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Dynamic response of mountain tunnel,bridge,and embankment along the Sichuan-Tibet transportation corridor to active fault based on model tests

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Journal of Mountain Science 2024年第1期21卷 182-199页

作者： HUANG Beixiu QIAO Sijia chen Xulei LI lihui QI Shengwen Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation academy for Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China

The Sichuan-Tibet transportation corridor is prone to numerous active faults and frequent strong *** extensive studies have individually explored the effect of active faults and strong earthquakes on different engineering structures,their combined effect remains *** research employed multiple physical model tests to investigate the dynamic response of various engineering structures,including tunnels,bridges,and embankments,under the simultaneous influence of cumulative earthquakes and stick-slip misalignment of an active *** prototype selected for this study was the Kanding No.2.tunnel,which crosses the Yunongxi fault zone within the Sichuan-Tibet transportation *** results demonstrated that the tunnel,bridge,and embankment exhibited amplification in response to the input seismic wave,with the amplification effect gradually decreasing as the input peak ground acceleration(PGA)*** PGAs of different engineering structures were weakened by the fault rupture ***,the misalignment of the active fault may decrease the overall stiffness of the engineering structure,leading to more severe damage,with a small contribution from seismic ***,the seismic vibration effect might be enlarged with the height of the engineering structure,and the tunnel is supposed to have a smaller PGA and lower dynamic earth pressure compared to bridges and embankments in strong earthquake zones crossing active *** findings contribute valuable insights for evaluating the dynamic response of various engineering structures crossing an active fault and provide an experimental reference for secure engineering design in the challenging conditions of the Sichuan-Tibet transportation corridor.

关键词： Dynamic response Engineering structure Sichuan-Tibet transportation corridor Active fault Earthquake Model test

A 2.8 Ma record of environmental evolution and tectoni events inferred from the Cuoe core in the middle of Tibetan Plateau

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Science china Earth sciences 2004年第11期47卷 1025-1034页

作者： SHEN Ji1,Lü Houyuan2.WANG Sumin1,chen Shiyue1,YANG Xiangdong1,WU Yanhong1 & ZHU Zhaoyu3 1.Nanjing institute of Geography and Limnology,{2.,Nanjing 2.0008,china 2.institute of geology and geophysics,{2.,Beijing 10002.,china 3.Guangzhou institute of Geochemistry,{2.,Guangzhou 510640,china correspondence {12. be addressed to Shen Ji(email: jishen@***)

Based on a multi-proxy investigation into the deep core of the Cuoe Lake in the middle of Tibetan Plateau, a 2.8 Ma paleoclimatic and paleoenvironmental evolution is recon- structed. The result of magnetic stratum indicates that the lake basin was formed at about 2.8 MaBP, while the multi-proxy analyses of lithology, grain size, magnetic susceptibility and geo- chemical elements reveal that there have been three major environmental evolution stages and at least two intensive uplifts of the Tibetan Plateau in the lake basin area, i.e. during 2.8—2.5 MaBP, the lake basin came into being as a result of the disaggregation of the planation surface and rapid rising of the Tibetan Plateau. During 2.5—0.8 MaBP, with gradual uplift of the Tibetan Plateau, the environment of this area was more effectively controlled by the climatic cycle of the alternative glacial-interglacial stages. After 0.8 MaBP, the middle part of the Plateau accelerated its uplift and entered cryoshere.

关键词： Tibetan Plateau, 2.8 MaBP, environmental evolution, tectonic events, Cuoe Lake.

Mars exploration——In situ K-Ar dating of jarosite

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Science china Earth sciences 2024年第3期67卷 641-656页

作者： Jing YANG Dewen ZHENG Ying WU Hong chen Li YANG Bin ZHANG Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesInstitute of GeomechanicsChinese Academy of Geological SciencesBeijing 100081China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China institute of Earth sciences China University of GeosciencesBeijing 100083China Key Laboratory of Cenozoic geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029Chin

To accurately determine the chronological framework of climatic variations recorded by various Martian terrains, the absolute ages of Martian events and cratering rate need to be constrained by either in situ dating or returned samples. In situ K-Ar dating is currently a more plausible dating technique as compared with sample return. Jarosite(KFe_(3)[SO_(4)]_(2.[OH]_(6)) is the only confirmed K sulfate mineral that is widely present on Mars, as indicated by in situ detection, orbital remote sensing, and meteorite studies. Jarosite can be used for precise K-Ar and (40)Ar/(39)Ar dating. The preservation of jarosite on Mars provides information about the nature and duration of aqueous processes on the Martian surface. Different ages of Martian jarosite represent the key to constraining the transition from Martian surface water activity to arid climatic conditions. This paper summarizes recent advances in our knowledge of the spatial distribution of Martian jarosite, its mineralogical properties and stability on Mars, the Ar diffusion kinetics of jarosite, and the current status of in situ K-Ar dating. Moreover, we examine the key scientific issues to be addressed for in situ K-Ar dating of jarosite and Martian sample return missions, and discuss future research directions.

