This week is the 10th International Symposium on Landslides and Engineered Slopes, which is a once every four years get together. This time round it is being held in Xi’an in China, which is particularly appropriate given the recent events a few hundred kilometres to the southwest. The organisers managed to timetable a session of two keynotes and six other presentations on landslides associated withe the earthquake. The session was …

Many thanks to reader Ripendra for alerting me to the following, and indeed for doing nearly all the work for this post. The 14th June 2008 earthquake in Japan is known to have triggered a number of landslides, as per earlier posts, but the most notable appears to have occurred at Aratozawa Dam in Miyagi prefecture. The Aratozawa Dam (Figure 1) is a rockfill dam used for flood control, irrigation …

At 08:43:46 local time on Saturday 14th June 2008 a magnitude Mw=6.8 (USGS initial estimate) struck eastern Honshu in Japan. Although this earthquake (now being called the Iwate-Miyagi Inland Earthquake) was not particularly large, it occurred at a shallow depth (10 km) below an area that is quite mountainous. This is an areas that is very landslide prone anyway, being subject to active tectonic processes and frequent typhoon rainfall events. …

At 08:43:46 local time on Saturday 14th June 2008 a magnitude Mw=6.8 (USGS initial estimate) struck eastern Honshu in Japan. Although this earthquake (now being called the Iwate-Miyagi Inland Earthquake) was not particularly large, it occurred at a shallow depth (10 km) below an area that is quite mountainous. This is an areas that is very landslide prone anyway, being subject to active tectonic processes and frequent typhoon rainfall events. …

Xinhua is today reporting the following:Nearly 9,000 people in a quake zone were evacuated on Tuesday for fear that huge cracks on a mountain could lead to further disasters. Many crevices, measuring up to 1,500 meters long, 250 m high and 50 centimeters wide, have been spotted on the Shiziliang Mountain in the Qingchuan County seat, Guangyuan City, since Sunday, threatening about 50,000 people and quake-relief soldiers. Part of the …

In previous posts I have warned that landslides will wreak a terrible toll in the aftermath of the earthquake. Sadly, this appears to be all too true. Xinhua is today carrying this report: More than 200 relief workers, engaged in repairing the broken roads in the quake-stricken Sichuan Province, had been buried in mud flows over the past three days, said Dai Dongchang, an official with the Ministry of Transport …

I thought it would be useful to summarise the key issues / threats associated with landslides in the aftermath of the Sichuan earthquake that I can see at the moment: Delayed landslides from the main earthquake: there is some evidence that there can be a substantial delay between the earthquake and occurrence of large-scale landslides. This is because: i) in some cases pore pressures in slopes take some days to …

Reports and images are now emerging of the complete burial of three villages, Donghekou, Ciban and Kangle, located on the Qingzhu river in Sichuan Provinc as a result of (separate) landslides in the Sichuan Earthquake. In particular, images are now available of Doghekou, which is one of the landslides that has blocked the river upstream of Beichuan. These three landslides have together entombed an estimated 300 families, which would indicate …

Now that there is a brief weather window, satellite imagery is starting to emerge of the Sichuan Earthquake zone. At present most of these images are too low resolution to allow detection of the real damage to the buildings (which is notoriously difficult to achieve), but they are excellent for looking at landslides. The best to date that I have seen has come from the Taiwanese Formosat-2 instrument, which is …

Some information is now becoming available about the impact of landslides in Beichuan. I have blogged before about this. However, a report in the Chinese Economic Observer online is now beginning to highlight just how bad the problem actually has been. This report states the following: In fact, landslides triggered by the May 12 earthquake had exacerbated the destruction in Beichuan. Take Maoba Middle School for instance, all traces of …