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Timming of Lithospheric Extension in Northeastern China:Evidence from the Late Mesozoic Nianzishan A-Type Granitoid Complex

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Journal of Earth Science 2019年第4期30卷 689-706页

作者： Jinhua Qin Cui Liu yuchuan chen Jinfu Deng MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China

New zircon U-Pb dates obtained by laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS),whole-rock geochemical data and Sm-Nd and Rb-Sr isotopic data are presented for miarolitic alkaline granites,porphyritic syenite and rhyolites of the Nianzishan A-Type granitoid complex(NAGC)in the Great Xing'an Range-Songliao Basin in Northeast(NE)China.New crystallization ages of 112.95±0.93 and 114.1±1.71 Ma for granite and 118.6±0.51 Ma for porphyritic syenite were determined by high-precision LA-ICP-MS.The εNd(t)of the rocks range from +1.85 to+2.06,with Nd model ages(T(DM1))from 671 to 821 Ma,indicating that the NAGC originated from juvenile source rocks and exhibits geochemical characteristics of A1-and A-Type granite which formed in an extensional setting.We attribute the magmatism to regional extension and lithospheric thinning caused by the subduction of the western Pacific Plate about 120 to 100 Ma.

关键词： A-Type granitee new zircon UU-Pb zircon agees NE China lithospheric exxtension

Helium isotopic study on mantle degassing in the Altay orogenic zone,China

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Chinese Science Bulletin 1999年第11期44卷 1050-1053页

作者： Denghong Wang yuchuan chen Zhigang Xu Hongyang Li Tiande Li Chinese Acad Geol Sci Inst Mineral Deposits Beijing 100037 Peoples R China Chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China Xinjiang Inst Geol & Mineral Resources Urumqi Peoples R China

New helium isotopic data of ores and rocks from the Altay orogenic zone, Xinjiang,China are reported, which show that the pegmatites from No. 3 vein in the Keketuohai area have high 3He/4He ratios up to 1 .795 x 10-6 and 2.54 x 10-6. Such a result suggests that the metallogenic process of rare metal deposits in the Altay orogenic zone might be related to mantle degassing.

关键词： orogenic zone mantle degassing helium isotope.

Investigation on the cleaning of KDP ultra-precision surface polished with micro water dissolution machining principle

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Science China(Technological Sciences) 2017年第1期60卷 27-35页

作者： chen yuchuan GAO Hang WANG Xu GUO DongMing TENG XiaoJi Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education School of Mechanical Engineering Dalian University of Technology Dalian 116023 China

A potassium dihydrogen phosphate(KDP) optical crystal was machined to an ultra-precision surface with water-in-oil(W/O) micro emulsion polishing fluid. The micro water dissolution principle utilized in the machining process is discussed, its planarization mechanism is illustrated, and an ultra-precision polished surface with 2.205 nm RMS roughness is obtained. However, a substantial quantity of residual contamination remained on the polished surface after machining. This can seriously impact the optical performance of the crystal, and so it must be removed. Fourier transform infrared(FTIR) spectroscopy was used to conduct an investigation into the composition of the surface residue, and the results showed that the residue was comprised of organic chemicals with hydrocarbon chains and aromatic ether, i.e., mostly the polishing fluid. The cleaning method and the principle on which the KDP ultra precision surface investigation is based are discussed in detail, and the cleaning experiments with selected KDP-compatible organic solvents were then performed. FTIR transmittance spectra measurement and microscopic observations were employed to assess the effects of the cleaning process on the surface of the KDP crystal. The results showed that toluene cleaning achieved the most desirable results. This cleaning method produced a surface roughness of 1.826 nm RMS, which allows the KDP crystal to be applied to subsequent engineering applications.

关键词： KDP晶体清洗方法超精密抛光加工原理抛光表面水溶解傅里叶变换红外光谱表面粗糙度

On Minerogenetic Series: The Third Discussion

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 1-9页

作者： chen yuchuan PEI Rongfu WANG Denghong MNR Key Laboratory of Metallogeny and Mineral Assessment Chinese Academy of Geological SciencesBeijing 100037China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China

The minerogenetic(or metallogenetic) series of mineral deposits(called minerogenetic series for short) is an academic idea(concept) of studying minerogenetic characteristics in mineral deposit geology. It uses the views of systematology and mobilism to study mineralizing processes and naturally occurring mineral deposit assemblages formed in various stages of geological development in specific tectonic environments. The minerogenetic series is also a natural classification of mineral deposits. There are five hierarchical orders in the classification, with the minerogenetic series as the basic order and the core. The first order includes three categories: minerogenetic series association, minerogenetic series type, and minerogenetic series group. The second is the minerogenetic series, which is decomposed into three orders, i.e. the third, fourth, and fifth orders. The third is the minerogenetic subseries, the fourth is mineral deposit models(types), and the fifth is mineral deposits. Minerogenetic series is comparable to a certain extent metallogenic systems both in the research content and in their own research content. The study of minerogenetic series has both great theoretical significance and practical value for mineral prospecting. However, the study is still in its initial stage and a further study remains to be conducted.