关键词： Mars Jarosite In situ K-Ar dating Ar diffusion Stability

Melt-Lithosphere Interaction Controlled Compositional Variations in Mafic Dikes from Fujian Province,Southeastern china

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Journal of Earth Science 2021年第6期32卷 1445-1453页

作者： Zhuliang Lei Gang Zeng Jianqiang Liu Xiaojun Wang lihui chen Xiaoyu Zhang Jinhua Shi State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing210023China institute of Marine geology College of OceanographyHohai UniversityNanjing210098China

Late Mesozoic magmatism in southeastern china has been widely considered to be related to the subduction of the Paleo-Pacific ***,it remains controversial whether mafic rocks are derived from the lithosphere or the *** we present a comprehensive study on mafic dikes from Fujian Province in southeastern china,aiming to understand their *** types of mafic rocks have been recognized based on their trace-element ***-Ⅰrocks show arc-like trace-elemental characteristics,while type-Ⅱrocks are distinguished by their relatively flat patterns in primitive-mantle-normalized trace-element *** such differences between two types of rocks,these mafic dikes show two trends in the plots of^(87)Sr/^(86)Sr(i)versus La/Nb,which can be explained by the influences of crustal contamination and melt-lithospheric mantle interaction,respectively.^(87)Sr/^(86)Sr(i),La/Nb,Sr/Y and Zr/Y ratios of type-I rocks are significantly correlated to the thickness of the underlying lithosphere,and the signals of lithosphere are clearer with increasing lithospheric *** highlights the important influences of melt-lithosphere interaction during their *** observations also indicate that these mafic rocks are more likely to have been originated from the asthenosphere rather than the lithospheric mantle.

关键词： mafic dike lithospheric mantle asthenosphere melt-lithosphere interaction southeastern china

山西隰县岭上地区白云岩矿地质特征及成因探讨

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地质找矿论丛 2024年第2期39卷 186-191页

作者：韩效斌弓晨王勇郎学聪李沛龙游立辉中国冶金地质总局第三地质勘查院太原030032

白云岩是冶炼金属镁的一种重要矿产资源。本文以赋存于上寒武统—下奥陶统三山子组中的山西隰县岭上地区白云岩矿为研究对象,通过对区域地质背景、矿区地质、矿体地质、矿石质量等特征的总结,提出了本区白云岩矿的找矿标志、岭上白云岩... 详细信息

白云岩是冶炼金属镁的一种重要矿产资源。本文以赋存于上寒武统—下奥陶统三山子组中的山西隰县岭上地区白云岩矿为研究对象,通过对区域地质背景、矿区地质、矿体地质、矿石质量等特征的总结,提出了本区白云岩矿的找矿标志、岭上白云岩矿床成因——岭上白云岩矿床为沉积型浅海相沉积型准同生+准同生后白云岩的组合成因矿床;三山子组一段(∈_(3)s^(1))层位,可作为山西隰县黄土镇岭上一带白云岩矿的找矿标志。

关键词：冶镁白云岩白云岩矿地质特征矿床成因岭上地区隰县山西省

SnO_(2.添加剂对AgCuOIn_(2.O_(3)复合材料电接触性能的影响

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复合材料学报 2022年第3期39卷 1322-1331页

作者：胡晨周晓龙陈力刘满门王立惠昆明理工大学云南省新材料制备与加工重点实验室云南昆明650093 稀贵金属综合利用新技术国家重点实验室云南昆明650106 中国有色桂林矿产地质研究院有限公司桂林市微电子元件电极材料与生物纳米材料重点实验室广西桂林541004

采用反应合成法结合塑性变形工艺制备了不同SnO_(2.含量的AgCuOIn_(2.O_(3)SnO_(2.电触头材料,在JF04C触点材料测试机上对不同SnO_(2.含量的电触头材料进行电接触实验,研究了该材料的接触电阻、抗熔焊性和材料转移特性,并通过扫描电镜... 详细信息

采用反应合成法结合塑性变形工艺制备了不同SnO_(2.含量的AgCuOIn_(2.O_(3)SnO_(2.电触头材料,在JF04C触点材料测试机上对不同SnO_(2.含量的电触头材料进行电接触实验,研究了该材料的接触电阻、抗熔焊性和材料转移特性,并通过扫描电镜对试样阴/阳表面电侵蚀下的微观形貌进行了分析。结果表明AgCuOIn_(2.O_(3)SnO_(2.触头材料接触电阻小,当测试电压不超过12.V时,接触电阻随测试次数的增加呈现缓慢下降最后趋于稳定的趋势,当电压增大到18 V时,各试样的接触电阻均增大,且增幅程度不一。对于SnO_(2.含量不变的试样,熔焊力随着测试次数的增加呈现先增大后减小的趋势,材料的燃弧能量随电压的增大而增大,随着测试次数的增加呈锯齿形波动。电接触过程材料主要为阴极转移,材料的损耗量随SnO_(2.量的增多先增大后减小,阴/阳极触头表面呈凸凹状,且表面存在熔融金属液凝固状花样,材料转移主要以熔桥方式进行,当SnO_(2.含量在0.5wt%~1.0wt%时,电接触性能最为优异。

