Yungay is a small village that lies about 60 km (37 miles) north of Huaraz. In 1962 an avalanche of rock, ice, and snow broke loose from the North face of Huascaran peak. It roared into the Santa Valley, wiped out several villages and killed more than 3,000 people. But this was only a warning from the mountain about what it would do next. On 31 May 1970, a severe earthquake (magnitude 8 on the Richter scale) rocked the valley.
The trembling earth broke loose a massive amount of rock and ices from the west side of the north half of the Huascaran massif. The size of the chunk of mountain that was broken loose is staggering. Estimates are that it was over 914 meters (3000 feet) wide and one mile long. The initial movement of what must have been more than 10 million cubic meters of ice and rock was almost purely vertical. It gathered so much energy so quickly that it steamrolled towards the hapless town of Yungay at an average speed of over 200 km/hr (124 mile/hr). Much of the descending piece of the mountain may have even been airborne for several seconds even after its initial plunge.
More Information:
