Brief report on a coastal landslide affecting a road in San Pedro, California

A review of a new paper that has identified a new, large, ancient landslide in northern California. The landslide dam had a surprising impact on the local fish population

The remarkable slope failures in the sediments at Lake Condit in Washington State USA, which were caught on video, illustrate the processes associated with slope failure during rapid draw-down.

Filling of the lake behind the slide at Attabad continues, with the reported freeboard being 1.98 metres as of yesterday afternoon.  I have not yet received a value for today – I will update the figures when this comes through.  For now the freeboard time graph looks like this: This would suggest a likely date of overtopping of 28th to 29th May, but once again caveats apply.  It is now …

Although all eyes, and increasingly those of the media (which is showing considerable interest in this blog), are on Attabad, other landslides are happening around the world as we enter the rainy season in many landslide prone areas of the Northern Hemisphere.  In the last few days a number of significant landslide events have occurred: 1. A landslide-induced rail crash in China this morning.Xinhua reports that an 8000 cubic metre, …

NASA have released a new ASTER image of the lake that continues to build behind the landslide at Attabad in Hunza, N. Pakistan.  Included in this image is the outline of the lake as it was in their image in March, showing the increase in surface area: A couple of things to note on this image:1. The red areas indicate vegetation.  Given that this area is very close to being …

Reports suggest that ground movement has ceased in the Rivermist subdivision, which suffered a fairly spectacular retaining wall failure over the last few days. Attention is now focussing upon that retaining wall – and in particular on why it failed. This is a pretty key issue given the potential liabilities and its magnitude – the wall is 1000 feet (>300 m long). Press reports note two interesting aspects of this …

Amongst the (appropriate) focus upon Haiti at the moment, we must of course remember that landslides do not stop elsewhere. So, here are two important ongoing stories: 1. Potential landslides in California this week:The US National Weather Service has issued a series of warnings for very heavy rainfall in California this week, with the pontential for landslides, flash flood and debris flows. For example: …Flash flooding and debris flows possible …

Regular readers will know that one of my interests lies in trying to get a better understanding of the loss of life associated with landslides. A key realisation of this work for me has been that earthquake-triggered slides cause a very substantial proportional (probably in fact the majority) of fatalities is mass movement events. Unfortunately our understanding of seismically-driven landslides, and their impacts, remains poor, certainly in comparison with rainfall …

Thanks to reader Chingying Tsou, who has answered my request for information about the geological structure of the Hsiaolin landslide. He has provided a link to the website of the Sino-Geotechnics Research and Development Foundation, which provides the key information. The page is in Chinese, but the diagrams are really helpful, as is the Google translation. So here is a topographic map of the landslide site, with the major faults …