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本文介绍了彩色钻石的概念,论述了其特点、分类。据彩钻的色度深浅将彩色(以红、绿、蓝、紫、粉为例)详细分为15级:微、弱、浅、浅淡、淡、淡中、深淡、中、中彩、彩、浓彩、浓、深、极深、暗,简化后分8级:弱、浅、淡、中、彩、浓、深、暗。关于彩色钻石的明亮度详细划分为8级:很暗、暗、较暗、较明、明亮、亮、亮彩、阳亮。简化为4级:暗、较明、明亮、阳亮。颜色色种的稀有度分级有:顶端稀有色种的红色系,极度稀有色种的绿色系、橙色系、紫色系,稀有色种的蓝色系、粉色系,较稀有色种的棕色系、黑色,少见色种的灰色系、褐色系,较少见色种的黄色系。文中对彩钻大小的粒度也进行了界定,并对彩钻的致色因素做了探讨,分作岩浆期致色、岩浆期后致色、未知的复杂因素致色等。指出了彩钻所包含的研究领域。 相似文献
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《水文地质工程地质》2013,(1):8
1月3日,我国著名水文地质学家、中国科学院院士、《水文地质工程地质》主编陈梦熊遗体告别仪式在北京八宝山革命公墓举行。国土资源部部长、党组书记、国家土地总督察徐绍史,国土资源副部长、党组副书记、国家土地副总督察、国家测绘地理信息局局长徐德明,国土资源部党组成员、副部长汪民、张少农、王世元、胡存智,国土资源部党组成员、 相似文献
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由中国工程院、国土资源部、中国科学院、中国航天科技集团公司主办的"月球与火星探测科技高层论坛",于2011年10月18—20日在北京举行。来自中国工程院、国土资源部、中国科学院、中国航天科技集团公司、教育部、国家测绘地理信息局、中国地质科学院、澳门科技大学、香港科技大学、中国地质大学、北京大学、清华大学、南京大学、吉林大学、复旦大学、美国华盛顿大学(圣路易斯)、康奈尔大学、 相似文献
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激光剥蚀-电感耦合等离子体质谱准确测定锆石中钛的含量 总被引:2,自引:2,他引:0
外标物质及内标元素的选择是激光剥蚀-电感耦合等离子体质谱(LA-ICP-MS)准确测定元素含量的关键因素之一。文章选用玻璃标准参考物质NIST 610、GSE-1G、BHVO-2G、BCR-2G、ATHO-G、KL2-G和T1-G作为外标,Si或Zr作为内标,对锆石M257中的Ti进行LA-ICP-MS微区原位测定。结果显示,选择Si或Zr作内标,采用BCR-2G、ATHO-G、KL2-G和T1-G作外标时,Ti含量测定值与参考值之间差异均较大,因此它们不适合作外标物质。采用BHVO-2G作外标和Si作内标,NIST 610作外标和Zr作内标,Ti含量测定值与参考值之间的差异均小于4%,因此BHVO-2G和NIST 610可有条件地作为外标物质。选择Si还是Zr作内标,GSE-1G作外标时,Ti含量的测定值与参考值之间的差异均小于3%,说明GSE-1G是较为合适的外标物质。选用GSE-1G作为外标,Si作内标,对5个标准锆石中的Ti含量进行了测定,结果显示,Ti元素在锆石91500中分布不均匀,而在锆石GJ-1、M257、PENGLAI和MUDTANK中分布均匀。在Ti元素分布均匀的GJ-1、M257、PENGLAI和MUDTANK等4个锆石中,由于Ti的含量均小于5μg/g,不适合作为锆石中Ti元素测定用的外标物质,但可作为测定时的质量监控样品。 相似文献
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滇池流域石漠化特征分析 总被引:2,自引:2,他引:0
位于云南省会昆明盆地内的滇池流域是滇中岩溶和石漠化较为发育的地区,石漠化总面积225.56 km2,占流域总面积的7.71%,占岩溶总面积32.69%。石漠化主要分布在望海山、大板桥—呈贡、黑林铺、海口、梁王山、上蒜片区,其中又以北东部的大板桥片区石漠化最为严重。石漠化已造成流域内水土流失加剧、可耕地面积减少、土壤涵养水源能力降低及生态环境恶化等危害。通过地面调查和ETM遥感解译,查清了流域内石漠化的发育分布与碳酸盐岩的岩性及其组合、岩溶作用、地形地貌、气象等自然因素、人为因素和工业污染关系密切。针对石漠化的形成原因,提出了生态修复、农田基本建设、水资源开发利用、农村能源建设、小集镇建设、土地合理利用等治理措施。 相似文献
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本文采用电子探针、透射电镜和化学物相法,查明某古岩溶铀矿床中铀主要呈显微和超显微状沥青铀矿、铀石,其次呈分散吸附状和铀酰(次生)矿物形态存在;钼主要呈蓝钼矿、钼钙矿、钼华、钼铅矿等氧化物,其次呈胶硫钼矿等形态存在;铼主要呈吸附状,其次可能在黄铁矿中呈二硫化物包裹体形态产出。最后讨论了该三个元素赋存状态与该铀矿床形成地球化学环境之间的关系。 相似文献
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《水经注》中有关北京地理的科学思想 总被引:1,自引:0,他引:1
《水经注》是我国古代著名的地理学著作之一,作者郦道元是北魏时期范阳(涿州—北京)人,因此书中对北京附近的水系和地理情况进行了描述。书中称拒马河为巨马水、大石河为圣水、永定河为漯水、清水河为清夷水、温榆河为湿馀水、潮白河为鲍邱水、泃河为泃水,称永定河出山段为清泉河、流经北京城内的什刹海和中南海为高粱河。对家乡附近的地理进行了描述,称房山为大房岭、石景山为梁山,记录了昌平县、密云戍、平谷县等行政区域,记录了羊头埠(羊头岗)、马兰(马栏)、芹城(秦城)、独乐水(独乐河)、良乡、居庸关、盘山等地名。记录了中国最早的首都——涿鹿,记录了中国现代首都蓟城(北京)内曾有蓟丘,说明永定河沟通了古今首都。记录了北京最早的水利工程戾陵堰和车箱渠。 相似文献
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《Geoforum》2016
This introduction to the themed issue discusses the articulation of protected areas, conservation, and security in issue contributions. Protected areas are presented as localized sites to address global crises, such as anthropogenic climate change and the “war on terror.” When they are sites for securitization and militarization, protected areas articulate state and subject formations through violence. As threat discourses have amplified in recent years, communities once deemed putative eco-destroyers have been interpellated as potential threats in wars on drugs and/or terror. The themed issue reveals that reframing environmental crime as organized crime has significant implications for expanding claims of what counts as legitimate use of force in protected areas policing, as well as potential prosecutions. It is apparent that security for one group may hinge on the insecurity of another group at different historical and political moments. In this special issue we challenge conservation actors as well as those critical of conservation to ask: for whom does conservation provide security, under what circumstances, and at what cost? 相似文献
