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Science china Earth Sciences 2010年第5期53卷 657-664页

作者： zhai qingguo1 wang jun1, li cai2.& su li3 1 institute of geology, Chinese Academy of Geological Sciences,{2., china 2.College of Earth Sciences, Jilin University, Changchun 130061, china 3 The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources, china University of Geo- sciences, beijing 100083, china institute of geology Chinese Academy of Geological Sciences Beijing China College of Earth Sciences Jilin University Changchun China The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.2.2.15 to 0.2.2.57, with εHf(t) values of 5.02.0.2., indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro SHRIMP dating Hf isotope

SHRIMP U-Pb dating and Hfisotopic analyses of zircons from the mafic dyke swarms in central Qiangtang area,Northern Tibet

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Chinese Science Bulletin 2009年第21期54卷 2279-2285页

作者： zhai qingguo {2. cai {2. jun JI ZhanSheng {2. Yong institute of geology Chinese Academy of Geological Sciences Beijing 100037 China College of Earth Sciences Jilin University Changchun 130061 China

In the "Central Uplift" of Qiangtang,Northern Tibet,a large scale of mafic dyke swarms extended in E-W *** SHRIMP U-Pb dating on two representative samples of diabase dyke yield weighted mean ages of 2.4 ± 3 Ma and 302.± 4 Ma,respectively,suggesting they emplaced in the Late Carboniferous to Early *** 176Hf/177Hf ratios range from 0.2.2.52.to 0.2.3041,with εHf(t) values of +12.1 to +12.2.and Hf modal(TDM) ages of ～440―460 *** data indicate that these mafic dykes were mainly derived from the depleted *** addition,geochemical data suggest that these mafic dyke swarms are ofintra-plate ***,the mafic dyke swarms represent products during the extensional process associated with the opening of the Paleo-Tethys Ocean in the area.

关键词：锆石SHRIMP 镁铁质岩墙群同位素分析中部地区羌塘 Pb 藏北平均年龄

CEPC Technical Design Report

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Radiation Detection Technology and Methods 2024年第1期8卷 I0003-I0016,1-1091页

