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The most "renowned or
infamous" volcano of Iceland, Hekla, is situated on a 25 miles
long volcanic fissure. The
volcano itself is about 3 miles long and about 5000 feet high.
It is estimated to be 6000-7000 years old and the life
expectancy of such central volcanoes is about 100.000 years according
to geologists. Presumably,
the number of Hekla's major eruptions is close to 20 during historic
times and minor eruptions in its vicinity about 25.
The first documented eruption in 1104, devastated the inhabited
valley Thjorsardalur and other areas further inland.
One of the vastest eruptions in the year
1300, split the mountain apart. The
booms were heard in the northern part of the country and the plume and
ashes created such darkness there, that no one dared to go fishing.
Farms collapsed during the earthquakes and the following famine
demanded many human lives.
This
eruption lasted a whole year.
In 1510, Hekla emitted its products over such great distances, that a
heavy stone
caused a fatal casualty 28 miles away.
During a major eruption in 1693, 14 craters were active
simultaneously. This
eruption devastated 50 farms for a while. Still another major eruption in 1766, which lasted two years
with intervals, showed 18 craters active at the same time. The eruption of 1845 lasted 7 months. In 1947, the eruption lasted 13 months uninterrupted.
At that time the plume reached the height of 20 miles.
About one km³ of tephra, which covered about 40 km² of land,
was produced. One fatal casualty among the scientists on the spot occurred.
In 1970, a minor eruption devastated large grazings in the
central highlands and fluoride poisoning was experienced.
Other
minor eruptions took place in 1980, 1981, 1991 and the most recent one
started at 18,15 on February 26th 2000.
The 7 km long volcanic fissure was active in the beginning and
the lava flows ran down the eastern slopes.
Within one hour of the eruption they had reached the
surrounding lowland areas and the lava production was considered
rather large in volume. This
eruption seemed to behave similarly to the 1991 eruption in the
beginning. The next day
the southeast part of the fissure remained active and the lava
continued flowing, a branch of it to the southwest.
Lava was flowing in a wide stream down the northwest shoulder
in the direction of the Skjolkviar (1970 eruption).
The plume was carried to the north the first day and the second
day to the south-southeast across the Myrdals Glacier to the sea and
the power of the eruption dropped to 90%.
It reached an altitude of about 13 km in the beginning.
On the third day, the eruption still diminished to 5% of its
initial power and the plume stretched towards southeast.
Fine ash powder was spotted on Svalbard.
Officially the eruption ended on March 8th.
Hekla is among the best known volcanoes of the world.
Many
Europeans believed that Hekla was one of two known entrances of Hell
(+Stromboli). Many extraordinary and dreadful legends about the volcano
existed and no one climbed it until 1750, when two naturalists
ventured to the top. Up
there, they could not find anything to substantiate the legend and
since then, the mountain is frequented by all kinds of people.
The easiest way up is from the north.
On a fine day, the view from up there is simply unbelievable. |