Volume 27 Issue 1
Feb.  2021
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ZHAO Dongliang, LANCUO Zhuoma, HOU Guangliang, et al., 2021. Assessment of geological disaster susceptibility in the Hehuang Valley of Qinghai Province. Journal of Geomechanics, 27 (1): 83-95. DOI: 10.12090/j.issn.1006-6616.2021.27.01.009
Citation: ZHAO Dongliang, LANCUO Zhuoma, HOU Guangliang, et al., 2021. Assessment of geological disaster susceptibility in the Hehuang Valley of Qinghai Province. Journal of Geomechanics, 27 (1): 83-95. DOI: 10.12090/j.issn.1006-6616.2021.27.01.009

Assessment of geological disaster susceptibility in the Hehuang Valley of Qinghai Province

doi: 10.12090/j.issn.1006-6616.2021.27.01.009
More Information
  • Received: 2020-02-22
  • Revised: 2020-04-03
  • Published: 2021-02-28
  • The Yellow River and Huangshui Valley, located at the northeast margin of the Qinghai-Tibet Plateau, are prone to geological disasters due to violent geological activities, large elevation difference and strong hydraulic power. In order to clarify the zoning of susceptibility of geological disasters in this area, an assessment index system is built by selecting factors such as geomorphology, slope, slope height, vegetation, lithology, rainfall, distance from faults, rivers and roads, using the information model to calculate the susceptibility index of collapse, landslide, debris flow and comprehensive geological disasters. The susceptibility of geological disasters in the study area can be divided into five grades: extremely high, high, medium, low and extremely low. The result shows that the extremely high susceptible areas are mainly in the valley areas, accounting for 2.03%, including the middle and lower reaches of the Yellow River and the Huangshui River in Guide county, Huangzhong county and Ledu county. The high susceptible areas are mainly in the areas on small and moderately undulating mountain basins, accounting for 21.2%. The medium susceptible area are mainly in the moderately undulating mountain areas, accounting for 23.45%, which belong to the transition areas of high and low susceptible areas. The low susceptible areas are mainly in moderately and sharply undulating mountain areas, accounting for 42.1%. The extremely low susceptible areas are mainly on the mountains such as the Lenglong mountain, Laji mountain and Xiqing mountain, accounting for 11.23%. The research result is of great significance to the disaster prevention and reduction in the Hehuang Valley and to the sustainable development of society.


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