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Benthic foraminiferal fauna turnover at 2.1 Ma in the northern South china Sea

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Chinese Science Bulletin 2007年第6期52卷 839-843页

作者： huang baoqi {2. zhimin wang pinxian school of earth and {2. sciences Peking University Beijing 100871 China Laboratory of Marine Geology Tongji University Shanghai 200092 China

Quantitative analysis of benthic foraminifera from ODP Site 1146 in the northern South china Sea (SCS) shows that abundance of Bulimina alazanensis, sometimes up to about 90%, decreased gradually since 3.2.Ma, especially at 2.1 Ma. Abundance of other benthic foraminiferal species, Globobulimina sub-globosa and Cibicidoides wuellerstorfi, increased after 2.1 Ma. Comparison with changes in oxygen and carbon isotopes of planktonic and benthic foraminifera shows that high abundance values of B. alazanensis corresponded with lower values of oxygen isotope, but for carbon isotope, high values of the species were consistent with heavier carbon isotope of benthic foraminifera and lighter carbon isotope of planktonic foraminifera, respectively, and vice versa. Considering factors such as uplift of Bashi Strait, expansion of the North Hemisphere Glaciation, strengthening of East Asian winter mon-soon and variations in oxygen and carbon isotope of foraminifera, changes of B. alazanensis in ODP Site 1146 suggest that the source of deep water masses of the northern South china Sea changed from the warm Pacific deep water with high oxygen content to Pacific Intermediate water with low oxygen content at 2.1 Ma. In addition, the strengthened East Asian winter monsoon resulted in increased pri-mary productivity, high nutrient and suboxic bottom water. Variations in species of B. alazanensis seemed to be unable to tolerate environmental stress induced by deep water masses and productivity changes.

关键词：南海北部深海海底有孔虫区系晚上新世古海洋学

Mobilization of Cu in the continental lower crust:A perspective from Cu isotopes

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Geoscience Frontiers 2023年第5期14卷 17-38页

作者： Chen-Hao Luo Rui wang Yun Zhao jian {2. Noreen J.Evans State Key Laboratory of Geological Processes and Mineral Resources and Institute of Earth SciencesChina University of GeosciencesBeijing 100083China State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjingChina SinoProbe Laboratory of Chinese Academy of Geological sciences BeijingChina State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China John de Laeter Centre Curtin UniversityGPO Box U1987PerthWA 6845Australia

Recent studies have shown that Cu-rich sulfide accumulates in the lower continental crust and serves as a critical reservoir to balance Cu depletion in the upper *** of Cu in the lower crust is also assumed to be a major metal source for non-arc setting porphyry Cu *** test this hypothesis and further explore the behavior of Cu in the lower crust,we analyzed the elemental and Cu isotopic compositions of lower crustal rocks from different geological *** collected samples include hornblendites from the Kohistan arc,granulite xenoliths and hornblendites from the Gangdese arc,hornblendites and gabbros from the Laiyuan complex in the North china Craton,and hornblendite xenoliths from the western margin of the Yangtze *** lower crustal rocks have experienced varying degrees of primary or secondary sulfide accumulation,with significantly varied Cu contents(11.2.to 145 ppm)andδδ^(65)(1.05‰to 1.40‰).Petrography and geochemistry reveal varying degrees of metasomatism and fluid interaction in these rocks,and based on this,they can be further divided into three groups:Group I includes the Gangdese granulites and Yunnan hornblendites,which perhaps experienced significant *** suite of rocks shows enrichment ofδ^(65)(dδ^(65)=0.01‰to 1.40‰),positively correlated with metasomatism(dδ^(65)***/Pb).We suggest the secondary sulfides which transformed from sulfates during the interaction between lower crust and arc magma are dominant in these rocks,so the feature of heavy isotope enrichment is *** II includes Laiyuan hornblendites and gabbros,derived from the same parental magma and emplaced at different depths(hornblendites,2..3–2..1 km;gabbros 8.4–11.1 km).The Cu isotopic compositions are strongly fractionated between these two kinds of rocks,with low dδ^(65)in the hornblendites(0.00‰to 0.2.‰)and highly polarized dδ^(65)in the gabbros(1.05‰to 0.81‰).Geochemical indicators and mineral assemblages reveal that fluid intera