作者： Waleed Abdallah Tiago Carlos Adorno de Freitas Konstantin Afanaciev Shakeel Ahmad Ijaz Ahmed Xiaocong Ai Abid Aleem Wolfgang Altmannshofer Fabio Alves Weiming An Rui An Daniele Paolo Anderle Stefan Antusch Yasuo Arai Andrej Arbuzov Abdesslam Arhrib Mustafa Ashry Sha Bai Yu Bai Yang Bai Vipul Bairathi Csaba Balazs Philip Bambade Yong Ban Tripamo Bandyopadhyay Shou-Shan Bao Desmond P.Barber Ayse Bat Varvara Batozskaya subash Chandra Behera Alexander Belyaev Michele Bertucci Xiao-jun Bi Yuanjie Bi Tianjian Bian Fabrizio Bianchi Thomas Biekotter Michela Biglietti Shalva Bilanishvili Deng Binglin Denis Bodrov Anton Bogomyagkov Serge Bondarenko Stewart Boogert Maarten Boonekamp Marcello Borri Angelo Bosotti Vincent Boudry Mohammed Boukidi Igor Boyko Ivanka Bozovic Giuseppe Bozzi Jean-Claude Brient Anastasiia Budzinskaya Masroor Bukhari Vladimir Bytev Giacomo Cacciapaglia Hua cai Wenyong cai Wujun cai Yijian cai Yizhou cai Yuchen cai Haiying cai Huacheng cai Lorenzo Calibbi junsong Cang Guofu Cao Jianshe Cao Antoine Chance Xuejun Chang Yue Chang Zhe Chang Xinyuan Chang Wei Chao Auttakit Chatrabhuti Yimin Che Yuzhi Che Bin Chen Danping Chen Fuqing Chen Fusan Chen Gang Chen Guoming Chen Hua-Xing Chen Huirun Chen Jinhui Chen Ji-Yuan Chen Kai Chen Mali Chen Mingjun Chen Mingshui Chen Ning Chen Shanhong Chen Shanzhen Chen Shao-Long Chen Shaomin Chen Shiqiang Chen Tianlu Chen Wei Chen Xiang Chen Xiaoyu Chen Xin Chen Xun Chen Xurong Chen Ye Chen Ying Chen Yukai Chen Zelin Chen Zilin Chen Gang Chen Boping Chen Chunhui Chen Hok Chuen Cheng Huajie Cheng Shan Cheng Tongguang Cheng Yunlong Chi Pietro Chimenti Wen Han Chiu Guk Cho Ming-Chung Chu Xiaotong Chu Ziliang Chu Guglielmo Coloretti Andreas Crivellin Hanhua Cui Xiaohao Cui Zhaoyuan Cui Brunella D'Anzi ling-Yun Dai Xinchen Dai Xuwen Dai Antonio De Maria Nicola De Filippis Christophe De La Taille Francesca De Mori Chiara De Sio Elisa Del Core Shuangxue Deng Wei-Tian Deng Zhi Deng Ziyan Deng Bhupal Dev Tang Dewen Biagio Di Micco Ran Ding Siqin Dingl Yadong Ding Haiyi Dong Jianin AGH University of Science and Technology Faculty of Physics and Applied Computer ScienceKrakow Anhui University HefeiAnhui Applied Physics Department Federal Urdu University of ArtsScience and TechnologyIslamabad Banaras Hindu University Institute of ScienceVaranasi Bandirma Onyedi Eylul University Bandirma Beihang University Beijing beijing Computational Science Research Center Beijing beijing Conveyi LTD Beijing beijing Glass Research institute Co. LtdBeijing beijing institute of Technology Beijing beijing Normal University Beijing Brown University ProvidenceRI Budker institute of Nuclear Physics Novosibirsk Cadi Ayyad University Laboratory of Fundamental and Applied PhysicsPolydisciplinary FacultyMarrakech cairo University Giza Center for Theory and Computation National Tsing Hua UniversityHsinchu Central china Normal University WuhanHubei Central South University ChangshaHunan Centro de Fisica Teorica de Particulas Universidade Tecnica de LisboaLisboa Chengdu KaitengSifang Digital Radio&TV Equipment Co. LtdChengduSichuan china academy of engineering physics MianyangSichuan china building materials academy Beijing china Center of Advanced Science and Technology Beijing china institute of Atomic Energy Beijing china Jiliang University HangzhouZhejiang china Nuclear Instrument CO. LTDBeijing china University of Geosciences Beijing china University of Geosciences WuhanHubei china University of Mining and Technology XuzhouJiangsu china West Normal University NanchongSichuan Chongqing University Department of PhysicsChongqing Chulalongkorn University Bangkok City University of Hong Kong Department of PhysicsHong Kong Cockcroft institute Daresbury Cornell University IthacaNY CPPM(AMU/IPhU&CNRS/INP) Marseille Dalian Minzu University DalianLiaoning Dalian University of Technology Department of PhysicsDalian Deutsches Elektronen-Synchrotron DESY Hamburg Dzhelepov Laboratory of Nuclear Problems of Joint institute for Nuclear Research(DLNP JINR) Dubna East china University Of Science And Technol

The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by china,fostered through extensive collaboration with international *** complex comprises four accelerators:a 30 GeV linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs *** its baseline design with synchrotron radiation(SR)power of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2.s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs *** the SR power to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of *** Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2.15)and the Conceptual Design Report(CDR,2.18),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering ***,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection *** is anticipated to begin around 2.2.-2.2.,pending government approval,with an estimated duration of 8 *** commencement of experiments and data collection could potentially be initiated in the mid-2.30s.

