Mount St Helens, a remarkable volcano that erupted causing the largest avalanche ever recorded
Mount
St Helens, once known as 'the Fuji of America' for its symmetrical beauty
similar to that of the famous Japanese volcano, with its graceful cone
top capped by snow is now largely gone.
Today, visitors come to Mt St Helens to marvel at the destruction and
devastation caused by this natural disaster as well as to gaze in awe at
nature's remarkable ability to recover.
On 18 May, 1980 at 8:32 am, the north face of Mount St Helens collapsed
in the largest debris avalanche ever recorded, caused by an underlying
earthquake that measured 5.1 on the Richter scale. The volcano's height
was reduced from 2,950 meters (9,677 feet) to 2,550 meters (8,364 feet).
Within seconds of the earthquake, the volcano's bulging northern side
slid away, triggering a destructive, lethal lateral blast of hot gas,
steam and rock debris that swept across the landscape. Blasted with
temperatures as high as 300°C (572°F), snow and ice on the volcano
rapidly melted, forming violent torrents of water and rock that rushed
from the volcano. Within moments, a massive cloud of ash thrust 19 km
(11.8 miles) into the sky, and the strong winds carried more than 540
million tons of ash across 57,000 sq km (35,418 sq miles) of the western
United States.
Shortly afterward, a cloud of ash rose skyward, while a pyroclastic flow
sent even more ash down the Toutle and Cowlitz rivers, dragging anything
and everything in its path downstream, destroying roads, bridges, homes
and businesses and blanketing much of the Pacific north-west with a grey,
dusty powder.
Even before its eruption, Mount St Helens was not one of the highest
peaks in the Cascade Range, it was only the fifth highest peak in
Washington. What was impressive was its handsome outline against the
neighboring craggy peaks.
Today, over a quarter of a century later, the signs of healing are
evident. The pre-eruption landscape, once dominated by dense coniferous
forests and clear streams and lakes has begun to re-establish itself. The
lower forests once dominated by Douglas fir and western hemlock have
started to re-grow and tourism has returned to this area of scenic
beauty. The volcano is still active, some areas nearby are not open and
roads may be closed at short notice.