关键词： Cu isotope of lower continental crust Cu mobilization Metasomatism Fluid interaction Partial melting

高寒草甸退化过程中群落生产力和物种多样性的非线性响应机制研究

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植物生态学报 2018年第1期42卷 50-65页

作者：陈宁张扬建朱军涛李军祥刘瑶杰俎佳星丛楠黄珂王荔中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室拉萨高原生态试验站北京100101 中国科学院大学北京100190 中国科学院青藏高原地球科学卓越创新中心北京100101 中国科学院大学资源与环境学院北京100190 北京大学深圳研究生院深圳518055

为了阐释青藏高原高寒草甸退化的关键生态过程,该研究依托藏北高原草地生态系统研究站(那曲站),设置不同退化梯度实验,即对照、轻度退化、中度退化、重度退化和极度退化5个梯度,探究群落生产力和物种多样性对不同退化强度的响应机制。... 详细信息

为了阐释青藏高原高寒草甸退化的关键生态过程,该研究依托藏北高原草地生态系统研究站(那曲站),设置不同退化梯度实验,即对照、轻度退化、中度退化、重度退化和极度退化5个梯度,探究群落生产力和物种多样性对不同退化强度的响应机制。结果表明:1)随着退化程度不断加剧,地上生物量呈现线性或非线性增加趋势,在重度退化处理下,地上生物量显著高于对照32.3%,其中高山嵩草(Kobresia pygmaea)地上生物量呈非线性下降趋势,而矮火绒草(Leontopodium nanum)地上生物量呈非线性增加趋势;2.与地上生物量的响应模式相反,随着退化程度加剧,地下生物量与总生物量均呈现非线性降低趋势;3)高寒草甸退化过程中,物种辛普森指数、丰富度指数、香农多样性指数和均匀度指数均呈现非线性上升趋势。结构等式方程结果表明,土壤碳含量和体积含水量与地下生物量均呈现显著的正相关关系。土壤碳含量、体积含水量和砾石质量比对地上生物量无显著影响,土壤碳、氮含量与物种多样性指数呈现显著的负相关关系。研究认为地上生产力的变化不能很好地指示草地的退化程度,建议今后研究应以可食性牧草和毒杂草等植物功能群的变化来衡量草地退化。

关键词：高寒草甸退化梯度物种多样性生产力非线性响应

In situ stress state and seismic hazard in the Dayi seismic gap of the Longmenshan thrust belt

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Science china earth {2. 2022年第7期65卷 1388-1398页

作者： Bing LI Furen XIE Jinshui huang Xiwei XU Qiliang GUO Guangwei ZHANG Junshan XU jianxin {2. Dawei jianG jian {2. Lifeng DING school of earth and {2. sciences University of Science and Technology of ChinaHefei 230026China National Institute of Natural Hazards Ministry of Emergency ManagementBeijing 100085China

In the Longmenshan thrust belt,the Dayi seismic gap,an area with few earthquakes,is located between the ruptures of the 2.08 Wenchuan earthquake and the {2.3 Lushan earthquake,with a length of approximately 40–60 *** date,however,the extent of the seismic hazard of the Dayi seismic gap and whether this gap is under high stress are still hotly *** further evaluate the seismic hazard of the Dayi seismic gap with regard to stress,two boreholes(1,000 and 500 m deep)were arranged to carry out hydraulic fracturing in situ stress measurement on either side of the Shuangshi-Dachuan fault *** zone has a high seismic hazard and the capacity to undergo surface *** the analogy of this new data with stability analysis using Byerlee’s Law and existing stress measurement data collected before strong earthquakes,the results show that the area surrounding the Shuangshi-Dachuan fault zone in the Dayi seismic gap(Dachuan Town)is in a state of high in situ stress,and has the conditions necessary for friction slip,with the potential hazard of moderate to strong *** results are the first to reveal the in situ stress profile at a depth of 1,000 m in the Dayi seismic gap,and provide new data for comprehensive evaluation of the seismic hazard in this seismic gap,which is of great significance to explore the mechanism of earthquake occurrence and to help mitigate future disaster.