关键词： initiated exceeding precise

The first data release(DR1) of the LAMOST regular survey

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Research in Astronomy and Astrophysics 2015年第8期15卷 1095-1124页

作者： A-li Luo Yong-Heng Zhao Gang Zhao li-{2. Deng Xiao-Wei liu Yi-Peng Jing Gang wang Hao-Tong Zhang Jian-Rong Shi Xiang-Qun Cui Yao-Quan Chu Guo-Ping li Zhong-Rui Bai Yue Wu Yan {2. Shu-Yun Cao Zi-Huang Cao Jeffrey L.Carlin Hai-Yuan Chen Jian-jun Chen Kun-Xin Chen li Chen Xue-Lei Chen Xiao-Yan Chen Ying Chen Norbert Christlieb Jia-Ru Chu Chen-Zhou Cui Yi-Qiao Dong Bing Du Dong-Wei Fan Lei Feng Jian-Ning Fu Peng Gao Xue-Fei Gong Bo-Zhong Gu Yan-Xin Guo Zhan-Wen Han Bo-liang He Jin-liang Hou Yong-Hui Hou Wen Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Zhi-Ying Huo Lei Jia Fang-Hua Jiang Xiang Jiang Zhi-Bo Jiang Ge Jin Xiao Kong Xu Kong Ya-Juan Lei Ai-Hua li Chang-Hua li Guang-Wei li Hai-Ning li Jian li Qi li Shuang li Sha-Sha li Xin-Nan li Yan li Yin-Bi li Ye-Ping li Yuan liang Chien-Cheng lin Chao liu Gen-Rong liu Guan-Qun liu Zhi-Gang liu Wen-Zhi Lu Yu Luo Yin-Dun Mao Heidi Newberg Ji-jun Ni Zhao-Xiang Qi Yong-jun Qi Shi-Yin Shen Huo-Ming Shi Jing Song Yi-Han Song Ding-Qiang su Hong-jun su Zheng-Hong Tang Qing-Sheng Tao Yuan Tian Dan wang Da-Qi wang Feng-Fei wang Guo-Min wang Hai wang Hong-Chi wang Jian wang Jia-Ning wang Jian-ling wang Jian-Ping wang jun-Xian wang Lei wang Meng-Xin wang Shou-Guan wang Shu-Qing wang Xia wang Ya-Nan wang You wang Yue-Fei wang You-Fen wang Peng Wei Ming-Zhi Wei Hong Wu Ke-Fei Wu Xue-Bing Wu Yu-Zhong Wu Xiao-Zheng Xing ling-Zhe Xu Xin-Qi Xu Yan Xu Tai-Sheng Yan De-Hua Yang Hai-Feng Yang Hui-Qin Yang Ming Yang Zheng-Qiu Yao Yong Yu Hui Yuan Hai-Bo Yuan Hai-Long Yuan Wei-Min Yuan Chao {2.} En-Peng Zhang Hua-Wei Zhang Jian-Nan Zhang li-Pin Zhang Wei Zhang Yong Zhang Yan-Xia Zhang Zheng-Chao Zhang Ming Zhao Fang Zhou Xu Zhou Jie Zhu Yong-Tian Zhu Si-Cheng Zou Fang Zuo National Astronomical Observatories Chinese Academy of Sciences Department of Astronomy Peking University Shanghai Astronomical Observatory Chinese Academy of Sciences Nanjing institute of Astronomical Optics & Technology National Astronomical ObservatoriesChinese Academy of Sciences University of Science and Technology of china Department of Physics Applied Physics and AstronomyRensselaer Polytechnic InstituteTroyNY 12180USA Department of Physics and Astronomy Earlham CollegeRichmondIN 47374USA Universitt Heidelberg Zentrum für AstronomieLandessternwarteKnigstuhl 1269117 HeidelbergGermany Department of Astronomy Beijing Normal University Yunnan Observatories Chinese Academy of Sciences Purple Mountain Observatory Chinese Academy of Sciences

The Large sky Area Multi-Object Fiber Spectroscopic Telescope（LAMOST） general survey is a spectroscopic survey that will eventually cover approximately half of the celestial sphere and collect 10 mil{2.on spectra of stars, galaxies and QSOs. Objects in both the pilot survey and the first year regular survey are included in the LAMOST DR1. The pilot survey started in October 2.11 and ended in june 2.12. and the data have been released to the pub{2.c as the LAMOST Pilot Data Release in August 2.12. The regular survey started in September 2.12. and completed its first year of operation in june 2.13. The LAMOST DR1 includes a total of 12.2.plates containing 2.955 336 spectra, of which 1 790 879 spectra have observed signalto-noise ratio（SNR） ≥ 10. All data with SNR ≥ 2.are formally released as LAMOST DR1 under the LAMOST data po{2.cy. This data release contains a total of 2.2.4 696 spectra, of which 1 944 32. are stellar spectra, 12.082.are galaxy spectra and 5017 are quasars. The DR1 not only includes spectra, but also three stellar catalogs with measured parameters： late A,FGK-type stars with high qua{2.ty spectra（1 061 918 entries）, A-type stars（100 073 entries）, and M-type stars（12. 52. entries）. This paper introduces the survey design, the observational and instrumental {2.mitations, data reduction and analysis, and some caveats. A description of the FITS structure of spectral files and parameter catalogs is also provided.

