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961.
Abstract Crack-filling clays and weathered cracks were observed in the Disaster Prevention Research Institute, Kyoto University (DPRI) 1800 m cores drilled from the Nojima Fault Zone, which was activated during the 1995 Hyogo-ken Nanbu earthquake (Kobe earthquake). The crack-filling clays consist mainly of unconsolidated fine-grained materials that fill opening cracks with no shear textures. Most of the cracks observed in the DPRI 1800 m cores are yellow-brown to brown in color due to weathering. Powder X-ray diffraction analyses show that the crack-filling clays are composed mainly of clay minerals and carbonates such as siderite and calcite. Given that the top of the borehole is approximately 45 m above sea level, most of the core is far below the stable groundwater table. Hence, it is suggested that the crack-filling clays and weathered cracks in the cores taken at depths of 1800 m were formed by the flow of surface water down to the deep fractured zone of the Nojima Fault Zone during seismic faulting.  相似文献   
962.
963.
The Mössbauer spectra of natural megacrystal clinopyroxene are usually fitted by 4 sets of symmetric doublets, A‐A', B‐B', C‐C' and D‐D', respectively, in terms of increasing Qs value in literature. But the assignments of those doublets are quite different, except the D‐D' doublet assigned to Fe3+at the lattice site M***1 in previous papers. Particularly, the assignment and interpretation of the C‐C' doublet are diverse. The oxidation experiments of natural megacrystal clinopyroxene collected from the Hannuoba basalt, North China, were performed under controlled conditions of temperature at 1000°C and oxygen fugacity of FMQ buffer in 1, 2, ***3 and 5 days respectively. The oxidized samples were then measured by X‐ray diffraction spectrometry and Mössbauer spectrometry. The oxidation of clinopyroxene is characterized by Fe2+ → Fe3+at M1 under the subsolidus conditions, which is consistent with the increase of the area of the D‐D' doublet when the heating time increases. Accordingly, the area of the A‐A' and B‐B' doublets decreases with the increasing heating time. However, the area of C‐C' keeps almost constant. Therefore, the 4 sets of doublets can be assigned correctly as follows: A‐A' doublet to Fe+2at M1, B‐B' Fe2+at M1, C‐C' Fe2+at M2, and D‐D' Fe3+at M1. The M1 site splitting is due to the NNN (Next Nearest Neighbour) effect of the M2 site. The amount of Fe3+at the tetrohedral site of megacrystal clinopyroxene is negligible according to this study.  相似文献   
964.
INTRODUCTIONLaserablationinductivelycoupledplasmamassspectrome tryisanincreasinglydevelopedanalyticaltechniqueforsolidsampleanalysis.LA ICP MSoffersattractivecharacteristicsofhighsensitivity ,lowdetectionlimits,minimalsampleprepara tion ,lessoxidesinterfe…  相似文献   
965.
lNTRODUCTIONThe theories and applications of structural contr()l tlcveloped rapidly in the last 20 years. As one of the additiona1 I)asslve control technologY' TMD is used in practice and can suppress the vibration caused by wind or machinery shake (Ayorinde and Warburton, 1980; Den Hartog, l956 ). The TMDsystem has been used in the industrial and civil buildlngs t() rc-duce structural vibration in some European and American ()o[lntries (Ayorinde and Warburton, l980; Warburton. ] f)…  相似文献   
966.
本文利用南京北郊164米气象塔实测资料对一次非降水弱冷锋过程的边界层风场结构一三维风速、横锋向水平散度、湍流通量和能量的时空分布,以及多尺度时空分布进行了计算分析。结果表明,在冷暖空气的过渡区(锋区)风场各参量具有明显的梯度,锋区前线的强上升气流与强冷锋相近,但锋区宽度较强冷锋宽得多,其时间尺度为30分钟,水平距离为35公里。锋面过境对风温场的影响时段为24小时,在这期间,出现阵风浪涌和多种中、小尺度(时间尺度为3-4小时、1-20分钟)的湍涡活动。  相似文献   
967.
青藏高原地表反照率计算研究   总被引:13,自引:1,他引:13  
根据改进的甚高分辨率扫描辐射仪(AVHRR)5个观测波段的光谱特征,经多次试验,设计了一组从卫星观测的地-气系统的辐射测值中提取晴空资料的多通道门槛值判识法和提取月平均反照率的合成法;并对1992年NOAA-12卫星获取的AVHRR资料进行计算处理,分析提取晴空数据,在此基础上按卫星轨道覆盖周期合成计算得到的晴空行星反照率和地表反照率,并且计算了逐月的地表反照率。对计算结果做了初步分析和认真比较。  相似文献   
968.
THE FOUNDATION AND MOVEMENT OF TROPICAL SEMI-GEOSTROPHIC ADAPTATION   总被引:4,自引:0,他引:4       下载免费PDF全文
The breakdown and foundation of geostrophic balance is one of the important movements inthe mid-and high-latitude atmosphere and oceans.In the tropical area,the value of Coriolis pa-rameter is so small that it is difficult to satisfy the bi-geostrophic equilibrium between the pressureand velocity fields.However,in the tropical area,the zonal velocity of some motions in the atmo-sphere and oceans is large,so the Coriolis force is not small,geostrophic balance can exist in zonaldirection,i.e.semi-geostrophic balance.Furthermore,in the dominant area of Hadley circulationin the atmosphere or the area near the ocean meridional boundary,the meridional velocity is large,so geostrophic balance can also exist in meridional direction.In this paper,the process of the dis-persion of inertial gravity wave and the foundation of semi-geostrophic balance are first discussed.Second,the adjustment process between the velocity and pressure fields after adaptation is alsoviewed,and the scale criterion of the semi-geostrophic adaptation is discussed,i.e.for the motionwith meridional scale greater than the equatorial Rossby radius of deformation,the velocity andpressure fields after adaptation change to fit the initial pressure field;on the contrary,the fieldschange to fit the initial zonal velocity field,and the strength of the fields after adaptation dependson the zonal scale.  相似文献   
969.
航空遥感影像中道路的半自动提取   总被引:1,自引:0,他引:1  
为了达到各种信息融合的目的,针对不同的情况,提出了多种信息约束下的道路提取方法。为了对提出的方法进行检验,给出了航空影像中不同类型的道路提取的例子  相似文献   
970.
高分辨区域输送模式中不同输送格式的对比试验   总被引:3,自引:0,他引:3  
本文对两种输送格式在理论试验的基础上,引入19层高分辨区域输送模式EM3,由中尺度模式(MM4)提供实例输送风场,积分至13、18、30、50、70小时,作分析和对比数值试验。采用的两种格式是:二阶动量矩守恒的Prather格式(以下简称为SOM)及通量订正的Smolar格式。数值试验结果表明,高精度的SOM格式使数值扩散减小一个量级, 使输送物质(SO#-[2])中心浓度比Smolar格式增大3~4倍, 采用SOM格式还明显改进了浓度中心水平平均运动轨迹的模拟精度,选择高精度的平流格式是改进模拟结果的重要途径。  相似文献   
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