关键词： Dayi seismic gap Wenchuan earthquake Lushan earthquake In situ stress state Byerlee criterion Fault stability

Carbonated Big Mantle Wedge Extending to the NE Edge of the Stagnant Pacific Slab:Constraints from Late Mesozoic-Cenozoic Basalts from Far Eastern Russia

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Journal of earth Science 2022年第1期33卷 121-132页

作者： Ronghua Cai Shan Xu Dmitri AIonov jian huang Sheng-Ao Liu Shuguang Li Jingao Liu State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China Géosciences Montpellier Universitéde Montpellier34095 MontpellierFrance CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

It has been suggested that the carbonated mantle reflected by Mg-Zn isotopic anomalies of Cenozoic intraplate basalts from East Asia coincides with the stagnant West Pacific slab in the mantle transition ***,the northern boundary of such carbonated domain beneath East Asia is *** Mesozoic-Cenozoic intraplate basalts are widespread in far eastern Russia and thus provide an opportunity to examine this *** we report major-trace element contents and Sr-NdMg-Zn isotopic compositions for 9 Late Mesozoic-Cenozoic basaltic samples from the Khanka Block and Sikhote-Alin accretionary *** are characterized by large variations in SiO_(2.contents(41 wt.%to 50 wt.%)and CaO/Al_(2.O_(3)(0.50 to 0.97),enrichments of large-ion lithophile elements(LILE),positive Nb-Ta anomalies and strongly negative K,Pb,Zr,Hf,Ti,Y anomalies in primitive mantle-normalized trace element spider ***,the rocks show good correlations of Ti/Ti^(*)with Hf/Hf^(*),La/Yb,Fe/Mn and trace element contents(e.g.,Nb).In addition,they have lighter Mg and heavier Zn isotope compositions than the BSE estimates,coupled with depleted Sr-Nd isotope *** elemental and isotopic characteristics cannot be explained by alteration,magma differentiation or diffusion,but are consistent with the partial melting of carbonated *** and large,the Late Mesozoic-Cenozoic basalts from far eastern Russia bear very similar geochemical characteristics as those Na-series Cenozoic basalts from eastern *** extended region of Mg-Zn isotopic anomalies is roughly coincident with the stagnant West Pacific slab beneath East Asia,and all of these alkali basalts can be generated from mantle sources hybridized by recycled Mg-carbonates from the Pacific slab stagnant in the mantle transition *** infer that(1)the carbonated big mantle wedge extends to the NE edge of the West Pacific slab and may have also appeared in the Late Mesozoic due to the effect of the Paleo-Pac

关键词： Mg-Zn isotopes deep carbon cycling far eastern Russia isotopes big mantle wedge

搜寻第二个地球——系外地球(ET)巡天计划

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空间科学学报 2024年第3期44卷 400-424页

作者：葛健陈雯陈永和宋宗玺王坚张辉李岩臧伟呈周丹张永帅陈琨阳应权毛淑德黄煦药新雨李兴隆姜海娇于涌唐正宏董峰高伟张鸿飞申超王峰涛魏传新杨宝玉李豫东文林张朋军张聪聪谢基伟马波邓洪平刘慧根段旭亮王昊宇黄江江高扬王伊菲王磊秦根健刘欣宇高婕中国科学院上海天文台上海200030 中国科学院微小卫星创新研究院上海201304 中国科学院上海技术物理研究所上海200083 中国科学院西安光学精密机械研究所西安710119 中国科学技术大学合肥230026 清华大学天文系北京100190 南昆士兰大学天体物理中心图文巴QLD4350 中国航天科技集团公司第八研究院803研究所上海201109 中国科学院新疆理化技术研究所乌鲁木齐830011 南京大学天文系南京210023 中山大学物理与天文学院珠海519082

