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1.
O. R. Eckstrand 《Mathematical Geology》1977,9(3):235-243
The Geological Survey of Canada (G.S.C.) has been involved in national appraisal of resources of certain commodities for nearly two decades beginning with a national study of iron deposits in 1955. In 1972, the first national appraisal to rapidly estimate total resources of Cu, Pb, Zn, Ni, Fe, Mo, and U in Canada was carried out largely by economic geologists. This exercise produced, among other things, a better definition of G.S. C. needs for building computer files in support of mineral deposits studies and mineral resource appraisal. Objectives of this paper are threefold: (1) to outline general methodology for the kind of mineral resource appraisal carried out by the G.S.C. in 1972; (2) to identify types of information required in that appraisal; and (3) to indicate types of information on mineral deposits for which it seems advantageous for the G.S.C. to construct computer files, and how these files relate to mineral resource appraisal. Methodology is fairly straightforward for appraisal of reserves (known, measured resources), but is much more problematic for appraisal of undiscovered resources. For the latter, G.S.C. economic geologists make use of two basic concepts: the deposit model, which is a generalized deposit type, distinguished by its geological attributes and host rock environment, and containing characteristic amounts of specified commodities; and the metallogenic region, which is a geographic area of more or less homogeneous geology deemed favorable for the presence of a particular deposit model. Background information required for appraisal of undiscovered resources includes the following: (a) data on distribution and geology of Canadian deposits and occurrences; (6) data on geology of important, foreign deposits; (c) knowledge of Canadian geology, commensurate with metallogenic requirements; (d) knowledge of current theories of ore-forming processes; and (e) appreciation of the amount, location, and effectiveness of past exploration in Canada. At present, only identity, location, and certain simple geological features of Canadian deposits are considered practical for a general computer file of mineral deposits. The fundamental activity of the G.S.C. in the sphere of mineral deposits is a number of broad studies on the geology of certain commodities in Canada carried out by economic geologists. Appraisal of mineral resources is based directly on the results of those studies, and is done by the same economic geologists. Construction of G.S.C. computer files is in response to needs defined by economic geologists, mainly in the context of their broad studies.This paper was presented at the International Geological Correlation Program (IGCP) Project 98 entitled Standards for Computer Applications in Resource Studies held at Loen, Norway, September 27–October 1, 1976. 相似文献
2.
The problem of incorporating the available seismological information provided by the major events of the historical catalog with those for the short period of instrumental data is investigated. Assuming that the frequency-magnitude law of Gutenberg and Richter is valid for both periods, an estimation procedure for the main parameter of this law and the rate of earthquake occurrence for historical period is presented. Application of the proposed method is demonstrated, using both real and simulated data. An extension to allow for variable quality of complete data with different magnitude values is also included. 相似文献
3.
《寒旱区科学》2014,(4):I0002-I0003
1. Aims and scope
Sciences in Cold and Arid Regions (SCAR) is a bimonthly journal that publishes in English the latest research achievements in processes and the pattems of the Earth surface system in cold and arid regions. Researches in cold regions emphasize particularly on the cold-region-characterized physical, 相似文献
Sciences in Cold and Arid Regions (SCAR) is a bimonthly journal that publishes in English the latest research achievements in processes and the pattems of the Earth surface system in cold and arid regions. Researches in cold regions emphasize particularly on the cold-region-characterized physical, 相似文献
4.
《中国海洋大学学报(英文版)》2014,(3):I0001-I0001
<正>The Journal of Ocean University of China(Oceanic and Coastal Sea Research)is a comprehensive academic quarterly sponsored by the Ocean University of China,published one volume per year.This journal is devoted to the publication of the theoretical and applied research 相似文献
5.
对2006-2009年两种途径(A文件和Z文件)上传的2400多国家级自动站观测的小时常规六要素资料进行了对比分析。结果表明:两种途径得到的小时数据中,2 min风和10 min风的不一致率较高,主要由两种文件对于风速为零时风向的规定不同造成,其他要素的不一致率相对较低;在不一致数据中,各要素在仪器误差允许范围内的比率分别为气温23.27 %、气压5.4 %、相对湿度23.19 %、降水65.42 %、2 min风12.93 %、10 min风14.16 %。 相似文献
6.
为满足气象实时资料传输中大量气象数据小文件的高时效传输需求,对其中的数据传输服务进行优化,提出一种基于实时网络状况的自适应数据传输优化方法。该方法采用优化网络传输协议并使用文件压缩技术,通过获取网络传输线路上的实时参数,实时调整压缩参数和网络传输参数以优化传输性能。在自适应压缩时,通过试验分析和归纳,确立了气象数据小文件标准为文件小于50 KB;根据网络实时状况,设计了基于实时网络状况自适应调整压缩等级的算法。在自适应传输参数调优中,研究了TCP缓冲区大小和TCP并发连接数在GridFTP协议中的重要性,针对实时网络状况,分别设计了自适应调整TCP缓冲区大小和TCP并发连接数的算法,算法提升传输性能65%。对以上提出各自适应参数调整算法进行试验验证表明,融合压缩和网络传输的自适应调优方法能显著提升气象小数据文件的传输性能近500倍。 相似文献
7.
《地学前缘(英文版)》2014,(3):I0001-I0003
正1 AIM AND SCOPE GEOSCIENCE FRONTIERS(GSF) is a bi-monthly international journal that publishes in English high quality original research articles and timely reviews in interdisciplinary fields of Earth and Planetary Sciences.GSF aims to bridge innovative,provocative and challenging concepts and models related to various fields of research including petrology and geochemistry in understanding lithospheric architecture 相似文献
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10.
《The Professional geographer》1989,41(4):494-501
Software Reviews are in this Article CCS Designer Version 3.0. CoStat Version 3.03; CoPlot Version 1.03, and CoDraw Version 1.03. LASERCAD Version 5.0. 1988. SPSS/PC + Studentware. 1988. SURVEY SYSTEM 1.1C , Version 3.0. THEMAPS Version 1.0. 相似文献