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GEOCHEMICAL CHARACTERISTICS OF PLATINUM GROUP ELEMENTS IN JINCHUAN SUPER-LARGE SULFIDE COPPER-NICKEL DEPOSIT, JINCHANG CITY, gansu PROVINCE, CHINA

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Geotectonica et Metallogenia 2005年第2期29卷 152-163页

作者： WANG Ruiting MAO Jingwen HE Ying WANG Dongsheng tang zhongli Faculty of Geosciences and resources China University of Geosciences Beoing 100083China bureau of Geological Exploration for Nonferrous Metals in Northwest China Xi＇an SX710054 China Institute of mineral resources Chinese Academy of Geological SciencesBeifing 100037 China Department of geology Northwest University Xi＇an SX 710069 China Faculty of Geosciences and resources Chang＇an University Xi＇an SX 710054 China

The platinum-group element geochemistry of rocks and ores from Jinchuan super-large copper-nickel sulfide deposit is systemically studied in this paper. The Cu/Pd mean ratio of Jinchuan intrusion is lower than that of original mantle magma, which indicates that these ultrabasic rocks were crystallized from magma that lost Pd in the form of melting segregation of sulfides. The PGE of the rocks show trend of partial melting, similar to that of mantle peridotite, which shows that magma formation occurs during rock-forming and ore-forming processes. The chondrite normalized PGE patterns of the rocks and ores are well related to each other, which signifies the signatures of multi-episode magmatic intrusion, melting and differentiation in the formation processes of rocks and ores. In addition, analyses about the relation between PGE and S, and study on Re-Os isotopes indicate that few contamination of the crustal substances occurred during the magmatic intrusion and the formation of deposit. However, contamination by crustal substances helps to supply part of the S for the enrichment of PGE. Meanwhile, the hydrothermal process is also advantageous for the enrichment of PGE, especially lbr Pt and Pd, due to deep melting segregation. The characteristic parameters （such as Pt/（Pt＋Pd）, （Pt＋Pd）/（Ru＋Ir＋Os）, Pd/Ir, Cu/（Ni＋Cu）, and so on.） for platinum-group elements for Jinchuan sulfide copper-nickel deposit show the same features as those for sulfide copper-nickel deposit related to basic magma, which also illustrates its original magma property representative of Mg-high tholeiite. Therefore, it is the marie （not ultramafic） magma that resulted in the formation of the superlarge sulfide copper-nickel deposit enriched in Cu and PGE. To sum up, the geochemical characteristics of platinum-group elements in rocks and ores from Jinchuan copper-nickel sulfide deposit are constrained by the continental rift tectonic environment, the parent magma features, the enriched mantel magma so

关键词： platinum group elements copper-nickel sulfide deposit geochemical feature Jinchuan

基于三维地质模型的路桥工程特殊地质岩体勘察方法研究

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中国高新科技 2024年第7期 39-41页

作者：唐小东甘肃中科华建规划设计发展有限公司甘肃兰州730030

路桥工程施工前对其地质条件尤其是特殊地质岩体进行勘察具有积极意义,甚至影响未来的工程设计与施工。由于特殊地质岩体的复杂性和不确定性,传统勘察方式存在效率较低、精度不高、人为影响较大等弊端难以准确掌握其性质和特征。因此,... 详细信息

路桥工程施工前对其地质条件尤其是特殊地质岩体进行勘察具有积极意义,甚至影响未来的工程设计与施工。由于特殊地质岩体的复杂性和不确定性,传统勘察方式存在效率较低、精度不高、人为影响较大等弊端难以准确掌握其性质和特征。因此,需要研究新的勘察方法。基于此,文章重点针对3种三维地质模型在路桥工程中的特殊地质岩体勘察方法进行介绍,旨在为后续实践工作提供指导。

关键词：三维地质模型路桥特殊地质岩体勘察

Oligocene-Miocene magnetostratigraphy and magnetic anisotropy of the Baxbulak section from the Pamir-Tian Shan convergence zone

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Oligocene-Miocene magnetostratigraphy and magnetic anisotrop...

