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| 1 | Variations in carbon isotopic composition in the subcontinental lithospheric mantle beneath the Yangtze and North China Cratons:Evidence from in-situ analysis of diamonds using SIMS显示文摘The components and evolution of subcontinental lithospheric mantle beneath the North China Craton and the Yangtze Craton is a current topic in the geological study of China and the carbon isotopic composition of diamond is one of the most direct probes into cratonic lithospheric mantle processes.In this paper,in-situ SIMS(Secondary Ion Mass Spectrometry) techniques were used to analyze the carbon isotope compositions at different internal growth zones of diamonds from Shandong and Liaoning in the North China Craton and Hunan in the Yangtze Craton.It was found that the carbon isotopic range of diamonds from the North China Craton are rather distinct from those of the Yangtze Craton;the former has a range of 6.0‰ to 2.0‰(relative to VPDB) with an average value of 3.0‰ in their core areas,which is consistent with global peridotitic diamonds;the diamonds from the Yangtze Craton,however,have a carbon isotopic range from 8.6‰ to 3.0‰ with an average value of 7.4‰ in their core areas,being more consistent with global eclogitic diamonds.The variations of carbon isotope ratios between different internal growth zones in individual diamonds were different in the three diamond localities studied.There was a clear correlation between changes in carbon isotopic composition and phases of diamond dissolution and new growth,while no correlation was observed between δ13C and internal inclusions.The variations suggest that the carbon isotopic compositions of mantle fluids were changing during the process of diamond crystallization,and that the heterogeneity of the carbon isotopic composition in mantle carbon reservoirs was a more important factor than carbon isotope fractionation in controlling the carbon isotopic compositions and their variation in diamonds.In addition,the preliminary results of in-situ nitrogen analyses demonstrated that the variation of carbon isotopic compositions between the core and outer growth zones does not correlate with nitrogen abundances,implying either that diamonds crystallized in an open environment or that the carbon isotopic composition and nitrogen contents in mantle fluids were controlled by other,not yet understood factors.The experimental results provide hints that the isotopic composition of carbon and its original sources were different in metasomatic fluids controlling diamond formation in the mantle beneath the North China Craton and the Yangtze Craton. | CHEN Hua QIU ZhiLi LU TaiJin STERN Richard STACHEL Thomas SUN Yuan ZHANG Jian KE Jie PENG ShuYi QIN SheCai | 2013 | Chinese Science Bulletin2013，58，1： | 7 |
| 2 | 在珠宝首饰界准确鉴定宝石的重要性显示文摘在当今珠宝首饰市场上,无论是优化处理的还是合成的宝石材料,其种类和数量都在增加。在某些情况下,它们呈现出与贵重天然宝石极其相似的外观特征。尽管某些经处理的或合成的宝石材料常显示出其独特的宝石学性质,但对于珠宝商,尤其是对那些缺乏宝石学专业培训或刚刚入门使用常规宝石鉴定方法或设备的珠宝商,鉴定起来十分困难。因此,到专业宝石鉴定实验室去鉴定宝石样品就显得非常必要。在专业实验室中,先进的科学仪器必须由受过培训的专业人员操作。宝石的准确鉴定对维护天然宝石的商业价值及消费者的信心都至关重要。目前大多数宝石学研究的目的是给珠宝首饰商及宝石学家提供可操作的宝石鉴定手段,以有助于确保国际宝石市场的完整性。介绍了几种优化处理及合成宝石材料的鉴定实例,这些材料对当今的宝石鉴定提出了挑战。 | James E.Shigley Taijin Lu Wuyi Wang 张辉 | 2004 | 宝石和宝石学杂志2004，6，2： | 7 |
| 3 | Amber with mineral inclusions 显示文摘 | Li Haibo Lu Taijin Shen Meidong | 2010 | Gems & Gemology2010，46，4： | 1 |
| 4 | Open channels in near- colourless synthetic moissanite显示文摘 | Lu Taijin Shigley J E Koivula J I | 2002 | Journal of Gemmology2002，28，3： | 1 |
| 5 | Spectroscopic Features and Coloration of Gem-Quality Green Tsavorite in Major International Deposits and China显示文摘Tsavorite green colored by Cr3+/V3+ has been traditionally found and mined in Tanzania, Kenya and Madagascar in the Neoproterozoic Mozambique metamorphic belt (NMMB), and recently be found in Sanjiang, Litang, Sichuan, China. The differences of the chemical formula, spectroscopic features, as well as the concentrations of the V2O3 and Cr2O3 in the tsavorite crystals collected from major international deposits and Sanjiang, China have been investigated using EPMA, XRF, UV-VIS spectrometers, FTIR, Raman scattering microscopy, DiamondView TM techniques. It was found that the chemical formulas of African tsavorite and Chinese tsavorite are Ca3(Al,V)2[SiO4]3 and Ca3(Al,Cr)2[SiO4]3, respectively, indicating that tsavorite is a solid solution between dominant grossular and minor goldmanite and uvarovite. Two broad bands centered at 430 nm and 605 nm were the main absorption features in the tsavorite samples, which attribute to the absorption of Cr3+ and/or V3+ ions in the lattice. The green coloration is caused by Cr3+ and/or V3+ ions resulting in the absorption of purple and red components of the visible light. Absorptions caused of Fe3+ and Fe2+ ions could add the bluish color component in some of tsavorite samples. The intensity of green color is proportional to the concentrations of V2O3 and Cr2O3. The basic gemological properties, such as refractive index in the investigated samples were presented, and the definition and chemical and spectroscopic properties of tsavorite are discussed. | L Linsu ZHANG Yong LI Hongbo LU Taijin MAO Bing CHEN Hua | 2013 | 矿物学报2013，33，S1： | 0 |
| 6 | Coal-Forming Model in the Context of Non-marine Sequence Stratigraphy:A Case Study of Jurassic Coal Measures in Northern Qaidam Basin,Northwestern China显示文摘Previous studies of coal sequence stratigraphy have concentrated on coals associated with paralic depositional systems.Little attention has been paid to their counterparts in non-marine intra-mountain coal basins.The northern Qaidam Basin of northwestern China has been extensively developed with abundant oil and gas as well as coal resources in its Jurassic non-marine successions.A total of six sedimentary systems of the Early and Middle Jurassic | Jing Lu~1,Longyi Shao~1,Taijin Liu~2,Qi Ju~2,Huaijun Wen~2,Hao Wang~1 1.Department of Resources and Earth Sciences,China University of Mining and Technology(Beijing),Beijing 100083,China. 2.Qinghai Administration of Coal Geology,Xining 810000,China | 2009 | 地学前缘2009，16，S1： | 0 |
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