系外地球科学卫星(ET)将通过采用空间大视场超高精度测光这一关键技术在国际上率先突破生命起源中的系外地球存在及其演化这一重大前沿科学问题. ET卫星将在日地拉格朗日L2.晕(Halo)轨道部署由6台广角凌星望远镜和1台微引力透镜望远镜... 详细信息

系外地球科学卫星(ET)将通过采用空间大视场超高精度测光这一关键技术在国际上率先突破生命起源中的系外地球存在及其演化这一重大前沿科学问题. ET卫星将在日地拉格朗日L2.晕(Halo)轨道部署由6台广角凌星望远镜和1台微引力透镜望远镜构成的空间天文台,结合凌星法和微引力透镜法,利用空间超大视场和超高精度的光学测光观测,首次发现富有重要意义、被广泛关注的系外地球,并确定其发生率,对目前了解甚少的类地行星和流浪行星进行国际上第一次大规模的种群普查,首次发现流浪地球,并确定其发生率,揭示类地行星和流浪行星起源,为地外生命探寻提供候选者和新方向. ET卫星的观测结果、统计研究以及和对理论的检验将回答系外地球在宇宙中有多普遍,类地行星是如何形成和演化的,流浪行星又是如何起源的这些亟待解决的前沿科学问题.对ET卫星发现的系外地球样本的后随观测,将精确测量其质量、密度和大气成分,有助于深入分析宜居性特征.此外,对ET新发现的大量各种系外行星样本的研究,以及对理论的检验将推动这些种类的行星形成和演化规律的更深入认识, ET的大量高精度、高频次和长基线测光数据将推动星震学、银河系考古学、时域天文学、双星和双星黑洞等领域的研究.

关键词：系外行星类地行星宜居带凌星微引力透镜测光

Advances in the Researches of the Middle and Upper Atmosphere in china in 2.2.-2.2.

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空间科学学报 2022年第4期42卷 684-711页

作者： CHEN Zeyu XU Jiyao CHEN Hongbin CHEN Wen REN Rongcai HU Xiong ZHU Yajun XUE Xianghui LU Gaopeng ZHANG Shaodong huang Kaiming TIAN Wenshou ZHANG jiankai HU Dingzhu RAO jian HU Yongyun XIA Yan Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029 National space Science Center Chinese Academy of SciencesBeijing 100190 school of earth and {2. sciences University Science and Technology of ChinaHefei 230026 school of Electronic Information Wuhan UniversityWuhan 430072 College of Atmospheric Science Lanzhou UniversityLanzhou 730000 Nanjing University of Information Science and Technology Nanjing 210044 school of earth and {2. sciences Peking UniversityBeijing 100871 Key Laboratory of Atmospheric Optics Anhui Institute of Optics and Fine MechanicsHFIPSChinese Academy of SciencesHefei 230031 University of the Chinese Academy of sciences Beijing 100049

This report reviews the researches for the middle and upper atmosphere in 2.2.-2.2. by Chinese *** report consists of five parts introducing primarily the results from the aspects of the development of infrastructure,the structure and composition,the climate and modeling,the dynamics for the middle and upper atmosphere,and Coupling between Stratosphere and Troposphere,respectively.

关键词： Middle and upper atmosphere Structure and composition Climate Dynamics

一种基于AMSR-E和ASAR数据的土壤水分协同反演方法

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北京大学学报（自然科学版） 2016年第5期52卷 902-910页

作者：李新曾琪明王心逸黄江辉焦健北京大学地球与空间科学学院遥感与地理信息系统研究所北京100871

在缺乏卫星过境时地面同步观测数据的情况下,大范围高时空分辨率的土壤水分监测存在一定的困难。针对这一问题,提出一种不依赖地面土壤水分同步观测数据的主、被动微波协同反演逐日高空间分辨率的土壤水分观测新方法。该方法将补偿后的A... 详细信息

