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81.
82.
中国大陆科学深钻主孔岩屑中含钠和锌的尖晶石的发现 总被引:1,自引:0,他引:1
一种含钠和锌的尖晶石矿物产于中国大陆科学深钻主孔超镁铁岩中,以出溶的方式存在于钛铁矿和磁铁矿中,长5-60μm,宽2-3μm,化学组成(wB%)为MgO17.143%-22.337%,Al2O3 63.646%~66.492%,FeO9.784%~13.924%,ZnO 1.649%-6.386wt%.Na2O 0.029%~0.219wt%。Na2O与ZnO在尖晶石中的含量呈正相关关系。经同步辐射测得其为尖晶石单晶,空间群为Fm3m,晶胞参数为a=0.83781am。根据尖晶石与钛铁矿、石榴石(pyr=56-58mol%)共生和石榴石退变为顽火辉石和镁绿泥石的特点,表明该尖晶石来自超镁铁岩,它们一起经历了至少为角闪岩相的变质作用。广泛的混溶间断现象及其所造成的出溶结构出现在氧化物中,表现为Mt-Usp、Mt-Spl及Mt-Ilm之间的交生。根据前人有关Mt-Usp和Ilm-Gk-Hem固溶体系的实验。表明主孔岩石的氧逸度相对较低,形成温度应在720℃以上。这些早期在岩浆分离结晶过程中形成的铁钛氧化物出溶体,在后来的超高压变质作用下可能发生再次固溶和因降温减压造成的出溶。 相似文献
83.
对Li-(Mg、Zn、Ni)钒酸盐系统在500—800℃的相图研究发现:(Mg、Zn、Ni)V_2O_6和(Mg、Zn、Ni)_2V_2O_7,二个系统中都有两个主要固溶体,一个以NiV_2O_6(或Ni_2V_2O_7)为主结构,另一个在MgV_2O_6-ZnV_2O_6间形成完全连续型,Mg_2V_2O_7-Zn_2V_2O_7间为MgZnV_2O_7结构型。(Mg、Zn、Ni)_3V_2O_8系统中,整个就是一个固溶体,而Li(Mg、Zn、Ni)VO_4系统中,端员组分相互间也形成不同的固溶体。 相似文献
84.
Tiexin Gu Wei Bu Weidong Yan Changyi Shi Mingcai Yan 《Geostandards and Geoanalytical Research》2003,27(2):193-196
Sulfide mineral certified reference materials GSO 1-7, recently prepared by the Institute of Geophysical and Geochemical Exploration (IGGE), were analysed by twelve laboratories. Various reliable analytical methods based on different principles were adopted and classical chemical methods were taken as the primary analytical methods, by which 5729 determinations were carried out, 1425 average data were obtained, and twenty one to twenty seven elements and components were certified. 相似文献
85.
湖南锡铅锌资源丰富,保有储量列全国第四位,是我国重要的锡铅锌矿工业基地之一,锡铅锌矿业对满足省内外消费需求、促进出口贸易、创造就业机会及发展相关产业起着十分重要的作用.然而,湖南锡铅锌资源保证程度不高,现有锡铅锌保有储量保证年限均在10a以下,很难满足日益增长的国内外需要.作者认为采取“合理部署国土资源大调查工作,加强老矿山周边及深渐找矿工作,建立矿业权市场、加大地勘投入,努力提高资源综合利用水平”等措施可应对社会经济可持续发展对锡铅锌勘查的挑战. 相似文献
86.
Akio Makishima Katsura Kobayashi Eizo Nakamura 《Geostandards and Geoanalytical Research》2002,26(1):41-51
A simple and accurate method for the determination of Cr, Ni, Cu and Zn at μg g?1 levels in milligram‐sized bulk silicate materials is reported using isotope dilution high‐resolution inductively coupled plasma‐mass spectrometry (HR‐ICP‐MS) with a flow injection system. Silicate samples with Cr, Ni, Cu and Zn spikes were digested with HF‐HBr and Br2, and subsequently decomposed at 518 K in a Teflon bomb. In this procedure, all sulfides and chromite, major hosts of these elements, were completely decomposed, thus allowing for isotope equilibration between the sample and spike. Magnesium and Al fluorides formed after the digestion of the sample were removed by centrifugation, and the supernatant was directly aspirated into a HR‐ICP‐MS at a mass resolution of 7500, where interfering oxide ions, ArO+, CaO+, TiO+, CrO+ and VO+, were separated from Cr+, Ni+, Cu+ and Zn+. No matrix effects were observed down to a dilution factor of 50. Detection limits for these elements in silicate samples were < 0.04 μg g?1. The effectiveness of the technique was demonstrated by the analysis of 13 to 40 mg test portions of USGS and GSJ silicate reference materials with a major element composition ranging from andesite to peridotite, in addition to 8‐23 mg of the Smithsonian reference Allende. Both the reproducibility and the deviation from the reference value for most reference materials of various rock types were < 9%, and thus confirm that the method gives accurate analytical results for small sample sizes over a wide range of Cr, Ni, Cu and Zn contents. This method is, therefore, suitable for analysing small and/or precious bulk samples, such as meteorites, mantle peridotites and mineral separates, and for the characterisation of silicate and sulfide minerals for use as calibration samples in secondary ion mass spectrometry or laser ablation ICP‐MS. 相似文献
87.
采用盆栽试验,初步研究了干旱区绿洲土壤—胡萝卜系统中镉、锌、镍3种重金属的形态变化特征及其生物有效性问题。结果表明:供试绿洲土壤原状土中,Cd、Zn、Ni均以稳定的残渣态形式存在,而处理土壤中重金属被钝化的量有限,Cd的存在形式主要以碳酸盐态为主,Zn、Ni则主要以铁锰氧化态为主;3种元素的活性大小依次为Cd>Ni>Zn。根据回归分析,元素Zn对胡萝卜块茎和茎叶吸收Zn量贡献最大的分别是Zn的碳酸盐结合态和铁锰氧化态;元素Ni对胡萝卜各部位吸收贡献最大的均为Ni的铁锰氧化态。 相似文献
88.
As other calcsilicate-hosted ore deposits the Tumurtijn-ovoo Fe–Mn–Zn deposit is subdued to the question how the ore elements took place, whether linked to epigenetic silicification of a limestone host or bound to syngenetic precipitation during the deposition of a calcareous-siliceous sediment. The comparison of high Zn/Cd ratios of ores from Tumurtijn-ovoo ranging from 514 to 724 with those of other ore deposits relates Tumurtijn-ovoo to the group of submarine hydrothermal deposits which got their ore elements from basaltic source rocks by subseafloor leaching. Hence, respecting geological and textural features of the ores, a synsedimentary precipitation of zinc and cadmium in a volcano-sedimentary environment is suggested for Tumurtijn-ovoo. A group of low Zn/Cd ratios (274–297) is correlated with processes of mobilization and redeposition of sphalerite. 相似文献
89.
90.