagated to the final prospectivity model by applying Monte Carlo simulations to the fuzzy inference system. Modelling uncertainty provides additional information which can assist in a further risk analysis for exploration decision making. 相似文献
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在概述我国金属矿产资源研究、勘探开发所面临新的形势、任务和挑战的基础上，介绍了澳大利亚从事金属矿产研究、勘探开发的主要机构，介绍了澳大利亚与金属矿产资源研究、勘探开发有关的重大研究计划、研究中心、找矿新技术方法，总结了澳大利亚金属矿产资源研究、勘探开发的现状、特色以及对我国矿产资源工作的启示意义。 相似文献
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Arthur W. Rose 《Journal of Geochemical Exploration》1982,16(3):163-182
Data on copper reserves, recent discovery rates, and historical tonnage-grade relations indicate that the U.S. can be approximately self-sufficient in copper to the year 2000 by mining grades similar to those presently being mined, and given reasonable exploration efforts, the U.S. can supply its demand for about 100 years by mining inferred tonnages above 0.1% Cu. However, recent price trends and the increased cost of mining lower grade ore will increase the price of copper at a rate faster than the general inflation rate, and may lead to significant imports because of their cheaper price.Compilation of the discovery history for copper shows that the Hubbert Gaussian curve is not applicable to predict copper reserves, and may not be applicable for other commodities.A compilation of the value of base and precious metal deposits discovered since 1940, along with meager data on cost and manpower used in exploration, indicates very little decrease in exploration effectiveness over the 40-year interval, in contrast to oil and uranium. Collection of better data on expenditures for metallic mineral exploration is recommended. 相似文献
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Vegetation sampling is an effective mineral exploration technique in areas of transported cover in the Tanami Gold Province where other techniques have been of limited success. This research tests the ability of plants to show signatures of mineralisation as well as the optimum scale of sampling for first-pass mineral exploration surveys. The semi-arid Tanami Gold Province in northern Australia encompasses nearly 160,000 km2 and is a highly prospective yet under-explored region due to transported cover masking mineralisation. Various dominant plant species were sampled along transects across four sites of Au mineralisation in the Tanami (Larranganni, Hyperion, Coyote and Titania). Snappy gum (Eucalyptus brevifolia) gave a geobotanical (plant distribution) and lithological (S and Zn) signature of an underlying geological structure known to host Au mineralisation at the Coyote Prospect. Soft spinifex (Triodia pungens) provided an Au, As, ± Zn, ± S, and ± Ce expression of buried Au mineralisation at Coyote and Titania. At the Hyperion prospect, mineralisation is located at the contact between granite and dolerite, and biogeochemical signatures from snappy gum and dogwood (Acacia coriacea) show elevated ± Au, Ce, S and Zn that corresponded to the contact. Biogeochemistry is able to determine the location of mineralisation at each site, except at Hyperion where the sample density was too low. It is able to identify underlying substrate differences, however, background knowledge relating to regolith, geology, hydrology and geophysics are important in aiding the interpretation of the elemental data. It was found that having too few samples (at Hyperion) there was insufficient useful information for mineral exploration. Grid coverage of an area (at Titania) provided information on mineralisation and groundwater dispersion plumes; however, in this case a single transect over the same area would have been sufficient for a first-pass mineral exploration survey. 相似文献
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Vast parts of the Australian continent are prospective for precious and base metal mineralisation, but exploration is hindered by extensive cover of often deeply reaching regolith. New operational exploration methods are required that can help to characterise the cover and provide information about bedrock signatures. This paper shows how mineral mapping information from a combination of satellite multispectral Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery and drill core hyperspectral profiling data (HyLogging™) can be used to unravel the regolith stratigraphy and to describe regional variations of regolith landforms, delivering important information for mineral exploration.The case study is located in the Neale tenements in the northeastern Albany–Fraser Orogen (Western Australia), which is prospective for Tropicana-style gold mineralisation. By interpretation of indicator minerals from hyperspectral drill hole logging data the regolith stratigraphy atop a metamorphic basement, comprising saprock, ferrugineous saprolite, kaolinitic saprolite, silcrete and transported cover, is recorded in cm-detail. Important mineralogical parameters extracted from the hyperspectral subsurface data and validated by XRD and FTIR, are 1) the abundance and type of iron oxides, 2) the abundance and crystallinity of kaolinite, 3) the abundance and composition of primary minerals, such as white mica, and 4) the abundance of quartz.The HyLogging™ data served as ground control points for mineral mapping information provided by CSIRO's ASTER Geoscience Products, which are a collection of mineral maps that highlight variations in the abundance, type or chemistry of selected mineral groups. Key ASTER Geoscience Products for regolith characterisation were the Ferric Oxide and AlOH abundance and composition images. The comparison of the surface with the subsurface data suggests three major different regolith landforms, including erosional, depositional and relict areas, which were used to generate a map showing transported versus relict and erosional areas. Erosional domains were mapped out in great detail, providing important information for exploration in saprolite dominated areas. Furthermore, source areas of transported material could be identified, which may help to understand the distribution of geochemical signatures collected during, for example, geochemical soil sampling projects. 相似文献
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The clustering of mineral occurrences and their spatial associations with particular geological features are critical aspects of mineral distributions for exploration and understanding ore genesis. Variations in the degree of clustering of mineral occurrences or geological features can be measured by fractal dimensions, obtained from a shifting box counting method. Spatial associations between mineral occurrences and geological features can be quantified by the weights of evidence (WofE) method using the contrast value, which increases with the strength of the spatial relationship. A new method is proposed to evaluate mineral occurrence distributions by combining the power of fractal analysis of clustering with the WofE approach. The method compares the correlation between the variation in degree of clustering of mineral occurrences and a geological feature in a study area, with the contrast value of the same feature. The possible outcomes can be simplified into four scenarios, depending on whether the correlation in variation of clustering and the contrast are high or low, respectively. Each outcome has specific exploration implications. If either a high correlation in variation of clustering or a high contrast value is obtained, the geological feature can be used for exploration targeting.The integrated fractal and WofE approach is applied to copper occurrences in the Proterozoic Mount Isa Inlier, NW Queensland, Australia, which hosts large numbers of copper deposits (1,869 occurrences), including the world class Mount Isa copper deposit. Variation in clustering of copper occurrences has a positive correlation with variation in clustering of fault bends (R = 0.823), fault intersections (R = 0.862) and mafic rocks (R = 0.885). WofE results indicate that the copper occurrences are spatially associated with fault intersections and bends and with mafic rocks. Analyses were carried out separately for the two major lithostratigraphic sequences in the Inlier, the Eastern and Western Successions. The Western Succession copper occurrences are apparently more clustered than those of the Eastern Succession, which may reflect a lower degree of exploration and/or geological factors. The association of copper occurrences with mafic rocks compared with fault bends and intersections is greater in the Eastern Succession, which may reflect genetic factors. Correlations in the variation of clustering of mineral occurrences and geological features have a linear relationship with the contrast values, and the spatial association between all geological features and copper occurrences constitute high correlation/high contrast cases. The linear relationship suggests that the geological features that control the clustering of the copper occurrences could be the same features that control their localization. 相似文献
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概述了乐山建材非金属矿产资源的主要特征，阐明了其勘查与开发利用现状，并对资源形势作了分析，进而论述勘查与开发利用的前景。 相似文献
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