扁铲侧胀试验判别液化的研究和实践

通过对扁铲侧胀试验判别液化的研究和实践，提出了在上海地区采用扁铲侧胀试验判别液化的公式，扁铲侧胀试验判别液化与标准贯入和静力触探试验判别液化的方法对比，具有相对较好的结果，是一种有前途的液化判别方法。     

灰色系统在地面沉降分析中的应用

该文将灰色系统理论引入地面沉降的研究之中。根据上海地面沉降的历史数据建立了上海地面沉降发展的GM(1,1)模型以及地面沉降与地下水位变化的映射GM(1,2)模型,最后运用所建立的模型对地面沉降的发展态势进行了预测。     

灾害预报与鸡西煤矿瓦斯爆炸事件

2002年上半年,伴随着厄尔尼诺现象的日益加剧,全球性重大自然灾害频繁发生.6月20日发生在中国黑龙江省鸡西煤矿的瓦斯爆炸事件和6月22日发生在伊朗的强烈地震,时间恰逢月亮近地潮的6月19日和太阳潮半日形变最大值的夏至的6月21日附近,是地球形变和排气较强烈的时段.据国内外有关资料,月球与地球发震有关系的重要条件是“近地点兼朔、望”以及各大行星特定位置的配合,张元东称之为“特殊天象组合期”[1];郭增建等提出,月亮赤纬角或太阳黄赤交角最大时地球形变和排气最强烈[2～5].在此期间,中国各种大的突发性灾难,如空难、海难、火车事故、矿…     

中国东北样带NDVI的季节变化及其与气候因子的关系

NDVI是研究大尺度生态学问题一个非常有用的指数,它可以为估价全球植被动态模型提供足够的信息.中国东北样带是全球变化研究中首选样带之一,本文分析了分辨率为1km×1km的NDVI年内季节变化的两个特征值:年均NDVI(NDVI-I)和NDVI年内极差(NDVI-MM)在样带内5种不同植被类型间的变化及其与年平均气温和降水量之间的相关关系.结果表明,NDVI具有明显的季节变化格局,NDVI-I和NDVI-MM由东到西均呈下降趋势,NDVI-I与降水量具有显著的线性回归关系,降水量能够解释NDVI-I和NDVI-MM空间变异的绝大部分.这一结果说明NDVI反映了植被沿环境梯度的时空变化格局,可用于监测样带植被对气候变化的响应.     

Petrography and uplift history of the Quaternary Takidani Granodiorite: could it have hosted a supercritical (HDR) geothermal reservoir?

The Quaternary Takidani Granodiorite (Japan Alps) is analogous to the type of deep-seated (3–5 km deep) intrusive-hosted fracture network system that might support (supercritical) hot dry/wet rock (HDR/HWR) energy extraction. The I-type Takidani Granodiorite comprises: porphyritic granodiorite, porphyritic granite, biotite-hornblende granodiorite, hornblende-biotite granodiorite, biotite-hornblende granite and biotite granite facies; the intrusion has a reverse chemical zonation, characterized by >70 wt% SiO₂ at its inferred margin and <67 wt% SiO₂ at the core. Fluid inclusion evidence indicates that fractured Takidani Granodiorite at one time hosted a liquid-dominated, convective hydrothermal system, with <380°C, low-salinity reservoir fluids at hydrostatic (mesothermal) pressure conditions. ‘Healed’ microfractures also trapped >600°C, hypersaline (35 wt% NaCl_eq) fluids of magmatic origin, with inferred minimum pressures of formation being 600–750 bar, which corresponds to fluid entrapment at 2.4–3.0 km depth. Al-in-hornblende geobarometry indicates that hornblende crystallization occurred at about 1.45 Ma (7.7–9.4 km depth) in the (marginal) eastern Takidani Granodiorite, but later (at 1.25 Ma) and shallower (6.5–7.0 km) near the core of the intrusion. The average rate of uplift across the Takidani Granodiorite from the time of hornblende crystallization has been 5.1–5.9 mm/yr (although uplift was about 7.5 mm/yr prior to 1.2 Ma), which is faster than average uplift rates in the Japan Alps (3 mm/yr during the last 2 million years). A temperature–depth–time window, when the Takidani Granodiorite had potential to host an HDR system, would have been when the internal temperature of the intrusive was cooling from 500°C to 400°C. Taking into account the initial (7.5 mm/yr) rate of uplift and effects of erosion, an optimal temperature–time–depth window is proposed: for 500°C at 1.54–1.57 Ma and 5.2±0.9 km (drilling) depth; and 400°C at 1.36–1.38 Ma and 3.3±0.8 km (drilling) depth, which is within the capabilities of modern drilling technologies, and similar to measured temperature–depth profiles in other active hydrothermal systems (e.g. at Kakkonda, Japan).     

