Shield volcanoes of Iceland
There is a high number of shield volcanoes in Iceland, island volcanoes (Surtsey), volcanoes which have their origin in the warm phases of the Ice Age, part of them heavily eroded and finally some big shield volcanoes from the end of the last cold phase which are about 9.000 years old.
The island of Surtsey
[edit]Surtsey is the youngest shield volcano of Iceland and originated in a series of eruptions which started with a submarine phase in 1963 and ended by subaerial production of lava and ash in hawaiian style in 1967. Since then, heat within has changed the volcanic ash into erosionresistant tuffstone and the sea has eroded away other parts of the island. It may only be visited by scientists with special permission.
Surtsey: The making of a shield volcano
[edit]-
Phreatomagmatic eruption at Surtsey, 1963: The eruption breaks through the water surface
-
First phase - Surtseyan eruption
-
Second phase - Hawaiian (shield volcano) eruption
Shield volcano Surtsey
[edit]-
Surtsey in 1999
-
Surtsey in 2007
-
Surtsey in 2008
-
Craters
Pre-Holocene shield volcanoes of Iceland
[edit]There are many more or less eroded shield volcanoes from the warm interims of Ice Age. Only the most erosion resistant remnants of some of them can still be seen, like Þyrill in the Hvalfjörður area. Others are often spiked with younger volcanic landforms like the ones on the peninsula of Reykjanes near Reykjavík.
-
Þyrill
-
Another remnant of the same shield volcano
-
A shield volcano and its parasitic cones and ridges behind Kópavogur
-
A shield volcano with parasitic cones
Shield volcanoes from the Holocene
[edit]Holocene started in Iceland around 11.000 years ago when the Ice Age glaciers began to melt. At the same time, the land began to rise and melt production in the mantle intensified. This lead to heightened eruptive activity and not least to the formation of shield volcanoes. Some well known big shield volcanoes date from about 9.000 years ago.
-
Hrafnabjörg and other subglacial landforms
-
are placed within the surface of an shield volcano (Þingvellir National Park) from the end of Ice Age
-
Skjaldbreiður in the upper middle
-
Þingvellir, with Skjaldbreiður in the background
-
Trölladyngja in the Askja region
-
Trölladyngja