Satellite images, taken before and after the avalanche, shows the vast extent of the disaster. Debris and ice filled the Genaldon Valley from the Kolka Glacier Cirque to the Gates of Karmadon distance of about 18 km (11 mi).
The Kolka-Karmadon rock-ice slide occurred on the northern slope of the Kazbek massif in North Ossetia, Russia on the 20th of September 2002 following a partial collapse of the Kolka Glacier. It started on the north-northeast wall of Dzhimarai-Khokh, 4,780 m (15,680 ft) above sea level, and seriously affected the valley of Genaldon and Karmadon. The resulting avalanche and mudflow killed 125 people (including a film crew of 27 people and Russian actor Sergei Bodrov Jr.).
A 150 m (490 ft) thick chunk of the Kolka Glacier travelled 32 km (20 mi) down the Karmadon Gorge and Koban Valley at over 100 km/h (62 mph). The outflow of mud and debris measured 200 m (660 ft) wide and 10 to 100 m (33 to 328 ft) thick. Two villages along the gorge were under surveillance as flood waters backed up along the choked rivers. It finally came to rest in the village of Nijni Karmadon, burying most of the village in ice, snow, and debris. On September 25, a first round of explosives intended to break up the avalanche flow was unsuccessful in reducing flood waters lapping through the village of Gornaya Saniba.
Haeberli, W.; Huggel, C.; Kaeaeb, A.; Polkvoj, A.; Zotikov, I.; Osokin, N. (6–11 April 2003). "The Kolka-Karmadon rock/ice slide of 20 September 2002 an extraordinary event of historical dimensions in North Osetia (Russian Caucasus)". EGS - AGU - EUG Joint Assembly, Abstracts from the meeting held in Nice, France. Bibcode:2003EAEJA.....1978H.