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Zihua tang Xinxin Dong Xu Wang zhongli Ding Key Laboratory of Cenozoic geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences

As the northernmost part of the Indo-Eurasian collision belt, the Pamir-Tian Shan convergence zone(PTCZ) is a strategic location for understanding intracontinental deformation. Here we present a magnetostratigraphic investigation of a continuous section from the Baxbulak region, to better constrain regional tectonic history. Rock magnetic analyses indicate that hematite and magnetite are the main carriers of characteristic remanent magnetization. The resulting polarity sequence allows a distinct correlation to the geomagnetic polarity time scale, showing that the section spans the interval of 29.1–20.7 Ma. Rock magnetic results further suggest that paramagnetic and antiferromagnetic minerals dominantly contribute to anisotropy of magnetic susceptibility(AMS) of the sequence. Thus, the AMS would indicate the preferred orientations of the mineral grains that are sensitive to tectonic strain. At around 26 Ma, the grouped principal minimum perpendicular to the bedding diverts to a girdle distribution in a N-S direction, demonstrating the overprint of tectonic fabric to previous weakly deformed sedimentary fabric. This would be interpreted as a marked increase in tectonic strain, consistent with various evidence from the Pamir and the neighboring basin that show the Pamir began to migrate northward. Moreover, the coincident changes in distribution of AMS principal axes, in both direction and magnitude, are comparable to the regional counterclockwise rotations observed from paleomagnetic data, likely related to orogenesis.

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探讨如何提高地质矿产勘查及找矿技术

世界有色金属 2024年第4期 108-110页

作者：李堂积甘肃省地质矿产勘查开发局第三地质矿产勘查院甘肃兰州730050

地质矿产勘查和找矿技术是矿产资源开发的重要环节,对于保障国家经济安全和推动经济发展具有重要意义。但是随着矿产资源的不断开发和利用,地质矿产勘查及找矿的难度越来越大,需要不断提高技术的水平和效率。基于此,本文分析提高地质矿... 详细信息

地质矿产勘查和找矿技术是矿产资源开发的重要环节,对于保障国家经济安全和推动经济发展具有重要意义。但是随着矿产资源的不断开发和利用,地质矿产勘查及找矿的难度越来越大,需要不断提高技术的水平和效率。基于此,本文分析提高地质矿产勘查及找矿技术的效率和精度的有效措施,供广大相关从业人员参考。

关键词：地质矿产勘查找矿工作技术创新资源利用

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A～6 Ma chemical weathering history,the grain size dependence of chemical weathering intensity,and its implications for provenance change of the Chinese loess-red clay deposit

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A～6 Ma chemical weathering history,the grain size dependenc...

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Shangfa Xiong~*,zhongli Ding,Yuanjian Zhu,Ru Zhou,Haijian Lu Key Laboratory of Cenozoic geology and Environment,Institute of geology & Geophysics,Chinese Academy of Sciences,100029 Beijing,China

Major element chemical analyses of the Baishui loess—red clay sequence(35°24’ 10"N,106°54’ 43"E, gansu Province,China) reveal that,the chemical weathering intensities inferred from CIA(chemical index of alteration) values have progressively weakened and increased in amplitude with decreasing age. The general trend of the CIA can be correlated well with the oxygen isotope variations of the deep sea *** of multiple size fractions(<5μm,5—20μm and 20—63μm) indicate that the CIA and the major element abundances are strongly grain size *** chemical alternation of all three size fractions is relatively weak,and the long-term variation in chemical composition of the loess—red clay is mainly controlled by the mixing of fresh detritus from different source *** CIA variability of the coarse fractions(5—20μm and 20—63μm) within the section is apparently different from that of the fine fraction(<5μm),implying a different erosion—transportation—deposition—weathering *** 1 Ma onward,CIA values for all size fractions decrease,indicating an increasing input of fresh or poorly weathered detritus in the desert source regions of loess *** variations in the KO/AlO, NaO/AlO,CaO/AlO and MgO/AlO ratios from 4.5 Ma to about 0.6 Ma in bulk and size fractioned samples may reflect provenance change as well as changing chemical weathering processes.

