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451.
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Hao Xiong 《地震学报(英文版)》1992,5(2):407-412
The paper briefly reviews the recent advances and the main trend, as well as the major subjects for future study in the research
on seismo-electromagnetic emissions. The preliminary results obtained show that the recently discovered electromagnetic emission
phenomena prior to earthquake events are objective facts and may be prospective precursor applicable for short term earthquake
prediction. Considering the complexity of the generation mechanisms, as well as the space coupling and the time variation
processes of the seismo-electromagnetic emissions, we must deeply study the essential connection between the precursory emission
phenomena and the seismogenic processes. Closely connect the field observations and theoretical research and try to comprehensively
diagnose by correlating with other precursors.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 254–258, 1991. 相似文献
454.
论湖南石门雄黄矿区矿化角砾岩成因类型 总被引:4,自引:0,他引:4
湖南石门界牌峪地区雄黄矿床中伴有各类化角砾岩。它们互不相连,外观圆形,有的聚集成群或呈完全弧立的山包,与围岩多呈刺穿状接触,角砾岩胶结物中微量元素同该区现代热泉体系沉积物类似,成矿溶液和角砾岩胶结物包裹体成分富Na^+,Ca^2+,Cl^-,HCO^-3和SO62-4,也与该区现代热泉水成分相似。 相似文献
455.
第四纪气候变化机制研究的进展与问题 总被引:3,自引:1,他引:3
自从20世纪50年代海洋沉积氧同位素记录被揭示以来,经典的陆地4次冰期理论被新的认识所取代,人们发现第四纪以来冰期—间冰期旋回远远不止4次,并且从深海沉积和陆地黄土获取的古气候变化记录与地球轨道参数变化可以对比,为揭示第四纪古气候变化机制构建了明确的框架。近年来有关末次冰期不稳定气候事件的揭示也为深入认识古气候变化特征提供了新的证据。然而冰期—间冰期旋回机制、南北半球在冰期—间冰期循环过程中的耦合机制以及气候不稳定事件发生机制仍然是困扰古气候研究者的重大问题。 相似文献
456.
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Jinge Wang Aijun Su Wei Xiang Hsin-Fu Yeh Chengren Xiong Zongxing Zou Cheng Zhong Qingbing Liu 《Landslides》2016,13(4):795-804
The original Badong County, Hubei, China, was mainly below the highest water level of the Three Gorges Reservoir, which is 175 m above sea level. The new downtown of Badong was rebuilt in the Huangtupo area between 1982 and 1991. After detailed geological investigation in the Huangtupo area, four independent landslides were identified, making it one of the largest and most harmful landslide group in the Three Gorges Reservoir area. Since 2003, abundant data have been obtained from the Huangtupo No. 1 sliding mass about rainfall, water level, earth surface deformation and deep deformation. The monitoring data indicate that the earth surface and deep deformation of this landslide is closely related to the seasonal rainfall and water level fluctuation of the reservoir. During increases in the water level, the earth surface deformation velocity decreases, and then increases obviously in the subsequent water level decreasing stage. Because the water level drawdown period overlaps with the rainy season in this area, the earth surface deformation is affected by both rainfall and water level. The deformation velocity of the earth surface caused by rainfall is about 5 mm/month, while that caused by water level decrease is 5–7 mm/month. On the contrary, the deformation velocity of the deep sliding mass accelerates 2 to 3 times faster than average during water level increase. The distinction of surface and deep deformation regulations indicates that the effects of seasonal rainfall and water level fluctuation on the stability of reservoir wading landslides are different. Based on all monitoring data, we also found that the Huangtupo No. 1 riverside sliding mass is creeping seasonally during the seasonal rainfall and periodic reservoir water level fluctuation. The deformation velocities of the east regions of the sliding body indicate acceleration, making these regions even more dangerous. 相似文献
459.
460.
Jianguo Xiong Youli Li Supei Si Shenghua Lv Yiran Wang Yuezhi Zhong Weilin Xin Hongjuan Ci 《Arabian Journal of Geosciences》2016,9(18):704
Earthquake is the main driving factor of landslides, and a large number of empirical formulas for seismic parameters have been proposed. This article studies a rock avalanche triggered by a paleoearthquake and two trial trenches in Yongji, Shanxi Province. Six quartz samples were collected from different parts on the top of the boulder, and the youngest 10Be exposure age is 1173 ± 123 years, which is considered as the occurrence time of the rock fall. The trenches excavated near the boulder infer that there was an earthquake between 2000 ± 110 and 465 ± 45 cal a bp in the north Zhongtiao Shan (NZS) fault with a maximum vertical displacement of 1.5 m and the surface rupture length (SRL) of ~35 km corresponding to a magnitude (M S) of 6.70 ± 0.12 based on the displacement. Taking into account the occurrence time and minimum magnitude triggering the rock fall, the latest paleoearthquake revealed by trenches may be the forcing factor. Furthermore, according to historical records of Yongji, the earthquake of magnitude 6 in ad 793 is in consistency with the occurrence time and magnitude of the earthquake triggering the landslide. Therefore, the rock fall is related to the paleoearthquake revealed by the trenches, which may be the 793 Yongji earthquake. 相似文献