关键词： techniques: spectroscopic survey—data release—catalog

An overview of the resources and environment conditions and major geological problems in the Yangtze River economic zone, china

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china geology 2018年第3期1卷 435-449页

作者： Yue-hua Jiang liang-jun lin li-de Chen Hua-yong Ni Wei-ya Ge Hang-xin Cheng Gang-yi zhai Gui-ling wang Yi-zhong Ban Yuan li Ming-tang Lei Cheng-xuan Tan Jing-wen su Quan-ping Zhou Tai-li Zhang Yun li Hong-ying liu Ke Peng Han-mei wang Nanjing Geological survey Center China Geological SurveyNanjing 210016China institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Shanghai Geological survey Research institute Shanghai 200072China china Geological survey Water Ring Department Beijing 100037China Wuhan Geological survey Center of china Geological survey Wuhan 430205China Chengdu Geological survey Center China Geological SurveyChengdu 610081China Geophysical and Geochemical Exploration Chinese Academy of Geological SciencesLangfang 065000China Oil and Gas survey China Geological SurveyBeijing 100029China institute of Hhydrogeology and Hnvironmental geology Chinese Academy of Geological SciencesShijiazhuang 050061China china institute of Geo-environmental Monitoring Beijing 100081China institute of Karst geology Chinese Academy of Geological SciencesGuilin 541004China

Focusing on the Yangtze River economic zone,the previous geological researches are systematically summarized,resources and environment conditions and major geological problems which are needing to be concerned in land planning and construction are *** results show that the resource conditions of cultivated land,shale gas,geotherm,{2.thium and so on are superior in the Yangtze River economic zone,and the resources and environment conditions are conducive to develop the modern agriculture,clean energy industry and strategic emerging industries.3×1013 m^2.farmlands without heavy metal pollution are concentrated;there are three national level shale gas exploration and development bases with explored reserves of 5.441×1011 m^3;geothermal availabi{2.ty is 2.4×109 t of standard coal each year,equivalent to 19% of the amount of coal in 2.14;Asia's largest energy {2.thium metal ore deposit is *** some parts of Yangtze River economic zone,there are some major geological problems such as active faults,karst collapse,ground subsidence,lands{2.de-collapse-debris flow,affecting the river-crossing channels,high-speed railway,urban agglomeration and green ecological corridor planning and *** problems should be concerned,and the relevant suggestions and countermeasures are put ***,the ideas to further support the development of the Yangtze River economic zone are put forward.

关键词： The Yangtze River economic zone Resources and environment conditions Major geological problems Environmental geology Hydrogeology Disaster geology

sub-percent precision measurement of neutrino oscillation parameters with {2.O

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Chinese Physics C 2022年第12期46卷 28-49页

