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Journal of Earth Science 2014年第2期25卷 224-240页

作者： Mengjing Xu Cai Li Wei Xu Chaoming Xie Peiyuan hu Ming Wang College of Earth Science Jilin University

In order to investigate the evolution of Shiquanhe-Yongzhu-Jiali ophiolitic melange belt, the gabbros from new discovered Zhongcang ophiolitic melange are studied through petrology, whole-rock geochemistry, zircon U-Pb dating and Lu-Hf isotope. The gabbros investigated in this paper contain cumulate gabbro and gabbro dike, and they have undergone greenschist-amphibolite facies metamorphism. The chondrite normalized rare earth element （REE） patterns of most of these rocks show flat types with slightly light REE （LREE） depletion and the N-MORB normalized incompatible elements diagrams indicate depletion in high field strength elements （HFSE）（Nb, Ta） and enrichment in large ion lithophile elements （lile）. These gabbros have island arc and mid-ocean ridge basalt af- finities, suggesting that they were originated in an oceanic back arc basin. Whole rock geochemistry and high positive εNd（t） values show that these gabbros were derived from -30% partial melting of a spinel lherzolite mantle, which was enriched by interaction with slab-derived fluids and melts from sediment. U-Pb analyses of zircons from cumulate gabbro yield a weighted mean age of 114.3±1.4 Ma. Based on our data and previous studies, we propose that an intra-oceanic subduction system and back arc basin operated in the Neo-Tethy Ocean of central Tibet during Middle Jurassic and Early Creta- ceous, resembling modern active intra-oceanic subduction systems in the western Pacific.

关键词： Tibet Zhongcang ophiolitic melange gabbro Shiquanhe-Yongzhu-Jiali ophiolitic me- lange belt geochemistry.

Geochemical Characteristics and Geological Significance of Early Permian Baya'ertuhushuo Gabbro in South Great Xing'an Range

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Acta Geologica Sinica(English Edition) 2011年第1期85卷 116-129页

作者： LIU Jianfeng CHI Xiaoguo ZHAO Zhi ZHANG Xingzhou MA Zhihong WANG Tiefu hu Zhaochu College of Earth Sciences Jilin University Changchun 130061 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China The Center of Test and Science Experiment Jilin University Changchun 130026 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China

Field geological investigation and geochemical analysis are carried out on Baya＇ertuhushuo Gabbro in South Great Xing＇an Range. Field investigation reveals that the gabbro is a magmatic intrusion rather than a component of an ophiolite suite as previously thought. Zircon laser ablation inductively coupled plasma mass spectroscopy （LA-ICP-MS） U-Pb dating indicates the gabbro was formed in 274-275 Ma, just as the widespread volcanic rocks of Dashizhai Formation （P1d）, monzogranites and miarolitic alkali-feldspar granites in the study area. The gabbro has SiO2 content between 47.23 wt% and 50.17 wt%, high MgO and FeOT contents of 6.95-11.29 wt% and 7.32- 12.24wt%, respectively, and it belongs to low-K tholeiitic series in the SiO2-K2O diagram. The Chondrite-normalized rare earth element （REE） patterns and primitive mantle-normalized spider diagrams of the gabbro are similar to those of Normal Mid-Ocean Ridge Basalt （N-MORB） except for the enrichment of large ion lithophfle elements （lile）, such as Rb, Ba and K. In trace element tectonic discriminative diagrams, the samples are mainly plotted in the N-MORB field, and Zircon in situ Lu-Hf isotopic analysis also indicates the gabbro originated from depleted mantle. Through synthetic studies of the geochemical characteristics and petrogenesis of Baya＇ertuhushuo gabbro, volcanic rocks of Dashizhai Formation and granitoids in the area, it is suggested that the early Permian magmatism in the Xilinhot-Xiwuqi area formed in the tectonic setting of asthenosphere upwelling, which was caused by breaking-off of the subducted Paleo-Asian Ocean slab.