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Negativeδ18O-δ13C relationship of pedogenic carbonate from northern China indicates a strong response of C3/C4 biomass to the seasonality of Asian monsoon precipitation

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Negativeδ18O-δ13C relationship of pedogenic carbonate from...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Shiling Yang zhongli Ding Xu Wang Zihua tang Zhaoyan Gu Key Laboratory of Cenozoic geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences

Evaluating how future climate changes may impact C/C biomass in East Asia depends largely on the understanding of the relationship between past C/C variations and Asian monsoon *** glacial-interglacial variations in C/C biomass have been readily ascribed to the summer ***,the internal processes governing the link of C/C vegetation to the Asian monsoon have not been clearly *** we present isotopic results of pedogenic carbonate from northern China for the *** last and penultimate interglacial *** of the observed and predictedδO values of modern soil carbonate from gravelly soils suggests that pedogenic carbonate forms mainly in warm,rainy *** nodules from the Chinese loess demonstrate a distinct negativeδO-δC relationship and a wider scatter of isotopic values in the southern Loess Plateau than in the northern *** combining rainfall,δO of precipitation and the peak of C and C plant metabolism,we develop a conceptual model to explain the isotopic signatures of the carbonate *** model shows that a narrowly-focused season of monsoon precipitation at a specific site produces lowδO values of soil water and simultaneously favors C over C *** model further suggests that the scattered isotopic values of soil carbonate reflect a strong summer monsoon while the focused values indicate a weak summer monsoon.δC values of soil carbonate indicate a striking pattern of northward-increasing C vegetation for the last interglacial,while a flat spatial pattern is seen for the penultimate interglacial and the *** is inferred that the summer monsoon was stronger during the last interglacial than during the penultimate interglacial and the Holocene,leading to a northward displacement of C forest ecosystems into the southern Loess *** addition,an in-phase relationship between intra-noduleδC andδO values suggests a strong and possibly rapid response of C/C biomass to the seasonality of

关键词： Chinese loess Pedogenic carbonate East-Asian summer monsoon Stable isotopes C3/C4 vegetation Precipitation seasonality

Anisotropy of magnetic susceptibility of the Jingou River section:Implications for late Cenozoic uplift of the Tian Shan

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Anisotropy of magnetic susceptibility of the Jingou River se...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Zihua tang Baochun Huang Xinxin Dong Junliang Ji zhongli Ding Key Laboratory of Cenozoic geology and Environment Institute of geology and Geophysics Chinese Academy of Sciences MOE Key Laboratory of Western China's Environmental System Lanzhou University State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Key Laboratory of Cenozoic geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences Key Laboratory of Biogeology and Environmental geology of Ministry of Education China University of Geosciences

Better constraints on the uplift history of Tian Shan will increase our understanding of both mountain building processes and deformation patterns related to the India-Asian *** of magnetic susceptibility(AMS) holds great potential to track variations in tectonic strain,which is ultimately responsible for mountain *** we present an AMS record,spanning the interval of 28-4 Ma,from the fluviolucastrine Jingou River section in the Tian Shan *** magnetic measurements show that the AMS are dominated by antiferromagnetic hematite and some paramagnetic minerals,both of which have a crystallographic preferred orientation,and therefore the AMS sequence may be applied to reconstruct tectonic *** the principal minimum(K) direction is nearly perpendicular to the bedding plane, indicative of a predominantly sedimentary fabric for the section,the tightly grouped principal maximum (K) parallel to the fold axis suggests that the section was subject to an embryonic deformation at least since the Late *** K direction is most likely associated with the N-S strain caused by the India-Asian *** the intervals of 23.3-20.0 Ma and 16.5-14.0 Ma,the strain markedly increased as evidenced by more tightly grouped K directions and K largely distributed within a clear N-S *** two intervals are accompanied by changes in sedimentary facies(higher energy conditions and doubled sedimentation rates),and are interpreted as the periods when the Tian Shan experienced significant uplift.A conceptual model is tentatively proposed to reconcile various timings for the Tian Shan uplift.

