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柴北缘超高压变质带沙柳河蛇绿岩型地幔橄榄岩及其意义

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岩石学报 2005年第4期21卷 1049-1058页

作者：张贵宾宋述光张立飞牛耀龄舒桂明教育部造山带与地壳演化重点实验室 department of earth sciences University of DurhamDurham DH1 3LEUK

本文报道了柴北缘大陆型超高压变质带沙柳河地区发现的蛇绿岩型地幔橄榄岩,其原始矿物组合为橄榄石+斜方辉石+铬铁矿。方辉橄榄岩中识别出两个世代的橄榄石,第一世代橄榄石(OI^1)残晶发育扭折带,化学成分与现代大洋地幔橄榄岩的橄榄石一... 详细信息

本文报道了柴北缘大陆型超高压变质带沙柳河地区发现的蛇绿岩型地幔橄榄岩,其原始矿物组合为橄榄石+斜方辉石+铬铁矿。方辉橄榄岩中识别出两个世代的橄榄石,第一世代橄榄石(OI^1)残晶发育扭折带,化学成分与现代大洋地幔橄榄岩的橄榄石一致,第二世代橄榄石(OI^2)Fo 值高达94～97,其内部含有细小的流体包裹体,是第一世代橄榄石蛇纹石化后再次变质的产物。斜方辉石残晶的成分具有高 Al 和 Ca 的特征,与大洋地幔橄榄岩中斜方辉石的成分一致。温压条件的估算反映该橄榄岩体属于典型的尖晶石相方辉橄榄岩。其围岩是由堆晶辉长岩变质的条带状蓝晶石榴辉岩,二者构成了大洋蛇绿岩套的下部层位,并且与区内具有 N-MORB 和 OIB 性质的榴辉岩共生。这些特征表明该方辉橄榄岩应代表洋壳下伏地幔橄榄岩,从而揭示大陆造山带从早期的大洋俯冲消亡到大陆俯冲碰撞的完整过程。

关键词：地幔橄榄岩蛇绿岩大陆型超高压变质带:柴北缘

Experimental studies of interaction between water and albite melts

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Science China earth sciences 2002年第11期45卷 999-1007页

作者：孙樯谢鸿森郑海飞郭捷丁东业 department of Geology Peking University Beijing China Institute of Geochemistry Chinese Academy of Sciences Guiyang China

On the basis of FTIR and Raman spectra studies on hydrous albite glasses, it is found that there exist two water solubility mechanisms in albite melts simultaneously. On the one hand, water interacts with Al -O°-Al to produce the Q3 Al-OH, leading to depolymerization, and this results in the appearance of 4500 cm(1 in FTIR spectra and 900 cm(1 in Raman spectra. On the other hand, the exchange of H+ in water with Na+ in albite melt as charge-balancing cation occurs at the same time. In the initial stage, the production of Al -OH is the dominant solubility mechanism, at the stage of higher water contents, the exchange of H+ with Na+ becomes the important dissolution mechanism. The dissolution of water into albite melt can be expressed as H2O+ 3NaAlSi3O8 = 2NaAl(OH)Si3O7.5 +HAlSi3O8 +NaOH.

关键词： water, albite glasses, solubility mechanism.

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唐海-商都地震台阵剖面下方岩石圈结构

地球物理学报 2013年第11期56卷 3828-3836页

作者：王兴臣丁志峰朱露培中国地震局地球物理研究所北京100081 department of earth and Atmos. sciences Saint Louis Univ. MO 63108 USA

2006年10月到2009年9月，中国地震局地球物理研究所在华北地区布设了250个流动地震台站，本文选取其中一条从唐海经过唐山、三河、北京、张家口到商都的宽频带地震台阵剖面作为研究对象．利用该剖面49个宽频带台站记录的191个远震数据... 详细信息

2006年10月到2009年9月，中国地震局地球物理研究所在华北地区布设了250个流动地震台站，本文选取其中一条从唐海经过唐山、三河、北京、张家口到商都的宽频带地震台阵剖面作为研究对象．利用该剖面49个宽频带台站记录的191个远震数据进行了S波接收函数的计算，通过共转换点叠加成像对剖面下方的岩石圈结构进行研究，获得了剖面下方的岩石圈精细结构．Moho界面和岩石圈一软流圈界面清晰可见，剖面下方地壳厚度从西到东逐渐减薄，从42km逐渐减薄至30km左右，西部陆块岩石圈厚度从100km逐渐减薄至70km，中部和东部陆块岩石圈厚度变化相对平稳，介于60-80km，表明剖面下方岩石圈遭受了大规模的明显减薄．结合其他地球物理方法研究结果，我们认为剖面下方华北克拉通东部陆块岩石圈减薄主要是由于热侵蚀作用引起的．

关键词： S波接收函数华北克拉通岩石圈结构

Poly-and perfluoroalkyl substances(PFASs)in sediment samples from Roodeplaat and Hartbeespoort Dams,South Africa

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Emerging Contaminants 2020年第1期6卷 367-375页