在缺乏卫星过境时地面同步观测数据的情况下,大范围高时空分辨率的土壤水分监测存在一定的困难。针对这一问题,提出一种不依赖地面土壤水分同步观测数据的主、被动微波协同反演逐日高空间分辨率的土壤水分观测新方法。该方法将补偿后的AMSR-E土壤水分作为"高时间分辨率土壤水分观测控制值",以此计算逐日土壤水分变化量,并结合ASAR交替极化模式数据,反演高空间分辨率的土壤水分基准日期值,然后基于两者建立土壤水分协同反演模型。该模型适用于地势比较平坦、地表粗糙度较小且无植被覆盖或植被覆盖度较低的区域。在陕西省渭北台塬西部地区的试验结果表明:该方法参数拟合的决定系数约为0.81;反演得到的土壤水分与凤翔县农业气象站地面实测土壤湿度数据对比,两者的决定系数为0.92.土壤体积含水量的均方根误差为0.02.。反演结果可用于水分限制条件下作物生长模拟。

关键词：土壤水分 AMSR-E ASAR 作物生长模拟模型 AIEM

The mini-GWAC optical follow-up of gravitational wave alerts – results from the O2.campaign and prospects for the upcoming O3 run

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Research in Astronomy and Astrophysics 2020年第1期20卷 107-123页

作者： Damien Turpin Chao Wu Xu-Hui Han Li-Ping Xin Sarah Antier Nicolas Leroy Li Cao Hong-Bo Cai Bertrand Cordier Jin-Song Deng Wen-Long Dong Qi-Chen Feng Lei huang Lei Jia Alain Klotz Cyril Lachaud Hua-Li Li En-Wei Liang Shun-Fang Liu Xiao-Meng Lu Xian-Min Meng Yu-Lei Qiu Hui-Juan wang Jing wang Shen wang Xiang-Gao wang jian-Yan Wei Bo-Bing Wu Yu-Jie Xiao Da-Wei Xu Yang Xu Yuan-Gui Yang Pin-Pin Zhang Ruo-Song Zhang Shuang-Nan Zhang Ya-Tong ZhengandSi-Cheng Zou Key Laboratory of space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China LAL Univ.Paris-SudCNRS/IN2P3Universite Paris-SaclayF-91898 OrsayFrance APC Univ Paris DiderotCNRS/IN2P3CEA/lrfuObs de ParisSorbonne Paris CiteFrance CEA Saclay DRF/IRFU/Departement d’astrophysique91191 Gif-sur-YvetteFrance school of Astronomy and space Science University of Chinese Academy of SciencesBeijing 101408China Universite de Toulouse IRAP 14 Av.Edouard BelinF-31000 ToulouseFrance Institut de Recherche en Astrophysique et Planetologie(IRAP) UPS-OMPToulouseFrance Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China school of Physics and Electronic Information Huaibei Normal UniversityHuaibei 235000China

The second(O2.observational campaign of gravitational waves(GWs)organized by the LIGO/Virgo Collaborations has led to several breakthroughs such as the detection of GW signals from merger systems involving black holes or neutrons *** O2.14 GW alerts were sent to the astronomical community with sky regions mostly covering over hundreds of square *** them,six were finally confirmed as real astrophysical *** 2.13,a new set of ground-based robotic telescopes called Ground-based Wide Angle Camera system(GWAC)project and its pathfinder mini-GWAC has been developed to contribute to the various challenges of multi-messenger and time domain *** GWAC system is built up in the framework of the ground-segment system of the SVOM mission that will be devoted to the study of the multi-wavelength transient sky in the next *** O2.only the mini-GWAC telescope network was fully *** to the wide field of view and fast automatic follow-up capabilities of the mini-GWAC telescopes,they were adept to efficiently cover the sky localization areas of GW event *** this paper,we present the mini-GWAC pipeline we have set up to respond to GW alerts and we report our optical follow-up observations of eight GW alerts detected during the O2.*** observations provided the largest coverage of the GW localization areas with a short latency made by any optical *** found tens of optical transient candidates in our images,but none of those could be securely associated with any confirmed black hole-black hole merger *** on this first experience and the near future technical improvements of our network system,we will be more competitive in detecting the optical counterparts from some GW events that will be identified during the upcoming O3 run,especially those emerging from binary neutron star mergers.

关键词： gravitational waves methods:data analysis methods:observational (stars:)gammaray burst:general