关键词： gabbro geochemistry early Permian zircon U-Pb age south Great Xing'an Range

Jurassic Intra-plate Basaltic Magmatism in Southeast China:Evidence from Geological and Geochemical Characteristics of the Chebu Gabbroite in Southern Jiangxi Province

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Acta Geologica Sinica(English Edition) 2005年第5期79卷 662-672页

作者： XIE Guiqing MAO Jingwen hu Ruizhong LI Ruiling JIANG Guohao CAO Jinjian ZHAO Junhong State Key Laboratory of Geological Process and Mineral Resourses China University of Geosciences Beijing 100083 Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou 550002 Earth Science Department Sun Yat-Sun University Guangzhou Guangdong 510275 Earth Science Department Sun Yat-Sun University Guangzhou Guangdong 510275

Geochemical and isotopic investigations have been carded out on the Chebu gabbroite in southern Jiangxi Province, southeast China and these results are compared with gabbro bodies along the coast of Fujian Province in order to understand their magma sources and tectonic implications. The Chebu intrusion formed at the beginning of the Middle Jurassic （172~4.3 Ma）. These rocks are Ti-rich and Al-poor in major elements, characterized by strong enrichment in large-ion lithophile elements （lile） and moderate enrichment in high field strength elements （HFSE） and light rare-earth elements CLREE）, without pronounced Nb or Ta anomalies. Age-correlated Sr-Nd isotope ratios show moderately high ranges of （^87Sr/^86Sr）i from 0.7065 to 0.7086 and 0.5124 to 0.5125 of （^143Nd/^144Nd）i. The geochemical characteristics of the Chebu gabbroite suggest that it is notably different from island-arc basalt and similar to intra-plate basaltic rocks. By combining interpretations of its geological and geochemical characteristics and the regional geological development history, the Chebu gabbroitic intrusion is thought to be the product of asthenosphere upwelling and rapid lithosphere extension during a transition of tectonic systems in southeast China. The tectonic environment and source characteristics of the intrusion are different from Cretaceous gabbro bodies along the coast of Fujian Province, The former formed in a tectonic environment of rapid intra-plate lithospheric extension and the source characteristics were of a weakly enriched primitive mantle, whereas the latter originated mainly in a volcanic-magmatic arc extensional tectonic environment and the nature of the source was an enriched mantle with more subduct subducted components.

关键词： gabbroite geochemical characteristics geodynamics setting Jurassic Jiangxi southeast China

Neoproterozoic I-type granites in the Central Tianshan Block (NW China):geochronology,geochemistry,and tectonic implications

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Journal of Arid Land 2022年第1期14卷 82-101页

作者： SONG Yujia LIU Xijun XIAO Wenjiao ZHANG Zhiguo LIU Pengde XIAO Yao LI Rui WANG Baohua LIU Lei hu Rongguo Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration College of Earth SciencesGuilin University of TechnologyGuilin 541004China Xinjiang Research Center for Mineral Resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resource Guilin University of TechnologyGuilin 541004China

The Central Tianshan Block is one of numerous microcontinental blocks within the Central Asian Orogenic Belt(CAOB)that overlies Precambrian basement *** the evolution of these ancient basement rocks is central to understanding the accretionary and collisional tectonics of the CAOB,and their place within the Rodinia ***,to date,the timing and tectonic settings in which the basement rocks in the Central Tianshan Block formed are poorly constrained,with only sparse geochemical and geochronological data from granitic rocks within the northern segment of the ***,we present a systematic study combining U-Pb geochronology,whole-rock geochemistry,and the Sr-Nd isotopic compositions of newly-identified granitic gneisses from the Bingdaban area of Central Tianshan *** analyzed samples yield a weighted mean Neoproterozoic 206Pb/238U ages of 975-911 *** weakly-peraluminous granitic rocks show a common geochemical I-type granite *** granitic gneisses are calc-alkaline and enriched in large ion lithophile elements(liles)and light rare earth elements(LREEs),but they are depleted in high field strength elements(HFSEs);these characteristics are similar to those of typical subduction-related *** samples show initial(^(87)Sr/^(86)Sr)(t)ratios between 0.705136 and *** forεNd(t)in the granitic gneisses are in the range from-5.7 to-1.2,which correspond to Nd model ages of 2.0-1.7 Ga,indicating a role for Mesoproterozoic to Paleoproterozoic rocks in the generation of the granitic *** documented geochemical features indicate that the protoliths for the gneisses have a similar petrogenesis and magmatic source,which may reflect partial melting of thickened crust with the addition of small amounts of mantle-derived *** Central Tianshan Block probably constitute part of an exterior orogen that developed along the margin of the Rodinian supercontinent during the Early Neoproterozoic and underw

