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排序方式: 共有22条查询结果,搜索用时 62 毫秒
1.
陈国顺 《华南地震》1991,11(2):40-46
本文以滑波理论为依据,总结了山西地震带的两种不同特点的滑坡。即:振荡式滑坡及触发式滑坡。虽然两种滑坡都可分为变形、解体、滑动、毁灭等四个阶段,但其动力不同。振荡式滑波的滑动面倾角小,因而滑力来源于强震振动,而触发式滑坡的滑动面倾角大,因而滑力来自滑体本身静荷载。对两种滑坡的研究对预防及减轻强震带来的次生灾害有重要的意义。  相似文献   
2.
山西侯马—河津一带西汉初期的强烈地震   总被引:1,自引:0,他引:1  
陈国顺  黄振昌 《中国地震》1993,9(3):276-285
1989年至1987年间,在国家地震局招标合同项目《全新世古地震的研究方法和确定标志》工作中,笔者在山西省侯马至河津一带,发现了大规模地震断层和许多古地震遗迹。本文就是在此基础上,对黄土中的古地震遗迹进行了总结,分析研究了古地震的分布和特征,讨论了侯马至河津一带西汉初期强震的规模和震中。  相似文献   
3.
介绍了FortranM的基本概念和特点。FortranM是一个支持分布式环境中并行计算的Fortran语言新成员,它在Fortran77上扩充而成,不仅能支持数据并行程序设计,而且能支持任务并行程序设计。在重磁数据处理中,常常要进行大计算量的运算,如果采用并行计算方法,可以大大提高低档机器的运算能力,降低运算费用,缩短处理周期。本文用FortranM把GMPS改造成并行计算系统GMPS-FM,经实际运行,效果良好,最后对测试结果作了分析。  相似文献   
4.
到目前为止本省内早寒武世尚未发现有梅树村期和筇竹寺期沉积,仅有沧浪铺期和龙王庙期沉积存在。在济源—博爱—武陟一线以南地区有沧浪铺阶辛集组、朱砂洞组和龙王庙阶馒头组。该线以北只有龙王庙阶辛集组和馒头组。辛集组是个受特定环境控制的穿时地层单元。早寒武世沧浪铺早—中期(辛集组)沉积环境是潮下浅水陆棚和滨岸潮下带、滨岸潮坪潮间带。沧浪铺中—晚期(朱砂洞组)沉积环境是滨岸碳酸盐潮坪缓坡—潮间—潮上蒸发坪和潮间蒸发岩洼地以及潮下碳酸盐浅水缓坡。龙王庙期(馒头组)沉积环境是滨岸碳酸盐岩潮坪缓坡和潮下碳酸盐岩浅水缓坡。早寒武世痕迹化石主要产于三个层位,可分为H-T组合和L-B组合。前者为潮下浅水陆棚风暴环境痕迹组合,后者为潮间—潮上低能泥坪环境痕迹组合。早寒武世痕迹化石共11属(1新属)、16种(1新种、1相似种、10未定种)。  相似文献   
5.
公元512年山西省北部7.5级地震发震断层初探   总被引:2,自引:0,他引:2  
丁学文  程新源 《地震研究》1999,22(4):390-396
根据野外断层露头,探槽及热释光年龄样数据,揭示了大同盆地内黄花梁-山自皂断层为公元512年强震的发震断层,这对确定该次地震宏观震中及研究大同盆地地震活动性具有重要意义。  相似文献   
6.
2005年12月在蒙特利尔举行的《京都议定书》第一次缔约方会议决定按议定书第三条第九款的规定启动附件一缔约方(发达国家和经济转轨国家)2012年后温室气体减排指标的谈判,即第二承诺期谈判,并成立了“不限名额特设工作组”(以下简称工作组)。第二承诺期谈  相似文献   
7.
河南盐业开发起步较晚,盐资源利用不尽合理,产品开发单一,盐厂限产压库,化工厂大量的生产用盐却从外省调入。作者为河南省盐业的发展提出了一些切实可行的办法和思路,供决策者参考。  相似文献   
8.
The indoor PM2.5 aerosol samples for charcoal broiling source under Chinese traditional charbroiling and the ambient fine aerosols samples (PM2.5) were collected in Beijing to investigate the characteristics of the charcoal broiling source and its impact on the fine organic aerosols in the atmosphere. The concentrations of 20 species of the trace organic compounds, including polycyclic aromatic hydrocarbons (PAHs), fatty acids, levoglucosan, and cholesterol in PM2.5 were identified and quantified by GC/MS. The total PAHs and fatty acids emitted from charcoal broiling to PM2.5 were 8.97 and 87,000 ng mg−1 respectively. The concentrations of the light molecular weight (LMW) 3- and 4-ring PAHs were much higher than those of the high molecular weight (HMW) 5- and 6-ring PAHs. Fatty acids were the most abundant species in source profile, accounting for over 90% of all identified organic compounds. More polyunsaturated fatty acid (linoleic acids) than the saturated fatty acid (stearic acids) emitted in the cooking. Charcoal broiling is a minor source of PAHs compared to the source of biomass burning. Comparing the ratios of levoglucosan/fatty acid and levoglucosan/cholesterol in the charcoal broiling samples to the ambient samples, it is evident that meat cooking is an important source of fatty acids, but a less important source of cholesterol. Cooking, as one of the source of fine organic particles, plus other anthropogenic sources would be related to the formation of the severe haze occurred and spread over the urban atmosphere in most of the cities of China in the past several years.  相似文献   
9.
The chemistry of heavy haze over Urumqi,Central Asia   总被引:1,自引:0,他引:1  
A sampling campaign of aerosols over Urumqi from 2001–2007 and soil samples in the surrounding areas were carried out to investigate the severe air pollution in Urumqi, a typical inland city, located in the center of Asia. Urumqi is one of the heavy polluted cities in the world, as the days of haze spanned over one third of the year and accounted for 60–80% of the heating period for the past 6 years. High concentration of fine aerosols, frequent occurrence, and rapid formation of heavy haze were the three main characteristics. With comparison of the pollution elements, As, Cd, and S, and the ratio of Ca/Al in aerosols and soils in those sites located on the south of Jungger Basin as tracers, it was found that As, Cd, and S highly enriched in the aerosols over urban Urumqi were not only from the re-suspended road dust but also from the soil transported from south of the Jungger Basin. Different from the most cities in China, the high concentration of sulfate in Urumqi was partially from the primary soil dust transported from the surrounding areas. The mixing of the local anthropogenic aerosols with the soil transported from outside the city was the main source of the high sulfate concentration. Ammonium salts were higher than the summed equivalents of SO42−, NO3, and Cl in Urumqi and much higher than that in other Chinese cities. The total water soluble ions and the total ammonium salts were as high as 57.8% and 51.0% in PM2.5. The high concentration of soluble salts with high hygroscopicity, especially ammonium and sulfate salts, were the main factors contributing to the heavy haze over Urumqi.  相似文献   
10.
本文介绍了1989年12月25 日侯马4.9Ms地震后对地震区地震烈度、震害、宏观异常现象和社会经济影响的调查结果以及地震现场的一点体会。  相似文献   
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