关键词：反应合成法 AgCuOIn_(2.O_(3)SnO_(2.接触电阻抗熔焊性电触头材料塑性变形工艺

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电子探针分析技术进展及面临的挑战

岩石学报 2019年第1期35卷 261-274页

作者：张迪陈意毛骞苏斌贾丽辉郭顺中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 中国科学院青藏高原地球科学卓越创新中心北京100101

电子探针是研究地球与行星物质组成最基础的微束分析技术。近年来,固体地球科学和行星科学的不断发展,促使电子探针分析技术取得了一系列进展:矿物微量元素分析、稀土矿物测试方法完善、副矿物定年、富Fe矿物/熔体Fe^(3+)含量测定、场... 详细信息

电子探针是研究地球与行星物质组成最基础的微束分析技术。近年来,固体地球科学和行星科学的不断发展,促使电子探针分析技术取得了一系列进展:矿物微量元素分析、稀土矿物测试方法完善、副矿物定年、富Fe矿物/熔体Fe^(3+)含量测定、场发射电子探针及软X射线分析谱仪的开发及应用等。同时,电子探针分析技术也面临着诸多挑战:微量元素测试在降低检测限的同时,还需要提高分析的准确度和精确度;降低二次荧光效应的影响;场发射电子探针在低电压下需要建立全新的分析条件和校正方式。基于这些挑战,电子探针未来在微量元素监测标样开发、二次荧光效应校正、场发射电子探针及软X射线分析谱仪应用、波谱仪完善和微区多种分析技术集成等方面具有发展潜力,以便为地学样品的研究提供更丰富、更准确的微米尺度成分信息。

关键词：微量元素分析副矿物定年场发射电子探针软X射线分析谱仪二次荧光效应

SnO_(2.增强相对AgCuOIn_(2.O_(3)电触头材料显微组织与性能的影响

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稀有金属材料与工程 2022年第1期51卷 66-73页

作者：胡晨陈力张晓李金涛刘满门王丽慧周晓龙昆明理工大学材料科学与工程学院云南昆明650093 稀贵金属综合利用新技术国家重点实验室云南昆明650106 中国有色桂林矿产地质研究院有限公司桂林市微电子元件电极材料与生物纳米材料重点实验室广西桂林541004

采用反应合成法结合塑性变形工艺制备了不同SnO_(2.含量的AgCuOIn_(2.O_(3)SnO_(2.电触头材料,利用扫描电镜和金相显微镜表征了材料的微观形貌及显微组织,分析对比了不同SnO_(2.含量的材料金相组织及其增强相的分布均匀性,并利用X射线... 详细信息

采用反应合成法结合塑性变形工艺制备了不同SnO_(2.含量的AgCuOIn_(2.O_(3)SnO_(2.电触头材料,利用扫描电镜和金相显微镜表征了材料的微观形貌及显微组织,分析对比了不同SnO_(2.含量的材料金相组织及其增强相的分布均匀性,并利用X射线衍射分析了材料的物相结构。测量了材料的抗拉伸强度、硬度、电阻等性能。结果表明:添加适量的SnO_(2.能使组织中的孔隙尺寸缩小、其他缺陷明显减少。氧化物弥散分布在银基体中,极大地改善了AgCuOIn_(2.O_(3)电触头材料的显微组织均匀性。在SnO_(2.含量不变时,材料的电阻率随塑性变形程度增加而有所降低;随着SnO_(2.含量增多,电阻率呈现先降低后升高的趋势,最后趋于定值,约为2.4μΩ·cm。添加SnO_(2.后各试样材料的硬度均显著升高,SnO_(2.含量为1%(质量分数)的材料具有最优的抗拉伸强度和延伸率。

关键词：反应合成法 AgCuOIn_(2.O_(3)SnO_(2.显微组织性能

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2.2.年行星物理学热点回眸

科技导报 2024年第1期42卷 99-113页

作者：魏勇柴立晖陈一定范开高佳维何飞乐会军李国主林红磊綦超戎昭金宋玉环孙伟家王誉棋吴兆朋徐长仪闫丽梅尧中华袁憧憬乐新安张驰张辉张金海钟俊中国科学院地质与地球物理研究所北京100029 中国科学院大学地球与行星科学学院北京100049

2.2.年,行星物理学作为行星科学的一个主干分支学科,呈现出百花齐放、交相辉映的态势。中国的行星物理学还发展出一些新兴的领域,如太阳与行星磁场发电机过程、地球与行星空间环境长期变化、地球与行星多圈层耦合过程等,为中国未来深空... 详细信息

2.2.年,行星物理学作为行星科学的一个主干分支学科,呈现出百花齐放、交相辉映的态势。中国的行星物理学还发展出一些新兴的领域,如太阳与行星磁场发电机过程、地球与行星空间环境长期变化、地球与行星多圈层耦合过程等,为中国未来深空探测的跃升发展奠定了坚实基础。选择2.个行星物理研究领域,以中国行星物理学的进展和热点为主线,置之于世界和历史的时空横纵之中,展示了中国和世界行星物理学的发展态势。

关键词：深空探测行星科学行星物理学