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81.
受海拔高、空气稀薄、气候无常、高差较大等自然条件的影响,高海拔地区进行测量作业与低海拔地区有很大差别。根据高海拔地区矿山特点,结合多年矿山控制测量、特别是高海拔矿山控制测量经验,讨论在高海拔地区矿山因地制宜地建立测量控制网的方法。 相似文献
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石平川钼矿由燕山晚期第四次侵入碱性长石花岗岩体提供物源和热动力,火山机构、断裂和西山头组第二岩性段为成矿提供了导矿通道和容矿场所。 相似文献
84.
P. de Caritat P. T. Main E. C. Grunsky A. W. Mann 《Australian Journal of Earth Sciences》2017,64(8):1033-1043
Understanding the character of Australia's extensive regolith cover is crucial to the continuing success of mineral exploration. We hypothesise that the regolith contains geochemical fingerprints of processes related to the development and preservation of mineral systems at a range of scales. We test this hypothesis by analysing the composition of surface sediments within greenfield regional-scale (southern Thomson Orogen) and continental-scale (Australia) study areas. In the southern Thomson Orogen area, the first principal component (PC1) derived in our study [Ca, Sr, Cu, Mg, Au and Mo at one end; rare earth elements (REEs) and Th at the other] is very similar to the empirical vector used by a local company (enrichment in Sr, Ca and Au concomitant with depletion in REEs) to successfully site exploration drill holes for Cu–Au mineralisation. Mapping of the spatial distribution of PC1 in the region reveals several areas of elevated values and possible mineralisation potential. One of the strongest targets in the PC1 map is located between Brewarrina and Bourke in northern New South Wales. Here, exploration drilling has intersected porphyry Cu–Au mineralisation with up to 1 wt% Cu, 0.1 g/t Au, and 717 ppm Zn. The analysis of a comparable geochemical dataset at the continental scale yields a compositionally similar PC1 (Ca, Sr, Mg, Cu, Au and Mo at one end; REEs and Th at the other) to that of the regional study. Mapping PC1 at the continental scale shows patterns that (1) are spatially compatible with the regional study and (2) reveal several geological regions of elevated values, possibly suggesting an enhanced potential for porphyry Cu–Au mineralisation. These include well-endowed mineral provinces such as the Curnamona and Capricorn regions, but also some greenfield regions such as the Albany-Fraser/western Eucla, western Murray and Eromanga geological regions. We conclude that the geochemical composition of Australia's regolith may hold critical information pertaining to mineralisation within/beneath it. 相似文献
85.
《Marine Policy》2014
Stakeholder participation is vital when introducing and implementing ecosystem-based management (EBM) at any scale. This paper presents the results of a survey covering four European Regional Seas (Baltic Sea, Black Sea, Mediterranean Sea and North-East Atlantic Ocean) aimed to collect stakeholders׳ perspectives on their Regional Sea governance to implement the European Union (EU) Marine Strategy Framework Directive (MSFD). In this survey, drivers of good governance including stakeholder involvement, willingness and capacity to cooperate, efficiency, institutional ambiguity and decision-making were explored. The results indicate a clear gap in perception between the current, the ideal and the foreseen situation regarding the implementation of the MSFD. The preferences for the future governance structures vary between stakeholders and across seas although some similarities can be found. Based on the results of the survey, this paper concludes that tailor-made rather than off-the-shelf solutions will be needed to accommodate regional cooperation in the European marine environment for implementing ecosystem-based management under the MSFD. 相似文献
86.
云南宣威羊场煤矿资源潜力评价 总被引:1,自引:0,他引:1
羊场煤矿经50年开采,资源近于枯竭。通过地质调查和预测,提供可靠依据,为危机矿山新增储量,延长矿山服务年限。 相似文献
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The archival papers of the eminent petrologist Alfred Harker span his entire geological career of over 60 years. These are held by the Archive of the Sedgwick Museum of Earth Sciences (University of Cambridge). Harker was associated with the Department of Geology, the Woodwardian Museum and post-1904, the Sedgwick Memorial Museum. Importantly, his meticulously labelled notebooks provide an unprecedented insight into his development as a field and laboratory scientist. They chart Harker's beginnings as a fossil collector and observer of sedimentary stratigraphy on the North Yorkshire coast, his trips to Wales and Devon with the Sedgwick Club, and his later work in the English Lake District with his friend and colleague John. E. Marr. This paper examines in particular Harker's suite of 20 notebooks kept up until 1894, including his trip to Edinburgh in August 1892. This visit introduced the young scientist to the geology of Scotland for the first time. An overview of Harker's experience and contemporary contacts suggests some reasons why Sir Archibald Geikie later invited him to join the Scottish Survey staff in 1895. 相似文献
89.
The regulation of minimum legal size (MLS) of catches is a tool widely applied in the management of fisheries resources, although the MLS does not always coincide with the length at first maturity (LFM). The optimization of this management tool requires a series of quality control in fish markets and transportation. A software application has been developed to make the control of the landings of several target species easier and faster. In order to test and make this tool operational, six species of commercial interest were selected: four species of fish and two species of bivalves. It is proposed to estimate the proportion of illegal specimens in the studied lot from the proportion of illegal individuals found in the samples taken from this lot. The input data for the application are the minimum legal size (MLS) of the species and the total length (TL) of each specimen sampled. The output data is a statistical summary of the percentage of specimens of size less than the legal minimum (TL≤MLS) within different confidence intervals (90%, 95% and 99%). The software developed will serve as a fast, efficient and easy to manage tool that allows inspectors to determine the degree of compliance on MLS control and to make a decision supported by statistical proof on fishing goods. 相似文献
90.