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Lü Delin 《中国地质大学学报(英文版)》2001,12(4)
Since Dow (l972) proposed the concept of oil system atthe AAPG annual meeting in l972, after unremitting effol.tsand progressive perfection, it has become the petroleum systemaccepted by numerous geologists at present. The concept of pe-troleum system was introduced to our country in early l990s(I)ou, l999). In fact, as early as the 1960s, based on the hy-drocarbon exploration and development practice at Songliao ba-sin and Bohai Bay basin, some viewpoints similar to petroleumsystem have be… 相似文献
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Barbara Romanowicz 《Comptes Rendus Geoscience》2003,335(1):23-35
We present an overview of the present knowledge of the Earth's lower mantle 3D structure, as currently obtained owing to progress, in the last ten years, in seismic tomography as well as forward modelling of seismic travel times and waveforms. We discuss constraints that seismic modelling brings to the debate concerning major geodynamical questions, in particular the issue of global ‘1 layer’ or ‘2 layer’ circulation, of the missing geochemical reservoir, as well as of the role in global dynamics of the thermochemical boundary layer at the base of the mantle. 相似文献
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《International Geology Review》2012,54(11):1622-1627
Variations in the Ag:Au ratio are discussed, as in halos of ores in the Baley goldfield, across the strike of ore bodies, as well as up-dip. The results bring out spatial zonations in the halos. Attention is called to the usefulness of the ratio in ascertaining migration paths of the hydrothermal solutions, microstructures of the halos, forms of the elements, as well as in prospecting for the ores. — Authors. 相似文献
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Günther Weiss 《Geoforum》2008,39(1):20-31
Particularly in view of the general trend for governments to withdraw from environmental regulation and leave the field to market processes, and in view of the growing importance of (transnational) environmental NGOs, the question arises whether and to what extent the local level as a location for production activities of whatever kind may influence the environmental performance of industrial enterprises. The concept proposed for the local level in this study incorporates the business-cluster and the (creative) milieu approach. The study uses disputes about the pulp industry in Germany in the period between 1950 and 2005 as an example to investigate the influence of local actors and local knowledge. It appears that the perception of industry-related environmental problems, as well as the solutions proposed, increase in quality as the volume of localised industry-specific knowledge expands. At the same time, responses at the local level are unmistakeably informed by debates about environmental problems on the national plane as well as by discussions about development paths at the local and/or regional level. 相似文献