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121.
根据四川省气象灾害多发、频发的特点,提出四川省气象灾害防御的主要措施和对策,探讨了有关气象灾害防御的保障措施. 相似文献
122.
利用FLAC3D软件对四川省雅安市汉源县二蛮山滑坡坡体进行建模,模拟降雨滑坡过程,并进行应力应变特征及稳定性计算分析,从而为深入研究地震及降雨诱发再次滑坡及防灾减灾提供可靠依据。研究中假设地震工况,对边坡进行详细的动力分析,得到了各监测点动力特征曲线;通过降雨工况下坡体稳定性系数分析得到了不同强度折减安全系数。研究结果表明,滑源区相对特殊的地形条件和地质构造以及不利的结构面组合是滑坡的基础;前期强降雨期间饱水加载以及大量雨水沿斜沟张裂结构面的下渗软化作用,是诱发滑坡发生的关键因素。 相似文献
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Jian Cao Zhijun Jin Wenxuan Hu Yijie Zhang Suping Yao Xulong Wang Yueqian Zhang Yong Tang 《Marine and Petroleum Geology》2010
Calcite veins and cements occur widely in Carboniferous and Permian reservoirs of the Hongche fault zone, northwestern Junggar Basin in northwest China. The calcites were investigated by fluid inclusion and trace-element analyses, providing an improved understanding of the petroleum migration history. It is indicated that the Hongche fault behaved as a migration pathway before the Early Cretaceous, allowing two oil charges to migrate into the hanging-wall, fault-core and footwall reservoirs across the fault. Since the Late Cretaceous, the Hongche fault has been sealed. As a consequence, meteoric water flowed down only into the hanging-wall and fault-core reservoirs. The meteoric-water incursion is likely an important cause for degradation of reservoir oils. In contrast, the footwall reservoirs received gas charge (the third hydrocarbon event) following the Late Cretaceous. This helps explain the distribution of petroleum across the fault. This study provides an example of how a fault may evolve as pathway and seal over time, and how reservoir diagenetic minerals can provide clues to complex petroleum migration histories. 相似文献
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Four results of the rupture process of 14 April 2010 Yushu, Qinghai, earthquake, obtained by inverting the broadband seismic data of Global Seismographic Network (GSN) based on the inversion method of earthquake rupture process, were compared and discussed. It is found that the Yushu earthquake has several basic characteristics as follows: ① There exist two principal sub-events which correspond to two slip-concentrated patches being located near the hypocenter and to the southeast of the epicenter. The rupture of the slip-concentrated patch to the southeast of the epicenter broke though the ground surface; ② The peak slip and peak slip-rate are about 2.1 m and 1.1 m/s, respectively, indicating that the Yushu earthquake is an event with large slip-rate on the fault plane; ③ Overall the Yushu earthquake is a unilateral rupture event with the rupture mainly propagating southeastward. The strong focusing of the seismic energy in the southeast of the epicenter due to the "seismic Doppler effect" reasonably accounts for the tremendous damage in the Yushu city. 相似文献
128.
Hyo Jin Lee Sang Hee Hong Moonkoo Kim Sung Yong Ha Soon Mo An Won Joon Shim 《Ocean Science Journal》2011,46(2):95-103
Masan and Haengam Bays in Korea are highly polluted and semi-enclosed. Domestic and industrial effluents are directly or indirectly
discharged into the bays through sewage treatment plants (STP) and creeks. In this study, 15 dissolved sterol compounds were
determined in order to understand their sources and relative contribution. Freshwater samples were taken from 13 creeks and
at two STP sites on a monthly basis. Total dissolved sterol concentrations ranged from 993 to 4158 ng/L. The concentrations
of sterols in winter were higher than in summer. Among the sterols analyzed, cholesterol, β-sitosterol, coprostanol and cholestanone
were major compounds in creek water. Seawater samples were concurrently collected at 21 stations in Masan Bay. Total sterol
concentrations ranged 118–6,956 ng/L. Inner bay showed high concentrations of sterols in summer, while outer bay showed high
sterol concentrations in winter. Among the sterols, cholesterol, β-sitosterol and brassicasterol were major compounds in seawater.
In order to examine the contribution of urban sewage, the concentration of coprostanol and fecal sterol ratios were calculated.
Most of the creek water, inner bay and near STP outlet samples were affected by sewage. Terrestrial organic matters accounted
for a high proportion of dissolved organic matter origin. Fecal origins were relatively high in the inner bay areas and in
the STP outlet, while sterols of marine origin were high in the outer bay areas. 相似文献
129.
为探索采动影响下的断层活化突水机理,开展断层破碎岩体剪切变形与渗透性演化试验研究。基于流固耦合原理设计一套破碎岩体压剪渗流试验系统,实现破碎岩体剪切变形与渗流的耦合过程,开展多因素影响下的破碎岩体剪切−渗流耦合试验,获得连续剪切过程中颗粒级配和初始孔隙率对孔隙率和渗透性参量的影响规律。结果表明,连续剪切条件下,破碎岩体的渗透率和孔隙率变化过程大致相同,可分为3个阶段:缓慢增长阶段,破碎岩石颗粒由散乱状态向有序的组织结构调整;加速增长阶段,破碎岩石颗粒剪切膨胀;增速放缓阶段,破碎岩体颗粒的剪切变形在围压的约束下达到动态平衡。试样Talbot指数越小或初始孔隙率越大,渗透率和孔隙率敏感性越强,渗透率和孔隙率越大;非Darcy流
130.
土地是实现可持续发展的基础性资源和重要资产保障。扎实推进经营性土地使用权招标拍卖挂牌出让制度,通过市场机制形成土地价格,可以提高土地资源利用率,有效遏制土地资产的流失,最大限度地获取经济效益、社会效益和环境效益,促进可持续发展,并可以抑制权力进入市场,从源头上预防和治理腐败。近两年来,莱芜市土地市场与土地资源管理工作虽然取得了一定成绩,但仍存在土地市场不够规范的问题,全市土地资产经营的机制有待进一步健全完善。同时,个别单位、部门和同志对经营性土地使用权以招标拍卖挂牌出让的方式取得的严肃性还认识不足,以言代法… 相似文献