关键词： concept of minerogenetic series order theoretic and practicable significance

The Ore-forming Mechanism of the Jiajika Pegmatite-Type Rare Metal Deposit in Western Sichuan Province:Evidence from Isotope Dating

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Acta Geologica Sinica(English Edition) 2013年第1期87卷 91-101页

作者： LI Jiankang WANG Denghong chen yuchuan MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResoucesCAGS Colleage of Earth Science and Resources Chang'an University

Granitic pegmatites are commonly thought to form by fractional crystallization or by liquid immiscibility of granitic magma; however, these proposals are based mainly on analyses of fluid and melt inclusions. Here, we use the Jiajika pegmatite deposit, the largest spodumene deposit in Asia, as a case study to investigate ore forming processes using isotope dating. Dating of a single granite sample from the Jiajika deposit using multiple methods gave a zircon U-Pb SHRIMP age of 208.4 ~ 3.9 Ma, an 4~Ar/39Ar age for muscovite of 182.9 ~ 1.7 Ma, and an 4~Ar/39Ar age for biotite of 169.9 ＋ 1.6 Ma. Based on these dating results and the 4~Ar/39Ar age of muscovite from the Jiajika pegmatite, a temperature-time cooling track for the Jiajika granite was constructed using closure temperatures of the different isotope systems. This track indicates that the granite cooled over ^-40 m. y., with segregation of the pegmatite fluid from the granitic magma at a temperature of ~700~C. This result suggests that the Jiajika pegmatite formed not by fractional crystallization, but by segregation of an immiscible liquid from the granitic magma. When compared with fractional crystallization, the relatively early timing of segregation of an immiscible liquid from a granitic magma can prevent the precipitation of ore-forming elements during crystallization, and suggests that liquid immiscibility could be an important ore-forming process for rare metal pegmatities. We also conclude that isotope dating is a method that can potentially be used to determine the dominant ore-forming processes that occurred during the formation of granite-related ore deposits, and suggest that this method can be employed to determine the formation history of the W-Sn ore deposits found elsewhere within the Nanling Metallogenic Belt.

关键词： isotope dating liquid immiscibility in granitic magmas pegmatite Jiajika rare metal deposit

Micro femoral head prosthesis in applications to collapsed femoral head necrosis in the weight-bearing dome(ARCO III):A case series with short-term follow-up

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Chinese Medical Journal 2024年第6期137卷 737-739页

作者： Zhongzheng Wang yuchuan Wang Tianyu Wang Yining Lu Xiaodong Lian Yanbin Zhu Wei chen Zhiyong Hou Yingze Zhang Department of Orthopaedic Surgery Hebei Medical University Third HospitalShijiazhuangHebei 050051China Key Laboratory of Biomechanics of Hebei Province ShijiazhuangHebei 050051China NHC Key Laboratory of Intelligent Orthopaedic Equipment ShijiazhuangHebei 050051China Chinese Academy of Engineering Beijing 100088China

Osteonecrosis of the femoral head(ONFH)is mainly caused by a decrease in the vascular supply to the subchondral bone of the femoral head,leading to the death of bone cells,degeneration and necrosis of the subchondral bone,and eventually collapse of the femoral head.^([1])Early and accurate diagnosis is the key to successful hip-preserving therapy,and the size/location of necrosis is the main determinant for ONFH treatment.Previous studies have shown that many hip-preserving therapies achieved satisfactory results in ONFH patients with Association Research Circulation Osseous(ARCO)I–II.When ONFH progresses to ARCO IV with clinical manifestations of osteoarthrosis,total hip arthroplasty(THA)may be the only option.