关键词： Neoproterozoic I-type granites geochronology Central Tianshan Block Rodinian supercontinent Central Asian Orogenic Belt(CAOB)

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PACU交接核查单的制订及应用效果分析

麻醉安全与质控 2021年第6期5卷 423-426页

作者：陈庆红盛丽乐胡少飞兰星华中科技大学同济医学院附属协和医院麻醉科湖北武汉430022

目的探讨麻醉恢复室(PACU)交接核查单在PACU麻醉护士交接班中的应用效果。方法选取我院2021年6~8月PACU收治的200例患者,采用随机分组法分为对照组(A组,n=100)和试验组(B组,n=100)。A组采用PACU交接核查单进行纸质交接班,B组采用传统的... 详细信息

目的探讨麻醉恢复室(PACU)交接核查单在PACU麻醉护士交接班中的应用效果。方法选取我院2021年6~8月PACU收治的200例患者,采用随机分组法分为对照组(A组,n=100)和试验组(B组,n=100)。A组采用PACU交接核查单进行纸质交接班,B组采用传统的口头交接班,比较2组种交接班方式的交接时间和交接遗漏情况。结果B组患者交接班时间较A组明显缩短;病情交接不完整、物品遗漏、交接内容与记录单不一致发生率明显低于A组(P<0.05)。结论应用PACU交接核查单,可减少交接环节的失误和差错,提高麻醉护士交接班质量,保障患者安全。

关键词：麻醉恢复室交接核查麻醉护士患者安全

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湘中锡矿山中生代煌斑岩及其成因研究

岩石学报 2016年第7期32卷 2041-2056页

作者：胡阿香彭建堂有色金属成矿预测教育部重点实验室中南大学地球科学与信息物理学院长沙410083 矿床地球化学国家重点实验室中国科学院地球化学研究所贵阳550002

湘中锡矿山锑矿是世界上最大的锑矿床,被誉为"世界锑都",矿区东部出露的煌斑岩是该区唯一的岩浆活动。本次利用岩石学、矿物学和地球化学方法,对该煌斑岩的岩相学及主量元素、微量元素和Sr-Nd同位素进行了系统研究,并探讨了其源区属性... 详细信息

湘中锡矿山锑矿是世界上最大的锑矿床,被誉为"世界锑都",矿区东部出露的煌斑岩是该区唯一的岩浆活动。本次利用岩石学、矿物学和地球化学方法,对该煌斑岩的岩相学及主量元素、微量元素和Sr-Nd同位素进行了系统研究,并探讨了其源区属性、形成机制、形成的构造环境以及煌斑岩与成矿的关系。研究表明,该区煌斑岩为典型的钙碱性煌斑岩,其岩石地球化学表现出富Ti O_2、贫Al_2O_3和Mg O,富集lile和LREE,亏损HFSE,高(^(87)Sr/^(86)Sr)i、低ε_(Nd)(t)值的特征,与EM2型富集地幔相似。在锡矿山煌斑岩形成过程中,地壳混染作用十分有限。岩浆上升至地表的过程中经历了橄榄石+斜长石的结晶分异作用。锡矿山煌斑岩形成过程为:在石榴石稳定场条件下含金云母相的二辉橄榄岩地幔发生部分熔融,形成初始源区,洋壳沉积物通过俯冲作用形成的流体交代初始源区,岩浆快速上升至地表形成煌斑岩。锡矿山煌斑岩与该区锑矿没有成因联系。

