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781.
The Canyon Range syncline, Central Utah, is composed of an alternating sequence of competent quartzite and incompetent argillite layers and is used here as a natural case study of multilayer folding processes. Geometric details of this fold are evaluated in terms of energy consumption in order to determine which kinematic components of folding are dominant at various stages of fold tightening. In addition, this paper attempts to evaluate what mechanism(s) (e.g. kink folding, fracture formation and sliding along surfaces) are involved in each kinematic component.In general, the patterns preserved in the Canyon Range syncline are comparable to multilayer folding models. In more detail, the following is concluded from this case study. (1) The competent and incompetent members deformed primarily by cataclastic flow and consumed approximately equal amounts of energy. (2) The roles of original competent and incompetent layers reversed during folding. (3) As the syncline tightened, less energy was consumed with increasing hinge fractions. (4) The least amount of energy was consumed with 40° limb dips (i.e., 100° interlimb angle). (5) With an open fold geometry (interlimb angle ≥140°), the hinge region consumed 70% of the fold's total energy. (6) Once the fold reached an interlimb angle of 60°, the limbs consume close to 70% of the total energy. (7) When the fold reached an interlimb angle of ≤60°, the incompetent layer(s) consumed 90% of the fold's energy. 相似文献
782.
783.
房屋全生命周期管理信息平台在一定程度上实现了房屋相关信息资源的共享,为相关部门的规划和决策提供了有效的支持和依据。时态GIS在房屋全生命周期管理信息平台中应用保证了房屋在任意时点的可追溯性,在房地产历史变化研究、房地产市场动态监控以及城市发展规划方面都具有重要的参考意义。 相似文献
784.
金纯 《测绘与空间地理信息》2012,(6):188-189,195
在城镇居民居住需求的多样化以及商品房价格持续上涨的背景下,商品房的设计出现了综合化的趋势,新的样式层出不穷,给房产测绘带来了很多基础性认定的问题。本文主要结合实际工作中遇到的房屋层高、特殊形式的复式楼梯、有柱走廊的认定等几个细节问题进行探讨,并提出了实际工作中的解决方法及一些建议。 相似文献
785.
Zaire Z. Dinzey‐Flores 《Singapore journal of tropical geography》2012,33(2):198-211
In 1992, Puerto Rico's governor and police superintendent incorporated the National Guard with local police in a militarized battle against crime. Mano dura contra el crimen (strong arm/iron fist against crime) policies led to the gating of 82 public housing communities in the island. Simultaneously, privileged private communities organized and petitioned municipalities to retrofit their neighbourhoods with gates in the name of safety. These enclosures followed the privatized management of all public housing communities in the island only a few years before. Based on ethnographic research, I examine the sociospatial outcomes of these policies, how they reframe community participation and deploy a discourse of self‐responsibility that distributes power unequally across private and public housing communities. While in the privileged communities these policies have cultivated community leaders and invigorated social life as residents take control over public space, the gates in the communities of the poor reflect a skeletal structure of democracy. Private management companies impose increasingly restrictive regulations in attempts to organize the community and the only recourse to participation is to engage in small acts of everyday resistance, from apathy to subversion. As part of larger neoliberal tendencies to retrench the ‘public’ in favour of the ‘private’, the mano dura policies curtail democracy as the voices of the poor are silenced and the scope of efficacy of the rich expands. 相似文献
786.
787.
2002年塔里木河流域"四源一干"地表径流情势 总被引:13,自引:9,他引:4
2002年塔河流域内平原及山区气温都明显偏高, 平原降水偏多, 山区降水略偏多.3~10月 0 ℃层高度接近常年.塔里木河4条源流出山口天然径流量273.9×108m3, 比多年平均值227.0×108m3多46.9×108m3, 偏多20.7%, 属丰水年.其中发源于天山山脉的阿克苏河和开都河-孔雀河径流增幅大, 水量充沛, 属丰水年; 而发源于喀喇昆仑山脉的叶尔羌河和源于西昆仑山的和田河径流量保持多年均值年.4条源流入塔里木河水量为54.82×108m3.在塔里木河干流上游段耗水量25.42×108m3, 是干流最大的耗水区段, 中游段耗水量24.55×108m3, 下游段耗水量7.38×108m3.上、中游区间耗水量49.97×108m3, 占阿拉尔站年径流量的90.8%.从7月20日至11月10日共计114 d由博斯腾湖向塔里木河下游生态应急输水, 从博斯腾湖调水12.67×108m3, 恰拉水库分水闸向塔里木河输水2.339×108m3, 大西海子水库下泄3.313×108m3, 年内台特玛湖形成了28.74 km2的水域面积, 下游沿河地下水位普遍回升, 影响范围达800 km2, 生态效益十分显著. 相似文献
788.
流域耗水平衡方法与应用 总被引:2,自引:1,他引:1
流域水量平衡分析是水资源现状评价与水资源合理调度研究工作中的-个核心.本文基于遥感技术估算的蒸散,结合监测统计数据,提出了流域耗水平衡方法,以海河流域为例进行了2002年-2007年流域及子流域的耗水平衡分析,流域多年平均蓄变量为-62.3亿m3,其中农业生产是流域水资源消耗的主要因素,占耗水总量的54.3%,年际变动范围较小(-5%-8%).通过流域蓄变量变化和流域蒸散结构的分析,揭示海河流域存在的水资源问题,为流域水资源管理和节水型社会建设耗水控制和节水方案提出建议. 相似文献
790.
David Evans 《Geoforum》2011,42(5):550-557
In the context of a string of economic crises that have affected major world economies between 2007 and 2009, there seems to be a certain amount of overlap between debates around these issues and debates around long term environmental problems such as climate change. One of the interesting points of overlap is a renewed interest in notions of austerity with optimistic commentators offering up hope that a (re)turn to frugality represents a unique opportunity for the pursuit of sustainable consumption. Against this backdrop the analysis sets out an approach to frugality as a social practice and drawing on a qualitative study of persons who identified themselves as attempting to reduce their environmental impacts, it considers the links between frugality and sustainable consumption. Crucially, a distinction is drawn between thrift and frugality in relation to: (1) the scale at which they exercise care and compassion; (2) their relationship to the normative expectations of consumer cultures, and; (3) their consequences in terms of environmental impacts. Taking these distinctions alongside historical analyses of changing consumption patterns, a note of caution is offered that the passage from the economic downturn to sustainable consumption may not be as clear as might be hoped. 相似文献