关键词： ARCO diagnosis death head

Time Sequence of Himalayan Endogenetic Mineralization on the East Side of the Qinghai-Tibet Plateau

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Acta Geologica Sinica(English Edition) 2000年第3期74卷 447-451页

作者： LUO Junlie chen yuchuan WANG Denghong Yunnan Bureau of Geology and Mineral Exploration and Development Kunming 650011Yunnan Chinese Academy of Geological Sciences(CAGS) Beijing 100037 3.Institute of Mineral ResourcesCAGSBeijing 100037

Among the endogenetic deposits in the Sanjiang area and at the west margin of the Yangtze platform, Himalayan deposits are the most important and contribute a large proportion of the resources of superlarge deposits. Among the controlled resources of this region, 84% of copper resources, 67% of Pb-Zn, 31% of Ag, 77% of gold and 24% of tin come from Himalayan deposits on the east side of the Qinghai-Tibet plateau. Himalayan endogenetic mineralization shows a relatively complete sequence evolution in the Sanjiang area and on the west margin of the Yangtze platform. Mineralization is manifested by gold deposits related to K-rich lamprophyre, REE deposits related to alkalic complexes and Cu-Au-polymetallic deposits related to alkaline porphyry. Six sequences of mineralization evolution since 65 Ma B.P. in the Sanjiang area and on the west side of the Yangtze platform can be recognized. Himalayan endogenetic mineralization on the east side of the Qinghai-Tibet plateau reached its peak before the Oligocene, corresponding to episodes I and II of the intracontinental orogenic cycle. Afterwards, mineralization waned obviously.

关键词： time sequence Himalayan endogenetic deposits Qinghai-Tibet plateau

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基于美标的某海外散货仓库大跨钢结构选型

港口航道与近海工程 2024年第2期61卷 15-18页

作者：丁志全陈豫川孙秀丽李彪王乐鹏潘长卿张立平中交第四航务工程勘察设计院有限公司广东广州510290 中国港湾工程有限责任公司北京100027 广东财经大学广东广州510230

随着近年来“一带一路”持续推进,大跨钢结构在海外应用越来越广泛,如何在海外工程背景下采用美标进行钢结构选型成为了行业难点。本文基于某海外散货仓库项目,介绍了美标设计的主要结构分析过程,并给出了在全生命周期经济性下的结构选... 详细信息

随着近年来“一带一路”持续推进,大跨钢结构在海外应用越来越广泛,如何在海外工程背景下采用美标进行钢结构选型成为了行业难点。本文基于某海外散货仓库项目,介绍了美标设计的主要结构分析过程,并给出了在全生命周期经济性下的结构选型。通过结构比选提出了一种新型自稳型门式钢架结构体系,其具有较好的经济性和极大的增加了仓库使用空间,为类似项目提供了参考。

关键词：散货仓库结构选型成本分析门式钢架

Characteristics of Ore-forming Fluid of the Gaoshan Gold-Silver Deposit in the Longquan Area, Zhejiang Province and its Implications for the Ore Genesis

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1321-1340页

作者： JIANG Biao WANG chenghui chen yuchuan WU Baogui LIAO Peng chen Zhengle HAN Fengbin MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Chinese Academy of Geological Sciences Beijing 100037China No.7 Geological Team of Zhejiang Province LishuiZhejiang 323000 Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081

The Gaoshan gold-silver deposit, located between the Yuyao-Lishui Fault and Jiangshan- Shaoxing fault in Longquan Area, occurs in the Suichang-Longquan gold-silver polymetallic metallogenic belt. This study conducted an investigation for ore-forming fluids using microthermometry, D-O isotope and trace element. The results show that two types of fluid inclusions involved into the formation of the deposit are pure liquid phase and gas-liquid phase aqueous inclusions. The homogenization temperature and salinity of major mineralization phase ranges from 156~C to 236~C （average 200~C） and 0.35% to 8.68% （NaCleqv）（average 3.68%）, respectively, indicating that the ore-forming fluid is characteristic of low temperature and low salinity. The ore- forming pressure ranges between in 118.02 to 232.13＂105 pa, and it is estabmiated that the ore- forming depth ranges from 0.39 to 0.77 km, indicating it is a hypabyssal deposit in genesis. The low rare earth elements content in pyrites, widely developed fluorite in late ore-forming stage and lack of chlorargyrite （AgCI）, indicates that the ore-forming fluid is rich in F rather than CI. The ratios of Y/ Ho, Zr/Hf and Nb/Ta of between different samples have little difference, indicating that the later hydrothermal activities had no effects on the former hydrothermal fluid. The chondrite-normalized REE patterns of pyrites from country rocks and ore veins are basically identical, with the characteristics of light REE enrichment and negative Eu anomalies, implying that the ore-forming fluid was oxidative and derived partly from the country rocks. The JD and jlSo of fluid inclusions in quartz formed during the main metallogenic stage range from -105%o to -69 %0 and -6.01%o to -3.81%o, respectively. The D-O isotopic diagram shows that the metallogenic fluid is characterized by the mixing of formation water and meteoric water, without involvement of magmatic water. The geological and geochemical characteristics of the Gaoshan gold-silver deposit are similar to those of continental volca

关键词： ore-forming fluid trace elements D-O isotope ore genesis Gaoshan glod-silver deposit