作者： Angel Abusleme Thomas Adam Shakeel Ahmad Rizwan Ahmed Sebastiano Aiello Muhammad Akram Abid Aleem Fengpeng An Qi An Giuseppe Andronico Nikolay Anfimov Vito Antonelli Tatiana Antoshkina Burin Asavapibhop João Pedro Athayde Marcondes de André Didier Auguste Weidong Bai Nikita Balashov Wander Baldini Andrea Barresi Davide Basilico Eric Baussan Marco Bellato Antonio Bergnoli Thilo Birkenfeld Sylvie Blin David Blum Simon Blyth Anastasia Bolshakova Mathieu Bongrand Clément Bordereau Dominique Breton Augusto Brigatti Riccardo Brugnera Riccardo Bruno Antonio Budano Jose Busto Ilya Butorov Anatael Cabrera Barbara Caccianiga Hao cai Xiao cai Yanke cai Zhiyan cai Riccardo Callegari Antonio Cammi Agustin Campeny Chuanya Cao Guofu Cao jun Cao Rossella Caruso Cédric Cerna Chi Chan Jinfan Chang Yun Chang Guoming Chen Pingping Chen Po-An Chen Shaomin Chen Xurong Chen Yixue Chen Yu Chen Zhiyuan Chen Zikang Chen Jie Cheng Yaping Cheng Yu Chin Cheng Alexey Chetverikov Davide Chiesa Pietro Chimenti Artem Chukanov Gérard Claverie Catia Clementi Barbara Clerbaux Selma Conforti Di Lorenzo Daniele Corti Flavio Dal Corso Olivia Dalager Christophe De La Taille Zhi Deng Ziyan Deng Wilfried Depnering Marco Diaz Xuefeng Ding Yayun Ding Bayu Dirgantara Sergey Dmitrievsky Tadeas Dohnal Dmitry Dolzhikov Georgy Donchenko Jianmeng Dong Evgeny Doroshkevich Marcos Dracos Frédéric Druillole Ran Du Shuxian Du Stefano Dusini Martin Dvorak Timo Enqvist Heike Enzmann Andrea Fabbri Donghua Fan Lei Fan Jian Fang Wenxing Fang Marco Fargetta Dmitry Fedoseev Zhengyong Fei li-Cheng Feng Qichun Feng Richard Ford Amélie Fournier Haonan Gan Feng Gao Alberto Garfagnini Arsenii Gavrikov Marco Giammarchi Nunzio Giudice Maxim Gonchar Guanghua Gong Hui Gong Yuri Gornushkin Alexandre Göttel Marco Grassi Vasily Gromov Minghao Gu Xiaofei Gu Yu Gu Mengyun Guan Yuduo Guan Nunzio Guardone Cong Guo Jingyuan Guo Wanlei Guo Xinheng Guo Yuhang Guo Paul Hackspacher Caren Hagner Ran Han Yang Han Miao He Wei He Tobias Heinz Patrick Hellmuth Yuekun Heng Rafael Herrera YuenKeung Ho Yerevan Physics institute YerevanArmenia Universiélibre de Bruxelles BrusselsBelgium Universidade Estadual de Londrina LondrinaBrazil Pontificia Universidade Catolica do Rio de Janeiro Rio de JaneiroBrazil Pontificia Universidad Católica de Chile SantiagoChile Universidad Tecnica Federico Santa Maria ValparaisoChile beijing institute of Spacecraft Environment Engineering BeijingChina beijing Normal University BeijingChina china institute of Atomic Energy BeijingChina institute of High Energy Physics BeijingChina North china Electric Power University BeijingChina School of Physics Peking UniversityBeijingChina Tsinghua University BeijingChina University of Chinese Academy of Sciences BeijingChina Jilin University ChangchunChina College of Electronic Science and Engineering National University of Defense TechnologyChangshaChina Chongqing University ChongqingChina Dongguan University of Technology DongguanChina Jinan University GuangzhouChina sun Yat-Sen University GuangzhouChina Harbin institute of Technology HarbinChina University of Science and Technology of china HefeiChina The Radiochemistry and Nuclear Chemistry Group in University of South china HengyangChina Wuyi University JiangmenChina Shandong University JinanChinaand Key Laboratory of Particle Physics and Particle Irradiation of Ministry of EducationShandong UniversityQingdaoChina institute of Modern Physics Chinese Academy of SciencesLanzhouChina Nanjing University NanjingChina Guangxi University NanningChina East china University of Science and Technology ShanghaiChina School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao Lee institute Shanghai Jiao Tong UniversityShanghaiChina institute of Hydrogeology and Environmental geology Chinese Academy of Geological SciencesShijiazhuangChina Nankai University TianjinChina Wuhan University WuhanChina Xi'an Jiaotong University Xi'anChina Xiamen University XiamenChina School of Physics and Microelectronics Zhengzhou UniversityZhengzhou