关键词：地球化学源区性质煌斑岩锡矿山湘中

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乌井水库坝顶纵向裂缝变形监测与分析

江西水利科技 2021年第3期47卷 229-234页

作者：王乐芹胡松涛章李乐林太清戴国强海洋石油工程股份有限公司天津300451 江西省水利科学院江西南昌330029 南昌市水利规划设计院江西南昌330009

设有混凝土防渗墙的土石坝出现坝顶纵向裂缝是常见的一种安全隐患,坝顶纵向裂缝的出现和扩展增加了大坝安全风险.本文在详细调查乌井水库纵向裂缝分布情况的基础上,经过一年运行周期的裂缝观测与变形观测,分析获得了纵向裂缝开度随库水... 详细信息

设有混凝土防渗墙的土石坝出现坝顶纵向裂缝是常见的一种安全隐患,坝顶纵向裂缝的出现和扩展增加了大坝安全风险.本文在详细调查乌井水库纵向裂缝分布情况的基础上,经过一年运行周期的裂缝观测与变形观测,分析获得了纵向裂缝开度随库水位变化的扩展规律.进一步采用变形倾度法分析了大坝表面变形与坝顶纵向裂缝的相关性,结果表明:坝顶纵向裂缝的开度变化规律基本与变形倾度的增量变化一致,裂缝随变形倾度增量的减小而闭合,随变形倾度增量的增加而张开.

关键词：坝顶纵向裂缝监测变形倾度法分析乌井水库

新疆谢米斯台地区晚古生代俯冲作用:来自塞勒肯特岩体的岩石学、年代学及地球化学证据

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岩石学报 2021年第4期37卷 1139-1158页

作者：张望王居里胡洋大陆动力学国家重点实验室西北大学地质学系西安710069 商洛西北有色七一三总队有限公司商洛726000

塞勒肯特岩体出露于谢米斯台中东部,岩性主要为二长花岗岩、石英闪长岩及花岗闪长岩。本文通过锆石U-Pb年代学、岩石地球化学和Sr-Nd-Hf同位素等研究,探讨其形成的构造环境及岩石成因。结果表明,二长花岗岩(400.9±4.3Ma)和石英闪长岩(3... 详细信息

塞勒肯特岩体出露于谢米斯台中东部,岩性主要为二长花岗岩、石英闪长岩及花岗闪长岩。本文通过锆石U-Pb年代学、岩石地球化学和Sr-Nd-Hf同位素等研究,探讨其形成的构造环境及岩石成因。结果表明,二长花岗岩(400.9±4.3Ma)和石英闪长岩(398.1±4.5Ma)形成于早泥盆世,花岗闪长岩(381.7±2.9Ma)形成于晚泥盆世。岩体整体富碱,属于准铝质-弱过铝质高钾钙碱性花岗岩类。轻重稀土分馏较明显且富集轻稀土((La/Yb)_(N)=5.09~9.22),Eu异常不明显,相对富集Rb、Th、U、K等元素,亏损Nb、Ta、Ti等高场强元素;二长花岗岩和石英闪长岩具有低的(^(87)Sr/^(86)Sr)_(i)值(0.7040~0.7043),正ε_(Nd)(t)值(+4.85~+6.18),年轻的t_(DM1)(Nd)年龄(663~732Ma),二长花岗岩锆石εHf(t)值为+7.94~+12.12,t_(DM2)(Hf)=648~889Ma;花岗闪长岩也具有低的(^(87)Sr/^(86)Sr)_(i)值(0.7045~0.7046),正ε_(Nd)(t)值(+4.61~+4.80),年轻的t_(DM1)(Nd)年龄(731~749Ma),花岗闪长岩锆石ε_(Hf)(t)值为+4.26~+11.69,t_(DM2)(Hf)=631~1103Ma。综合研究表明,塞勒肯特岩体形成于俯冲背景下的大陆边缘弧环境,可能是俯冲板片脱水交代地幔楔产生的玄武质岩浆上涌,导致新生下地壳发生部分熔融。二长花岗岩及石英闪长岩均来源于新生下地壳的部分熔融;花岗闪长岩主要来源于新生下地壳的部分熔融,并有少量幔源物质的加入,花岗闪长岩中的暗色微粒包体可能是幔源物质与新生下地壳部分熔融的岩浆未发生完全混合,最终冷凝结晶的产物。谢米斯台地区与俯冲相关的中酸性岩浆活动至少从晚奥陶世一直延续至晚泥盆世。

