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101.
Defiled Cities     
Edward Said laid some of the foundation stones for postcolonialism, but this project has — for the most part — ignored the pressing question of Palestine that has been the goad for so much of Said's own work. This essay discusses some of the ways in which, in the wake of September 11, the Israeli government of Ariel Sharon took advantage of the so-called "war on terrorism" to ratchet up the dispossession of the Palestinian people. It also seeks to show that imaginative geographies are never merely representations — they are also performances of space — and that, in this case (as in others), they have served to rationalise and radicalise colonial aggression, ultimately through the prosecution of a necropolitics.  相似文献   
102.
根据大柳矿井11采区上覆岩层的实际情况,采用概率积分法对煤层开采后的地表变形情况进行了预测,绘制了地表下沉等值线图,分析了地表沉陷对周围环境的影响程度和范围,并提出了防治措施,为区内开展类似研究工作和大柳矿井未来生产沉陷的防治提供了参考依据。  相似文献   
103.
甘肃临夏黄土剖面:15万年环境演变的良好记录   总被引:13,自引:1,他引:13  
康建成  李吉均 《地质论评》1993,39(2):165-175
历经15万年的甘肃临夏北塬黄土剖面,沉积速率大、古土壤序列完整。特别是在距今14—8万年的末次间冰期形成的三层古土壤,末次冰期间冰段形成的数层弱成土型古土壤,其特征优于其它黄土剖面。对北塬剖面磁化率、孢粉、粒度、地球化学特征的综合研究表明,该剖面完整地记录了15万年以来的环境变化,为检验以往从大陆冰盖和深海沉积中得出的环境变化模式提供了途径。  相似文献   
104.
梁灵君  杨忠山  刘超 《水文》2012,(1):39-42,28
以北京城市化发展区凉水河大红门闸控制流域为典型区域,在分析区域20世纪80年代到2000年后下垫面变化特征的基础上,结合区域同时期的降水和径流资料,采用MIKE11软件中的UR-BAN模块构建流域降雨径流模型,以流域模拟流量和实测流量拟合效果最佳为原则,利于多场次的实测降水进行降雨径流的模拟分析,研究区域城市化发展对水文特性变化的影响。  相似文献   
105.
The Mugla province is one of the major marble producing regions located in the southern flank of the Menderes Massif in SW Turkey. The Menderes Massif is a regionally metamorphosed massif with an old Pan-African core and cover successions from the Permo–Carboniferous to Paleocene. There are four major metamorphic carbonate horizons in the cover successions exploited for the marble production. These horizons are located within the Permo–Carboniferous, Triassic, Upper Cretaceous and Paleocene successions along the southern flank of the Menderes Massif. Here the world wide known marbles with names such as the Mugla Black, the Milas White, Veined, Pearl, Aubergine, Lilac and Lemony, the Mugla White and the Aegean Bordeaux are found.

Detailed geological studies were carried out in selected marble quarries representing the different stratigraphic levels to determine the geological parameters affecting the marble production in the southern flank of the Menderes Massif in SW Turkey. The geological parameters such as bedding, joints, schist interlayers and mica filled joints affecting the block production from the marble beds are considered to be primary features. The presence of dolomite bands and lenses, abnormal sized calcite crystals and emery minerals which affect the slab and the production qualities and appearances are considered to be secondary geological parameters. The primary and secondary geological parameters affecting the marble productions at different stratigraphical levels in SW Turkey, are determined and the practical aspects of these findings are discussed.  相似文献   

106.
目的 研究了由多种卫星磁场观测数据建立的最新的世界地磁场模型WMM2010与地面台站观测值之间的关系,并将常用的国际参考地磁场模型IGRF11作为对比参照。首先分析了IGRF11与台站观测值的对比关系,验证了IGRF模型的精度和可靠性。其次分析了 WMM2010与IGRF11模型的差异,引入绝对误差、均方根误差、相对误差和权重系数等指标来进行评价,分析表明,WMM2010模型在研究地磁异常场时的正常场改正和改善边界效应时填补空白区域中更具参考价值。  相似文献   
107.
通过对帕克菲尔德历史地震数据的分析,发现该地存在有11年及11年的倍数周期,美国学者发现的22年周期只是其中一个特例。分析认为,无论是使用11年周期还是22年周期,均无法准确预测出2004年帕克菲尔德地震,因此美国学者的预测未能成功。原因在于出现了一个新的黄金分割规律,即11年×0.618=6.8年,使用该规律可以准确预测出2004年地震。依据以上发现的3个规律,尝试预测下一次帕克菲尔德地震可能发生在2032年附近,建议综合使用当地观测数据分析以缩小误差。  相似文献   
108.
辉煌的五年     
从矿产勘查、基础地质、地质科技、公益性地质工作等方面汇整安徽省"十一五"地质工作主要成果,指出了制约地质找矿突破存在的主要问题,总结了安徽省地质工作的主要做法。  相似文献   
109.
ABSTRACT

The temporal dynamics of groundwater–surface water interaction under the impacts of various water abstraction scenarios are presented for hydraulic fracturing in a shale gas and oil play area (23 984.9 km2), Alberta, Canada, using the MIKE-SHE and MIKE-11 models. Water-use data for hydraulic fracturing were obtained for 433 wells drilled in the study area in 2013 and 2014. Modelling results indicate that water abstraction for hydraulic fracturing has very small (<0.35%) negative impacts on mean monthly and annual river and groundwater levels and stream and groundwater flows in the study area, and small (1–4.17%) negative impacts on environmental flows near the water abstraction location during low-flow periods. The impacts on environmental flow depend on the amount of water abstraction and the daily flow over time at a specific river cross-section. The results also indicate a very small (<0.35%) positive impact on mean monthly and annual groundwater contributions to streamflow because of the large study area. The results provide useful information for planning long-term seasonal and annual water abstractions from the river and groundwater for hydraulic fracturing in a large study area.  相似文献   
110.
The ecological condition and biodiversity values of floodplain wetlands are highly dependent on the hydrological connectivity of wetlands to adjacent rivers. This paper describes a method for quantifying connectivity between floodplain wetlands and the main rivers in a wet tropical catchment of northern Australia. We used a one‐dimensional hydrodynamic model to simulate time‐varying water depths across the stream network (i.e. rivers, streams and man‐made drains). The timing and duration of connectivity of seven wetlands (four natural and three artificial) with the two main rivers in the catchment were then calculated for different hydrological conditions. Location and areal extent of the wetlands and the stream network were identified using high‐resolution laser altimetry, and these data formed key inputs to the hydrodynamic model. The model was calibrated using measured water depths and discharges across the floodplain. An algorithm was developed to identify contiguous water bodies at daily time steps, and this gave the temporal history of connection and disconnection between wetlands and the rivers. Simulation results show that connectivity of individual wetlands to both rivers varies from 26 to 365 days during an average hydrological condition. Location, especially proximity to a main river, and wetland type (natural stream or artificial drain) were identified as key factors influencing these levels of connectivity. Some natural wetlands maintain connection with the river for most or all of the year, whereas the connectivity of some artificial wetlands varies from 26 to 36 days according to their patterns of network connection to adjacent rivers – a result that has important implications for the accessibility of these types of wetland to aquatic biota. Using readily available river gauge data, we also show how connectivity modelling can be used to identify periods when connectivity has fallen below critical thresholds for fish movement. These connectivity patterns within the floodplain network are central to the setting of river flows that will meet environmental requirements for biota that use floodplain wetlands during their life history. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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