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排序方式: 共有221条查询结果,搜索用时 31 毫秒
101.
102.
Internal structure of Longmenshan fault zone at Hongkou outcrop,Sichuan,China,that caused the 2008 Wenchuan earthquake 总被引:6,自引:1,他引:5
This paper reports the internal structures of the Beichuan fault zone of Longmenshan fault system that caused the 2008 Wenchuan earthquake,at an outcrop in Hongkou,Sichuan province,China.Present work is a part of comprehensive project of Institute of Geology,China Earthquake Administration,trying to understand deformation processes in Longmenshan fault zones and eventually to reproduce Wenchuan earthquake by modeling based on measured mechanical and transport properties.Outcrop studies could be integrate... 相似文献
103.
为了深入了解国际上新一代CO2等温室气体的空间观测计划及进展情况,以日本和美国于2009年最新发射的温室气体测卫星"呼吸"号(GOSAT)、"轨道碳观测者"(OCO)为例,分析了观测计划的开展情况,对卫星上搭载的传感器设置做了分析,对新一代温室气体专用观测卫星与传统卫星上的传感器做了对比,得出了新一代的传感器在设置上的特点:波段设置在近红外太阳辐射以获得边界层的温室气体含量,具有高的光谱分辨率以保证观测精度,多种观测方式结合以获得最大的信息量。并提出了我国应对温室气体观测资料缺乏的对策,发展专用观测卫星或传感器,以提供我们自己的高精度的全球和区域温室气体观测数据。 相似文献
104.
����GPS���ݷ������ձ���������ɱ���齻�紦��Ӧ����Ƚ� 总被引:1,自引:0,他引:1
??????????????????????????GPS???????????(1997-01~1999-12)??????Hori???????????????????齻????????????????????????????:????????????С??????????????????????????????7 cm/a??50%?????????????10~30 km??????????????????齻??????????????Yabuki-Matu??ura????????????????????????????Hori???????????б?????????????????????????????????????????????????в?????????Ч????????????????????????????????Hori????????????????????????????????????????????????????????????????????????? 相似文献
105.
山西霍山山脉河流地貌定量参数及其构造意义 总被引:2,自引:0,他引:2
河流地貌形态定量研究是了解构造活动与地表过程耦合作用的重要途径之一.霍山山脉位于山西地堑系中部,介于临汾盆地和太原盆地之间,以发育霍山山前断裂带和1303年洪洞Ms8级地震而著名,通过分析跨断裂带及周边的48条河流的纵剖面形态、SL参数、Hack剖面、面积高程积分曲线以及HI值等,得到以下认识:1)跨断裂带的河流,其纵剖面在断层两侧的形态具明显差异,反映其受断层活动控制,而其他河流,除极少部分在上游存在局部陡变外,纵剖面为近似下凹的指数曲线形态显示近均衡状态;2)河流的HI值及积分曲线显示了霍山地区新生代以来整体处于强抬升弱侵蚀状态,即所有河流均处于壮年或幼年期;3)48条河流一致上凸的Hack剖面也表明霍山地区新生代以来处于强烈的构造抬升阶段,跨断裂带的Hack剖面形态以陡变下降而区别与其他河流的近似圆弧形;4)跨断裂带河流的SL/K参数在断层附近出现异常高值,反映了SL/K参数与断层垂直差异运动的相关性,周边其他河流的SL/K参数反映了没有差异运动的准均衡状态,局部的异常高值可能对应不同基岩的抗风化能力差异.河流地貌定量参数与构造环境存在显著的相关性,河流地貌定量参数特征揭示霍山山前断裂带在新生代以来的强烈垂向运动特征. 相似文献
106.
以甘孜-玉树断裂带东南段的地质地貌为研究对象,在遥感解译的基础上,通过对典型地区的详细野外调查和探槽研究对该段晚第四纪活动性进行研究。在断裂沿线的生康乡、仁果乡、错阿乡、日阿乡进行了断错地貌分析和晚第四纪滑动速率计算, 生康区的水平滑动速率为(7.6±0.5)mm/a, 垂直滑动速率为(1.1±0.1)mm/a; 仁果区的水平滑动速率为(8.0±0.3)mm/a,垂直滑动速率为(1.1±0.1)mm/a; 错阿区的水平滑动速率为(10.3±0.4)mm/a; 日阿区的水平滑动速率为(10.8±0.8)mm/a, 垂直滑动速率为(1.1±0.1)mm/a。在仁果乡和错阿乡进行了探槽研究,两处探槽都揭示了多次古地震事件,虽然揭露的断层构造样式有所不同,但总体上都是以走滑为主兼有一定的逆冲分量。综合古地震事件和滑动速率分析表明,甘孜-玉树断裂带东南段晚第四纪尤其是全新世以来活动剧烈。 相似文献
107.