junO is a multi-purpose neutrino observatory under construction in the south of *** publication presents new sensitivity estimates for the mea{2.rement of the △m_(31)^(2.,△m_(2.)^(2.,sin^(2.θ_(12.,and sin^(2.θ_(13) oscillation parameters using reactor antineutrinos,which is one of the primary physics goals of the *** sensitivities are obtained using the best knowledge available to date on the location and overburden of the experimental site,the nuclear reactors in the {2.rrounding area and beyond,the detector response uncertainties,and the reactor antineutrino spectral shape constraints expected from the TAO satellite *** is found that the △m_(2.)^(2. and sin^(2.θ_(12. oscillation parameters will be determined to 0.5%precision or better in six years of data *** the same period,the △m_(31)^(2. parameter will be determined to about 0.2.precision for each mass ordering *** new precision represents approximately an order of magnitude improvement over existing constraints for these three parameters.

关键词： neutrino oscillation reactor antineutrino precision measurement junO

上黑龙江盆地前哨林场黑云母二长花岗岩锆石U-Pb年龄、地球化学特征及地质意义

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地球学报 2023年第6期44卷 1017-1035页

作者：巩鑫张志博杜蔺蔡国盛宋小军曾凡祥李光春苏永虎但仕生赵元艺贵州省有色金属和核工业地质勘查局地质矿产勘查院贵州贵阳550005 黑龙江省第五地质勘查院黑龙江哈尔滨150090 中国地质科学院矿产资源研究所北京100037

上黑龙江盆地前哨林场位于兴蒙造山带东段额尔古纳微地块北缘,北与西伯利亚古陆以蒙古—鄂霍次克缝合带相隔,东以塔源—喜桂图断裂与兴安地块相邻。本文通过对上黑龙江盆地前哨林场黑云母二长花岗岩进行锆石U-Pb年龄、主微量及同位素地... 详细信息

上黑龙江盆地前哨林场位于兴蒙造山带东段额尔古纳微地块北缘,北与西伯利亚古陆以蒙古—鄂霍次克缝合带相隔,东以塔源—喜桂图断裂与兴安地块相邻。本文通过对上黑龙江盆地前哨林场黑云母二长花岗岩进行锆石U-Pb年龄、主微量及同位素地球化学系统研究,为探讨早古生代额尔古纳微地块与相邻地块的碰撞机制提供理论依据。利用LA-ICP-MS锆石U-Pb同位素测定技术,获得研究区黑云母二长花岗岩结晶年龄为(458.4±2.4)Ma(MSWD=0.02.),确定了岩体形成时代为早古生代中—晚奥陶纪。岩石中锆石Hf同位素ɛHf(t)值介于–4.64~1.84,其测点大部分位于球粒陨石演化线之下,两阶段模式年龄(tDM2.介于715~112. Ma。地球化学显示岩石具有富硅、富铝、富碱等特征;稀土配分曲线表现出轻稀土(LREE)相对富集,重稀土(HREE)相对亏损的右倾特征,且岩石相对富集大离子亲石元素Rb、K及高场强元素Th、U、Zr、Hf,相对亏损大离子亲石元素Ba、Sr及高场强元素Nb、Ta、P、Ti。岩石成因类型判别图显示前哨林场黑云母二长花岗岩具A型花岗岩特征,岩石Hf同位素及微量元素特征显示岩体岩浆来源于中—新元古代古老地壳的熔融,且存在少许幔源物质及新增生地壳物质熔融的参与,元素特征暗示岩石形成于额尔古纳地块与西伯利亚古陆碰撞后的伸展构造环境背景下。结合前人对额尔古纳地块早古生代花岗岩形成背景的研究,认为额尔古纳地块北缘及东北缘早古生代花岗岩形成机制不同,前者形成于额尔古纳地块与西伯利亚古陆及蒙古—图瓦地块碰撞、拼接后伸展背景下;后者主要形成于额尔古纳与兴安地块碰撞伸展背景下。

关键词： LA-ICP-MS 锆石U-Pb年龄 Hf同位素地球化学黑云母二长花岗岩前哨林场上黑龙江盆地

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