Hverfjall Crater
Husavik, Iceland
Earth's Natural Wonders in Europe & Middle East
Age of Hverfjall Crater: 2,800 years
Height of cinder cone: 656 feet (200 meters)
	Hverfjall Crater[1]

 

The Hverfjall eruption occurred ~2500 BP in the southern part of the Krafla fissure swarm in
northern Iceland. Detailed fieldwork and stratigraphic mapping conducted during the summer
of 2005 show that the eruption occurred along a NNE-SSW trending fissure and that activity
at least two vents were overlapping.
The initial activity was concentrated at Hverfjall in the southern part of the fissure, which was
at that time covered by a shallow lake and deposits generated during that phase are mainly of
phreatomagmatic fallout origin. As the eruption progressed a new vent opened up at
Jarðbaðshólar (located approximately 3.5 km NNE of Hverfjall). The Jarðbaðshólar vent was
situated on land and formed a scoria cone with associated lava flows. Activity was presumably
ongoing at the Hverfjall vent during this time. After the cessation of activity at Jarðbaðshólar
the focus shifted once again back to Hverfjall. However, the Hverfjall deposits formed after
the Jarðbaðshólar scoria cone are almost exclusively base-surges (with minor fallout). The
change from fallout to base-surges is probably the result of lowering of the eruption rate at
Hverfjall (as two active vents were drawing from the same magma reservoir simultaneously).
The base surge deposits are found both north and south of the Hverfjall crater and can be
traced as far as 5 km from the vent (and up to ~100 m uphill on Námafjall). The base-surge
deposits display a “drying-up” with distance from the vent. The surges display wet features
within a radius of approximately 2 km from the vent (plastering, accretionary lapilli, and soft
sediment deformation). Surges found at distances exceeding 2 km from the vent all display
dry features such as strongly grain-segregated layers.[2]

	The second volcanic cycle, the Hverfjall cycle, began 2500 years ago with a gigantic but brief eruption, which formed the explosion crater (tephra ring ) Hverfjall (also named Hverfell). An eruption in Jardbadshólar followed, producing the lavafield between Reykjahlíð and Vogar. Approximately 200 years later a vast lava flow, the Younger Laxá-lava, was erupted (see above). The lava dammed up the present Lake Mývatn and also the lakes Sandvatn, Grænavatn and Arnarvatn.[4]
The Hverfjall crater[3]

The primeval, rugged splendor that makes Iceland so dramatic has been created by one of the most powerful forces on Earth. It was formed less than 20 million years ago from volcanic activity on the floor of the Atlantic Ocean, and shaped by large ice-age glaciers.
Hverfjall Crater was created during a short but powerful eruption some 2,800 years ago. The area formed the southernmost part of an eruptive fissure, as molten magma rose through this fissure it met the waters of a lake, causing a phreatomagnetic explosion. The ensuing blast prouced a wide crater of ash and pumice. Measuring nearly 1 mile (1.6 km) wide. Hverfjall's cinder cone rises 656 feet (200 m). All around lies evidence of the turmoil steaming beneath the surface: the eruptions of the 1720's and the Krafla volcanic fires of the 1970's left the adjacent landscape littered with fumaroles and bubbling mudpools.
Hverfjall is situated to the north of the country's fourth largest lake, Myvatn, a true oasis in a lava desert. Amid volcanic flows and craters, ash cones and geysers, thousands of wildlife flock to the region annually[5]

Finally made it to the top and was rewarded with amazing view of Lake Mývatn area.

You tube video of Hverfjall Crater