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951.
利用1999—2007和2007—2009年GPS资料,采用块体变形模型和GPS速度剖面研究了川滇地区的分阶段变形特征,结果显示川西北-滇中-滇西南块体主压应变率方向由北向南呈顺时针方向旋转;安宁河断裂、则木河断裂存在剪切应变积累,小江断裂南段以走滑为主、北段以应变积累为主;汶川地震对丽江-小金河断裂中南段、安宁河断裂和金沙江断裂有一定影响,对则木河断裂、小江断裂和红河断裂的影响较小。 相似文献
952.
һ�ֵ�Ӧ�������Լ��鷽�� 总被引:1,自引:0,他引:1
?????????????????????????????????????÷???????????????????GPS???λ??????????????????????????????????????????????????????????????????????????Щ?????????????????γ?????????????? 相似文献
953.
广义位势理论为岩土材料的本构关系研究指出了更开阔的数学背景。基于广义位势理论可以构造出基于应力空间的模型,也可构造出基于应变空间的模型,利用两者之间的对称关系,把常规基于应力空间的模型直接转换到应变空间中,对本构模型自身无需做任何改动。基于广义位势理论也可以对已有的本构模型进行修正,比如,可基于广义位势理论对剑桥模型进行修正,这种修正可使模型利用三轴试验的部分成果,比单纯使用压缩试验的成果要好一些。另外,也初步探讨了模型的三维化问题。 相似文献
954.
基于实体建模的三维地层构造 总被引:2,自引:1,他引:1
以三维实体模型为基础,提出了三维地层实体模型,给出了三维实体地层模型的体系数据结构和几何拓扑结构,完整描述了三维地层模型。给出了地层模型的构造过程,并讨论了地层缺失、倒转等的特殊地质状况的构模处理方法。三维地层实体模型是完整,全面的地层模型,比基于多层网格和三棱柱体元的地层模型具有更多的优点。 相似文献
955.
956.
D. Bocchiola C. Mihalcea G. Diolaiuti B. Mosconi C. Smiraglia R. Rosso 《Advances in water resources》2010
We develop a simple model to evaluate the daily flow discharges in the ablation season for the 11 km2 Pantano basin in the Retiche Italian Alps, based upon the data gathered during a three years field campaign. The Pantano basin embeds the Venerocolo debris covered and the Avio debris free glaciers, covering 2.14 km2 in the Adamello Group, where the widest Italian glacier Adamello is located. First, degree-day models based upon air temperature are tuned to calculate snow and ice melt at daily scale. Glaciers’ meteorological data are collected from an automatic weather station (AWS), operating on the glacier during summer 2007. The melt factors in the debris covered areas of the glacier are estimated against debris thickness, using a data driven parameterization. The flow discharge from the catchment is estimated using semi distributed flow routing for the ablation seasons of four years, from 2006 to 2009. The predicted discharges are compared to those derived from inverse reservoir's routing at the Benedetto lake, catching the basin outflow. The proposed approach is valuable as a tool to investigate the hydrology of poorly gauged glacierized areas, including those with debris covered ice, widely diffused and yet poorly understood. Pending accurate parameterization the approach is usable for water resources evaluation and for long term assessment of the climate change impact on the glacierized areas within the Alps. 相似文献
957.
A correct understanding of the hydrodynamics and morphodynamics of tidal basins is of fundamental importance for the fate of the Venice Lagoon, Italy. If on one hand, the development of sophisticated numerical models is called for in order to reproduce the complexity of the mechanisms governing the morphodynamic evolution of many natural environments, including lagoons, on the other hand, a clear knowledge of the reliability and limits of the results provided by these models is crucial in order to establish the condition under which they can be safely applied. To this aim, researchers involved in numerical modeling in the framework of the recent Corila research programmes, agreed to perform an accurate comparison of results provided by three different numerical models, applying them to the test case offered by the experimental investigations performed under controlled conditions by Tambroni et al. (2005a). Here, we consider the following numerical models: (i) a 2D finite element hydrodynamic model coupled with a 2D finite volume morphodynamic model (5 and 3); (ii) a 2D finite element morphodynamic model (Ferrarin et al., 2008); (iii) a 2D depth-averaged model for the inlet region, coupled with a 1D model for the channel (Tambroni et al., 2005b). A first set of simulations concerns the fixed bed case and shows that all the models provide similar results: in particular, they are able to predict the observed free surface oscillations satisfactorily, while comparison with the measured velocity field is less satisfactory. Moreover, as far as the flow field at the inlet is concerned, the models describe accurately the potential flow into the channel during the flood phase, while they are not able to adequately reproduce the occurrence of the fine structure of the shear layers shed by the inlet edges during the ebb phase. This limit is related to the shallow water character of the models. As for the morphodynamics, the long term equilibrium configurations of the bottom of the channel and of the near inlet region show qualitative agreement with the experimental observations, although in this case the differences between the results provided by the distinct numerical approaches are more marked. 相似文献
958.
在岩石板上切割出多条切缝并以石膏填充,将其分为3个构造特征区:A区(断层交汇区)、B区(左行左列岩桥区)、C区(右行左列岩桥区)。采用双轴加压、定点应变、声发射信息系统和实时全息干涉计量方法(激光)进行观测研究。结果表明:在岩样破坏孕育过程中,各个特征区都出现了特大破裂。每个特大破裂发生前定点应变、激光干涉条纹图(应变场)和声发射信息都出现了特征变化。特大破裂的发生有先后,其前兆特征的出现也有先后,并且各区有各自的特点,某些前兆还可能在各区之间交替出现。研究认为,三个区的断层结构性质不同,这就导致了不同的破裂顺序,甚至产生不同的前兆现象。 相似文献
959.
960.