关键词：年代学地球化学俯冲作用陆缘弧新疆谢米斯台

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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： Ya-Chun Cai Hong-Rui Fan M.Santosh Fang-Fang hu Kui-Feng Yang Zhaochu hu Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of Sciences School of Earth Sciences and Resources China University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

The widespread mafic to intermediate dykes in the northern Sulu orogen provide important constrains on mantle source characteristics and geodynamic *** we present LA-ICPMS zircon U–Pb ages which indicate that the dykes were emplaced during Early Cretaceous(13–108 Ma).The rocks show Si O in the range of 46.2 to59.5 wt.% and alkalic and shoshonitic affinity with high concentrations of Mg O(up to 7.6 wt.%),Cr(up to422 ppm) and Ni(up to 307 ppm).They are enriched in light rare earth elements LREE(La,Ce,Pr,Nd,Sm and Eu) and large ion lithophile elements(lile,Rb,Sr,Ba,U and Th) and show strong depletion in high field strength elements(HFSE,Nb,Ta,Ti and P).The dykes possess uniformly high(Sr/Sr)i(0.70824–0.70983),low εNd(t)(-14.0 to-17.4) and(Pb/Pb)i(16.66–17.02) and negative εHf(t)(-23.5 to-13.7).Our results suggest that the source magma did not undergo any significant crustal contamination during *** systematic variation trends between Mg O and major and trace elements suggest fractionation of olivine and *** highly enriched mantle source for these rocks might have involved melts derived from the subducted lower crust of Yangtze Craton that metasomatized the ancient lithospheric mantle of the North China Craton.

关键词： Mafic to intermediate dykes Subduction-related metasomatism Lithospheric mantle Petrogenesis Northern Sulu orogen

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水利工程施工质量监理专项检测探讨

江西水利科技 2022年第6期48卷 457-461页

作者：李平福胡松涛章李乐戴国强陈良捷江西省九江市共青城市农业农村水利局江西共青城332020 江西省水利科学院江西南昌330029 南昌市水利规划设计院江西南昌330009 江西省水工安全工程技术研究中心江西南昌330029

现行《水利工程施工监理规范》(SL288-2014)在条文说明中首次引用了专项检测的概念,规定了专项检测实施内容,但未对专项检测进行定义,也未制定专项检测的项目、频率及程序,因此专项检测在水利工程中实施效果并不十分理想。本文从专项检... 详细信息

现行《水利工程施工监理规范》(SL288-2014)在条文说明中首次引用了专项检测的概念,规定了专项检测实施内容,但未对专项检测进行定义,也未制定专项检测的项目、频率及程序,因此专项检测在水利工程中实施效果并不十分理想。本文从专项检测频率、检测费用及检测程序三个方面入手,在总结水利工程及其他行业质量检测频率、检测内容及经验的基础上,提出了针对水利工程施工质量的专项检测实施项目、检测频率及程序,为专项检测在水利工程的推广运用提供参考。

关键词：水利工程专项检测质量控制施工监理