Internal structure of Longmenshan fault zone at Hongkou outcrop,Sichuan, China,that caused the 2008 Wenchuan earthquake
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This paper reports the internal structures of the Beichuan fault zone of Longmenshan fault system that caused the 2008 Wenchuan earthquake, at an outcrop in Hongkou, Sichuan province, China. Present work is a part of comprehensive project of Institute of Geology, China Earthquake Administration, trying to understand deformation processes in Longmenshan fault zones and eventually to reproduce Wenchuan earthquake by modeling based on measured mechanical and transport properties. Outcrop studies could be integrated with those performed on samples recovered from fault zone drilling, during the Wenchuan Earthquake Fault Scientific Drilling (WFSD) Project, to understand along-fault and depth variation of fault zone properties. The hanging wall side of the fault zone consists of weakly-foliated, clayey fault gouge of about 1 m in width and of several fault breccia zones of 30–40 m in total width. We could not find any pseudotachylite at this outcrop. Displacement during the Wenchuan earthquake is highly localized within the fault gouge layer along narrower slipping-zones of about 10 to 20 mm in width. This is an important constraint for analyzing thermal pressurization, an important dynamic weakening mechanism of faults. Overlapping patterns of striations on slickenside surface suggest that seismic slip at a given time occurred in even narrower zone of a few to several millimeters, so that localization of deformation must have occurred within a slipping zone during coseismic fault motion. Fault breccia zones are bounded by thin black gouge layers containing amorphous carbon. Fault gouge contains illite and chlorite minerals, but not smectite. Clayey fault gouge next to coseismic slipping zone also contains amorphous carbon and small amounts of graphite. The structural observations and mineralogical data obtained from outcrop exposures of the fault zone of the Wenchuan earthquake can be compared with those obtained from the WFSD-1 and WFSD-2 boreholes, which have been drilled very close to the Hongkou outcrop. The presence of carbon and graphite, observed next to the slipping-zone, may affect the mechanical properties of the fault and also provide useful information about coseismic chemical changes. 相似文献
108.
1981-2010年中国散射光合有效辐射的估算及时空特征分析 总被引:1,自引:0,他引:1
光合有效辐射(Photosynthetically active radiation,PAR)是植物光合作用的主要能量来源,其散射组分能够增强植被冠层光能利用率,从而增加碳吸收。因此,散射PAR是生态系统生产力模型的重要驱动因子。本文尝试估算我国1981-2010 年的散射PAR,通过空间化得到近30 年月尺度10 km分辨率的散射PAR空间数据集,并分析了其空间分布特征和时间变化趋势。结果表明:(1)1981-2010 年散射PAR多年平均值的空间分布具有明显的空间异质性,总体上东北部较低,南部和西部较高。全国范围内的多年平均值在6.66~15.27 mol m-2 d-1之间,且夏季散射PAR最大,冬季最小。(2)1981-2010 年全国所有像素散射PAR年平均值表现出明显的上升趋势,上升幅度为0.03 mol m-2 d-1/10a;但前10 年下降趋势明显,且1982、1983、1991 和1992 年存在明显异常。春季的散射PAR呈现微弱的下降趋势,其他季节均呈上升趋势。(3)1981-2010 年散射PAR时间变化率的空间分布具有明显的季节变化和区域差异,我国大体呈现南部区域上升,北部区域下降。 相似文献
109.
Geochemical Characteristics and LA-ICP-MS Zircon U-Pb Dating of Amphibolites in the Songshugou Ophiolite in the Eastern Qinling 总被引:3,自引:0,他引:3
LIU Liang CHEN Danling ZHANG An ZHANG Chengli YUAN Honglin LUO Jinhai The Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi''an Shaanxi 《《地质学报》英文版》2004,78(1):137-145
Geochemical studies on the arnphibolites in the Songshugou ophiolite from Shangnan County, Shaanxi Province demonstrate that the protolith of the amphibolites is tholeiitic. The arnphibolites can be classified into two groups according to their REE patterns and trace element features. Rocks of the first group are depleted in LREE while rocks of the second group are slightly depleted in LREE or flat from LREE to HREE without significant Eu anomaly. The first group of rocks have (La/Yb)N=0.33-0.55, (La/Sm)N= 0.45-0.65, and their La/Nb, Ce/Zr, Zr/Nb, Zr/Y and Ti/Y ratios are averaged at 1.20, 0.12, 31.02, 2.92 and 198, respectively, close to those of typical N-MORB. The second group of rocks have (La/Yb)N=0.63-0.95, (La/ Sm)N = 0.69--0.90, and their average La/Nb, Ce/Zr, Zr/Nb, Zr/Y and Ti/Y ratios are 0.82, 0.83, 1.15, 0.16, 19.00, 2.58 and 225, respectively, which lie between those of typical N-MORB and E-MORB but closer to the former. The two groups of rocks both exhibit flat patterns from Th to Yb in th 相似文献
110.
ZHAI Yusheng DENG Jun TANG Zhongli XIAO Rongge SONG Honglin PENG Runmin SUN Zhongshi WANG Jianping Key Laboratory of Lithospheric Tectonics Lithoprobing Technology China University ofGeosciences Ministry of Education Beijing Bureau of Exploration Development of Geology Mineral Resources of Gansu Province Lanzhou Gansu Jilin University Changchun Jilin 《《地质学报》英文版》2004,78(2):592-603
The North China Craton (NCC) is one of the largest blocks composing the continent. Different types of continental margins well developed around the NCC, along with lots of metallogenic systems of different metals and different times. Based on the study on the structural evolution of the NCC, the authors made a new division of tectonic units of the NCC. Through an analysis of the data of 1:25000 geochemical survey on stream sediments, regional geochemical features of main ore-forming elements including Au, Ag, Cu, Pb, Zn, W, Ni, Co and Mo of the NCC are discussed in the paper. Then different metallogenic systems and their forming processes and geodynamics are discussed in detail. At last, temporal and spatial distribution regularities are summarized and ten favorable ore-control factors on the paleocontinental margins are put forward, including (1) abundance of ore sources; (2) rendezvous of ore-forming fluids; (3) high thermo-dynamic anomaly; (4) remarkable Earth crust-mantle interaction; (5) cluster of 相似文献