作者： Bulelwa Batayi Jonathan O.Okonkwo Peter A.Daso Cornelius C.Rimayi department of Environmental Water and Earth SciencesFaculty of ScienceTshwane University of TechnologyArcadia CampusPretoria0001South Africa department of Water and Sanitation Resource Quality Information Services(RQIS)RoodeplaatP.Bag X3130001PretoriaSouth Africa

This study aimed at determining PFAS concentrations in sediments obtained from two important water systems in South Africa,namely,the Roodeplaat and Hartbeespoort *** samples were collected in March and June representing summer and winter *** analytes were extracted using the half-dry alkaline method followed by solid phase extraction and analysed with liquid chromatography-tandem mass *** mean PFASs concentrations in Roodeplaat Dam(0.14 e89.04 ng g^-1)were significantly higher(p=0.016)than in Hartbeespoort Dam(0.03e31.37 ng g^-1).Perfluoro-n-decane sulfonic acid(PFDS),perfluoro-n-heptyl sulfonate(PFHpS),perfluoro-n-nonane sulfonic acid(PFNS)and perfluoro-n-octane sulfonic acid(PFOS)were the most dominant PFASs *** were observed to be generally higher in summer compared to winter,however,the difference is statistically insignificant(p=0.659).The perfluorosulfonic acids(PFSAs)was more dominant than the perfluorocarboxylic compounds,suggesting possible preferential usage of PFSAs in this *** findings were different from reports from China and Korea,which reported long chain perfluorinated carboxylic acids(PFCAs)in sediments as the dominant *** results also revealed that the PFAS concentrations found in the present study were higher than the concentrations found in China,Germany,and Ethiopia but lower than the concentrations detected in the Western Cape Province in South Africa.

关键词： PFASs Concentrations Sediments Hartbeespoort and roodeplaat dams South Africa

Development of a modified thermal humidity index and its application to human thermal comfort of urban vegetation patches

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ecosystem Health and Sustainability 2022年第1期8卷 242-259页

作者： Xiaorou Zheng Na Zhang Xin Wang College of Resources and Environment University of Chinese Academy of SciencesBeijingChina Center for Geo-spatial Information Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenChina Beijing Yanshan earth Critical Zone National Research Station University of Chinese Academy of SciencesBeijingChina Beidou Research Institute South China Normal UniversityFoshanChina

Extremely hot environments can trigger serious health *** evaluate the effects of microclimate on thermal comfort,we proposed and validated a modified thermal humidity index(MTHI)that combined air temperature and relative humidity with land surface temperature(LST).MTHI was more sensitive to microclimate changes than the general thermal humidity index that includes only T and RH,and thus the thermal comfort could be better *** an urban riparian buffer study,we estimated the temporal dynamics and spatial distribution of MTHI values for 47 vegetation patches and explored how structural characteristics of patches affect the thermal *** results showed that planting could significantly reduce LST and *** patches with complex vertical structures had considerably higher thermal comfort than those with simple *** nearest distance to river or increasing plant abundance could reduce the thermal *** were significant differences in the structure characteristics between the patches with MTHI70,implying the critical thresholds of variations in thermal comfort with patch *** that people always feel uncomfortable during the daytime in July,optimizing the patch structure is essential to improve the microclimate regulation services of an urban landscape.

关键词： Land surface temperature nearest distance to river vertical vegetation structure vegetation coverage tree canopy density adjacent patch index

Deforestation in Latin America in the 2000s predominantly occurred outside of typical mature forests

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The Innovation 2024年第3期5卷 88-98页

作者： Zhiyu Zhang Wenjian Ni Shaun Quegan Jingming Chen Peng Gong Luiz Carlos Estraviz Rodriguez Huadong Guo Jiancheng Shi Liangyun Liu Zengyuan Li Yating He Qinhuo Liu Yosio Shimabukuro Guoqing Sun Key Laboratory of Remote Sensing and Digital earth Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Shijingshan DistrictBeijing 100049China Chinal of Mathematics and Statistics University of SheffieldSheffield S37RHUK department of Geography and Program in Planning University of TorontoTorontoON M5S 3G3Canada department of earth sciences and department of Geography University of Hong KongHong KongChina Forest Science department Luiz de Queiroz College of AgricultureUniversity of São PauloAv.Pádua Dias11Piracicaba 13418-900Brazil National Space Science Center Chinese Academy of SciencesBeijing 100190China Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing 100091China Research Institute of Forest Policy and Information Chinese Academy of ForestryBeijing 100091China Remote Sensing department National Institute for Space Research(INPE)Av.dos Astronautas 1758São Josédos Campos 12227-010Brazil department of Geographical sciences University of MarylandCollege ParkMD 20742USA

The role of tropical forests in the global carbon budget remains controversial,as carbon emissions from deforestation are highly *** high uncertainty arises from the use of either fixed forest carbon stock density or maps generated from satellite-based optical reflectance with limited sensitivity to biomass to generate accurate estimates of emissions from *** space missions aiming to accurately map the carbon stock density rely on direct measurements of the spatial structures of forests using lidar and *** found that lost forests are special cases,and their spatial structures can be directly measured by combining archived data acquired before and after deforestation by space missions principally aimed at measuring ***,using biomass mapping,we obtained new estimates of carbon loss from deforestation ahead of forthcoming space ***,using a high-resolution map of forest loss and the synergy of radar and lidar to estimate the aboveground biomass density of forests,we found that deforestation in the 2000s in Latin America,one of the severely deforested regions,mainly occurred in forests with a significantly lower carbon stock density than typical mature forests.

