1 February 2023
The 15 September 2022 Jiujiawan landslide in Qinghai province, China
A new paper in the journal Landslides (Wang et al. 2023) describes the 15 September 2022 Jiujiawan landslide in Qinghai province in China. This was a large rainfall triggered failure that blocked the high speed Lanzhou-Xinjiang Railway, as well as destroying a number of roads.
The location of the landslide is 36.680, 101.772 (once again the coordinates given in the paper are slightly incorrect). This is the site of the landslide in a Google Earth image collected in July 2022:-
Wang et al. (2023) includes an image of the aftermath of the landslide:-
According to the authors, the landslide occurred in sandy mudstone interbedded with gypsum at the end of an abnormal period of rainfall, although the level of precipitation on the day of the failure was low. The failure is rotational – to me it appears that there were two blocks. The first, smaller, block has disintegrated to form the debris pile at the toe of the slope. The second remains intact, with several metres of displacement, forming the large scarp at the crown of the landslide. This displaced block will require careful management.
The major economic impact of the landslide was damage to the high speed railway. As the image above shows, the track was on an elevated section at the toe of the slope. The landslide hit five of the piers, one of which was displaced 7 metres, breaking away from its foundation. The line was closed in the vicinity of the landslide; satellite images suggest that this might still be the case today.
Fortunately there were no fatalities associated with the Jiujiawan landslide.
Wang, F., Chen, Y. & Yan, K. 2023. A destructive mudstone landslide hit a high-speed railway on 15 September 2022 in Xining city, Qinghai province, China. Landslides. https://doi.org/10.1007/s10346-022-02016-0