关键词： Tian Shan anisotropy of magnetic susceptibility magnetic fabrics rock magnetism tectonic uplift

Early Eocene carbon isotope excursions: Evidence from the terrestrial coal seam in the Fushun Basin,Northeast China

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Early Eocene carbon isotope excursions: Evidence from the te...

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Zuoling Chen zhongli Ding Zihua tang Xu Wang Shiling Yang Key Laboratory of Cenozoic geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

A series of transient global warming events between 56 and 50 Ma are characterized by a pronounced negative carbon isotope excursion(CIE). However, the documents of these hyperthermals,such as Eocene Thermal Maximum 2 and H2 events, have come chiefly from marine sediments, and their expression in terrestrial organic carbon is still poorly constrained. Here we yield a high-resolution carbon isotope record of terrestrial organic material from the Fushun Basin, which displays four prominent CIEs with magnitudes larger than 2.5‰. Based on age constraint and comparisons with deep-sea records, our data provide the first evidence of the four hyperthermals in coal seams and suggest a global significance of these events. Moreover, the difference of CIE magnitudes between marine and terrestrial records shows a significant linear correlation with the marine carbonate CIE, implying that these events are likely attributable to recurring injections of 13C-depleted carbon from submarine methane hydrates and/or permafrost.

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鄂尔多斯盆地西南缘中下侏罗统地层物源及构造演化对铀成矿的制约

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地球科学 2024年第5期49卷 1793-1809页

作者：俞礽安李彤杨桐旭赵华雷涂家润胡永兴唐永香中国地质科学院矿产资源研究所北京100037 中国地质调查局天津地质调查中心天津300170 中国地质调查局铀矿地质重点实验室天津300170 甘肃省地质调查院甘肃兰州730000 天津地热勘查开发设计院天津300250

鄂尔多斯盆地西南缘位于阿拉善地块、秦岭造山带与祁连造山带3个构造单元的交汇部位,给含铀岩系地层的物源体系和铀成矿作用研究带来一定困难.通过选取泾川研究区的直罗组和延安组砂岩进行碎屑锆石U-Pb测年和微量元素研究,分析结果显示... 详细信息

鄂尔多斯盆地西南缘位于阿拉善地块、秦岭造山带与祁连造山带3个构造单元的交汇部位,给含铀岩系地层的物源体系和铀成矿作用研究带来一定困难.通过选取泾川研究区的直罗组和延安组砂岩进行碎屑锆石U-Pb测年和微量元素研究,分析结果显示:泾川地区直罗组砂岩的碎屑锆石年龄呈215~767Ma和1501~1905Ma;延安组砂岩的碎屑锆石年龄呈215~453Ma、1506~1918Ma和2136~2579Ma.与源区同位素年代学对比认为直罗组和延安组砂岩的物源成分较为复杂,主要来自于阿拉善地块,其次来自于华北板块北缘和北祁连地区.从延安组到直罗组沉积期,祁连山和阿拉善陆块发生了快速隆升和剥蚀,为直罗组提供了物源,并且古生代和中生代侵入岩体提供物源的占比逐渐增大.研究西部靠近盆缘地区以中侏罗统砂岩层为找矿目的层,靠近盆内含矿层位逐渐变年轻.

关键词：鄂尔多斯盆地泾川中下侏罗统碎屑锆石U-Pb年龄物源矿床构造地质