Seismic risk assessments and GIS technology: applications to infrastructures in the Friuli–Venezia Giulia region (NE Italy)

This paper illustrates the seismic risk preliminary estimates of two different groups of structures located on the territory of the Friuli–Venezia Giulia region (NE Italy) : the first group includes some special industrial plants, and the second group includes bridges and tunnels belonging to the regional highway network. The part of the study on special industrial plants tries to evaluate the degree of expected damage, taking into account their structural typology and ground shaking expressed in terms of macroseismic intensity. The second part of the study is an application of the HAZUS methodology to the tunnels and bridges of a highway network: the combination of expected ground shaking and the construction characteristics lead to very different risk levels, especially when considering the bridges. The resulting damage levels to bridges and tunnels are still only indicative because of the fragility curves used in the evaluations: they were developed for existing bridge and tunnel structural typologies in the U.S.A. Moreover, both examples show the power of GIS technology in storing, elaborating, and mapping spatial data. Copyright © 2003 John Wiley & Sons, Ltd.     

Lithology and palynology of Neogene sediments on the narrow edge of the Kitakami Massif (basement rocks), northeast Japan: Significant change for depositional environments as a result of plate tectonics

Abstract A controversial stratigraphic section, the Taneichi Formation, is exposed along the Pacific Coast of northeastern Honshu, the main island of the Japanese Archipelago. Although most sediments of the formation have long been dated as late Cretaceous, the northern section of it has been assigned to (i) the Upper Cretaceous; (ii) the Paleogene; or (iii) the Neogene. In the present report, we present the data of palynological and sedimentological studies, showing that the northern section should be assigned to the Neogene. A more important point in the present study is that we invoke some basic principles of fluvial sedimentology to resolve this stratigraphic subject. The lignite layers full of Paleogene–Miocene dinoflagellate cysts and pollen assemblages drape over the boulder‐sized (>40 cm in diameter) clasts in the northern section. However, the layers totally consist of aggregates of small lignite chips, indicating that the lignites are allochthonous materials. The mega‐clasts with derived microfossils in the lignites are thought to have been deposited as Neogene fluvial (flood) sediments in the newly formed Japanese Archipelago. Prior to the Miocene, the northern Honshu was part of the Eurasian Plate, thus the boulder‐sized clasts cannot be envisaged as long river flood deposits along the continental Paleogene Pacific Coast. Instead, the mega‐clasts with the draping lignites were probably derived from nearby Miocene highlands in the newly born island arc.     

A procedure for evaluating seismic energy demand of framed structures

Energy serves as an alternative index to response quantities like force or displacement to include the duration‐related seismic damage effect. A procedure to evaluate the absorbed energy in a multistorey frame from energy spectra was developed. For low‐ to medium‐rise frames, it required a static pushover analysis of the structure to determine the modal yield force and ductility factor of an equivalent single‐degree‐of‐freedom system for the first two modes. The energy spectra were then used to determine the energy contribution of each mode. A procedure was also developed to distribute the energy along the frame height based on energy shapes. This study showed that the second‐mode response in some cases needs to be considered to reflect the energy (or damage) concentration in the upper floors. Copyright © 2002 John Wiley & Sons, Ltd.     

时间谱电阻率法中的剩余电磁效应研究

根据频谱激电（SIP）法或复电阻率（CR）法中研究剩余电磁（REM）效应的思想，通过分析时间谱电阻率（TSR）法中场的基本特征，在TSR法中建立了与SIP（或CR）法中参数Φmax/Φ0max相类似的参数－Emax/E0，用来描述了TSR法中的REM效应。通过对一维可极化大地模型的REM效应的理论计算，验证了用Emax/E0表示的REM异常可用来形象地反映地电断面电阻率的高低。     

TRMM PR雷达与阜阳雷达降水资料的对比研究

选取了1998年与1999年HUBEX观测资料，将TRMM卫星上的星载降雨雷达PR与阜阳的713数字化天气雷达资料在以下3个方面做了比较：(1)强度场的分布；(2)平均反射率廓线；(3)灵敏度。分析、比较结果可知阜阳雷达在探测灵敏度和水平方向的分辨率要高于PR，但由于波束宽度、衰减和资料转化过程计算误差的原因，其远距离处的观测值与真实值有一定偏差。PR波长短，对衰减敏感，尤其是在垂直方向上经过强衰减后，订正值仍偏小。但由于探测方式的不同PR在水平方向上不存在衰减的问题，且其资料分布均匀，因此提出一种用PR资料来订正地基雷达资料的方法用以提高地基雷达探测的精确度。