Tectono-thermal modeling of the Yinggehai Basin,South China Sea

Based on the observed data, the average value of surface heat flow in the Yinggehai Basin is calculated and it turns out to be 84.1 mW/m². The thermal evolution of the basin since the Cenozoic era has been attempted by tectono-thermal modeling. Three-phase extension made the basin become hotter and hotter, reaching its climax in paleo-temperature history since 5.2 Ma. And nowadays, the basin is in the heat flow decreasing period. During the Cenozoic era, the basement heat flow remained at 50–70 mW/m² all the time. This is related to the degree of each extension phase, stretching rate mode and also the limited basin scale. Modeling results also show that, the surface heat flow is controlled mainly by the basement heat flow, and less than 20% comes from radiogenic heat production in the sediments of the basin     

长江流域降水变化及其趋势演变

本文对中国长江流域降水趋势进行了分析.指出对月降水量而言,20世纪后50年不同区域出现1不胃的降水趋势变化特征.趋势插补法研究表明中国降水时空分布趋势十分明显.对长江流域长期降水资料分析研究指出夏季月份降水时间更集中,而对年降水而言在一些站则表现出明显的周期变化.     

美国城市搜索与救援体系的组成及运作模式概述

美国城市搜索与救援体系是世界上最完善的体系之一，多年来在城市救灾和应对突发事件中发挥了重要作用，减轻了生命和财产的损失。文章概述了美国城市搜索与救援体系的组成、任务、运作原则和管理机构及支援机构。     

平极长期漂移与地球平均下地幔黏性估计

利用9个国际纬度观测站的平纬长期变化序列,重新讨论并估计了平极的长期漂移,得到漂移的平均速率为(3.356“±0.142”)×l0-3/a,方向为西经78.7°±2.5°.进一步基于最新的ICE-4G冰期后地壳反弹模型,采用地球上8个冰盖的冰融参数,估计了理论的平极长期漂移方向为西经74.8°.由观测的平极长期漂移速率为约束,基于1066B地球模型,估计得到地球平均下地幔的黏性为vLM=(0.5-1.7)×1022Pa^.s,表明vLM应具有近1022Pa^.s量级,并认为地球平极的长期漂移很可能是由最近的21000年以来冰期后的地壳反弹所致.     

大姚地热动态特征分析

通过大姚高精度水温观测井水地质、井孔条件的分析，震例观测资料、实验观测数据的处理，以及井水水质分析结果，表明大姚水温周期性变化的突出位置是井深75m左右，根本原因是该地层石膏脉稳定释热，含水层热水与井内冷水混合过程中，在通道内形成钙盐类沉淀物（如CaSO4CaCO3），堵塞对流通道，含水层内外压差突破被阻塞通道，热水反复侵入井内，便形成水温周期性变化。地震的孕育、发生和调整过程，由于应力场作用，产生附加地热场，水温基值发生变化，周期畸变或消失，这种附加地热动态是可以恢复的。所以认为大姚地热动态是井区特殊地层地热信息的反映。     

武定6.5级地震孕震过程测震学特征

研究了1995年10月24日云南省武定6．5级强震前的地震活动性参数、空间分布图象、距震中135km的巧家台振幅比、波速比演化特征，结果表明武定6．5级地震孕育发生有明显的阶段性变化，经历了早期（1988年4月－1992年7月），中期（1992年8月－1995年3月），晚期（1995年4月－1995年10月）阶段的发展，最终发生了强震。最后应用岩石破裂实验结果，分析了武定6．5级地震孕震过程。     

The topographic imprint of a transient climate episode: the western Andean flank between 15·5° and 41·5°S

Mountain‐range topography is determined by the complex interplay between tectonics and climate. However, often it is not clear to what extent climate forces topographic evolution and how past climatic episodes are reflected in present‐day relief. The Andes are a tectonically active mountain belt encompassing various climatic zones with pronounced differences in rainfall, erosion, and glacier extent under similar plate‐boundary conditions. In the central to south‐western Andes, climatic zones range from hyperarid desert with mean annual rainfall of 5 mm/a (22·5°S) to year‐round humidity with 2500 mm/a (40°S). The Andes thus provide a unique setting for investigating the relationship between tectonics, climate, and topography. We present an analysis of 120 catchments along the western Andean watersheds between 15·5° and 41·5°S, which is based on SRTMV3‐90m data and new medium‐resolution rainfall, tropical rainfall measurement mission (TRMM) dataset. For each basin, we extracted geometry, relief, and climate parameters to test whether Andean topography shows a climatic imprint and to analyze how climate influences relief. Our data document that elevation and relief decrease with increasing rainfall and descending snowline elevation. Furthermore, we show that local relief reaches high values of 750 m in a zone between 28°S to 35°S. During Pleistocene glacial stages this region was affected by the northward shifting southern hemisphere Westerlies, which provided moisture for valley‐glacier formation and extended glacial coverage as well as glacial erosion. In contrast, the southern regions between 35°S to 40°S receive higher rainfall and have a lower local relief of 200 m, probably related to an increased drainage density. We distinguish two different, climatically‐controlled mechanisms shaping topography: (1) fluvial erosion by prolonged channel‐hillslope coupling, which smoothes relief, and (2) erosion by valley glaciers that generates relief. Finally, Our results suggests that the catchment‐scale relief of the Andes between 28°S to 35°S is characterized by a pronounced transient component reflecting past climatic conditions. Copyright © 2010 John Wiley & Sons, Ltd.     

Assessment of extreme drought and human interference on baseflow of the Yangtze River

Attention has been given to baseflow in large rivers, but up to now, no study on baseflow for the Yangtze River in combination with extreme drought and extensive human activities has been carried out. Discharge data in 2000–2005 and in the extreme drought years, 1978 and 2006, at stations along the main stream, lakes and distributaries of the Yangtze River were collected to analyse the features of baseflow in 2006 by using baseflow separation technique, HYSEP. It can be seen that the baseflow relative to the streamflow in 2006 was greater than those in other years. The variation of baseflow discharge in the Upper Yangtze River Stream (UYRS) was larger than that in the Mid‐Lower Yangtze River Stream (MLYRS). Human activities in MLYRS are more intensive than that in the UYRS and the baseflow discharge was greater. The baseflow is influenced by the extreme climate and human activities along the Yangtze River with the former being the dominant factor in 2006. The contribution of human interference to baseflow discharge was about 10% in 2006. Copyright © 2009 John Wiley & Sons, Ltd.     

层间隔震技术在地铁车辆段大平台上部土地开发上的应用研究

为开发北京地铁八王坟车辆段大平台上部空间,层间隔震技术被采用。通过非线性时程分析和模拟地震动振动台试验,研究了此层间隔震结构体系的抗震性能。研究结果表明采用隔震技术后,结构体系抗震性能得到很大提高,其地震响应满足规范要求。     

等幅侧向位移循环下柱混凝土纤维应变规律的试验研究

在已完成的包括16个构件的等位移循环加载钢筋混凝土柱的系列试验中，通过在其中3根柱的塑性铰区沿混凝土受力方向安设位移计，较准确测定了混凝土测试标距内的平均应变在一个加载循环内的变化规律及其随周数增长的变化规律；发现了单周最大压应变随周数的增长而持续增大，单周最大名义拉应变随周数增长而持续减小的重要现象；并与柱顶水平力-水平位移滞回规律实测结果相对应，结合截面受力特征对所得单周和多周应变变化规律的成因作了分析。