关键词： forest Latin lidar

Tectonic Implications and Petrogenesis of the Various Types of Magmatic Rocks from the Zedang Area in Southern Tibet

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Journal of earth Science 2019年第6期30卷 1125-1143页

作者： Yuanku Mengc Fahui Xiong Jingsui Yang Zhao Liu Kieran AIles Paul TRobinson Xiangzhen Xu Shandong Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdao 266590China Center for Advanced Research on the Mantle(CARMA) Key Laboratory of Deep-Earth Dynamics of Ministry of Natural ResourcesInstitute of GeologyChinese Academy of Geological SciencesBeijing 100037China Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China department of Geosciences and Geography University of HelsinkiHelsinki 00014Finland

In this study,we report systematically field observations,geochronology,whole-rock geochemistry and Sr-Nd-Hf isotopic dataset on the various types of magmatic rocks collected from the Zedang ***,the diabase and gabbro have a low-K calc-alkaline affinity,whereas the basalt and plagiogranite have medium to high-K calc-alkaline *** addition,the basalts are highly enriched in light rare earth elements(LREE)and large ion lithophile elements(LILE),but strongly depleted in high strength field elements(HFSE),indicating that their magma source probably was derived from a subduction-or arc-related *** contrast,both the gabbro and diabase mainly demonstrate an N-MORB-like affinity consistent with normal mid-oceanic ridge basalt(N-MORB)*** zircon U-Pb dating results suggest that the basalts were crystallized earlier at ca.158–161 Ma(Oxfordian stage),but the gabbro was crystallized at ca.131 Ma(Hauterivian stage of Early Cretaceous).The zircon U-Pb dating results correspond with the field observations that the veins of gabbro intruded ***,the plagiogranite has a weighted mean age of ca.160 Ma(MSWD=2.1)consistent with the basalt within the *** basalt and the plagiogranite have significantly positiveεHf(t)values(+5.8 to+15.6 and+8.6 to+16.1,respectively),suggesting that they were originated from partial melting of a depleted ***,basalt and plagiogranite are characterized by the wide variations ofεHf(t)values indicating minor amounts of exotic crustal material input during the later magma ***,the basalt shows duplex geochemical features of island-arc and mid-oceanic ridge basalt,corresponding to the supra-subduction zone-(SSZ)type *** sum up,two distinct magmatic events identified in this study probably suggest an intra-oceanic arc system existing in the Zedang area during the Late Jurassic,but the intra-oceanic arc subduction extinguished in the Early Cretaceous as suggested b

关键词： geochronology petrogenesis magmatic rocks Zedang sub-terrane tectonic implications

Integrating global land cover products for improved forest cover characterization: an application in North America

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International Journal of Digital earth 2014年第9期7卷 709-724页

作者： Xiao-Peng Song Chengquan Huang Min Feng Joseph O.Sexton Saurabh Channan John R.Townshend Global Land Cover Facility Department of Geographical SciencesUniversity of MarylandCollege ParkMDUSA

Six widely used coarse-resolution global land cover data-sets–Global Land Cover Characterization(GLCC),Global Land Cover 2000(GLC2000),GlobCover land cover product(GlobCover),MODIS land cover product(MODIS LC),the University of Maryland land cover product(UMD LC),and the MODIS Vegetation Continuous Fields tree cover layer(MODIS VCF)disagree substantially in their estimates of forest *** a regression tree model trained on higher-resolution,Landsat-based data,these multisource multiresolution maps were integrated for an improved characterization of forest cover over North *** using a withheld test sample,the integrated percent forest cover(IPFC)data-set has a root mean square error of 11.75%–substantially better than the 17.37% of GLCC,17.61% of GLC2000,17.96% of GlobCover,15.23% of MODIS LC,19.25%of MODIS VCF,and 15.15%of UMD LC,*** demonstrated for forest,this approach based on integration of multiple products has potential for improved characterization of other land cover types as well.

关键词： land cover forest data fusion regression tree North America

Global hybrid simulations of soft X-ray emissions in the earth’s magnetosheath

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earth and Planetary Physics 2024年第1期8卷 47-58页

作者： Jin Guo TianRan Sun San Lu QuanMing Lu Yu Lin XueYi Wang Chi Wang RongSheng Wang Kai Huang School of earth and Space sciences University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology/CAS Key Lab of Geospace Environment University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China National Space Science Center Chinese Academy of SciencesBeijing 100190China Physics department Auburn UniversityAuburnALUSA

earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the *** X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a *** performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic *** all cases,magnetic reconnection occurs at low latitude *** soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the *** X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray ***,the magnetopause boundary can be identified using multiple viewing *** also find that solar wind conditions have little effect on the magnetopause *** Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered.

关键词： magnetopause X-ray emissivity X-ray imaging SMILE global hybrid-PIC simulation