A large shield volcano in the Danakil desert (Ethiopia)
Shield volcanoes are volcanoes that mainly erupt fluid (usually basaltic) lava flows that are able to travel over long distances and thus construct over time broad, gentle slopes. They are called shield volcanoes, because they resemble the shape of a warriors' shield.
Shield volcanoes are volcanoes that mainly erupt fluid (usually basaltic) lava flows that are able to travel over long distances and thus construct over time broad, gentle slopes. They are called shield volcanoes, because they resemble the shape of a warriors' shield.
While stratovolcanoes, the other major morphological type of volcanoes, are representative for most subduction-type volcanoes, sh... -> See whole entry
Skylights are openings in the roof above a lava tube, from where the flowing lava flow can be seen. Usually, these holes are caused by the simple collapse of the roof of the tube.
Volcanology: volcanic smoke ring, gas ring, steam ring
Etna's Bocca Nuova crater in 2000, emitting smoke rings
Smoke ring detail (Etna)
A rare phenomenon, where a visible vortex ring of steam and gas is expelled from a volcanic vent.
Under special conditions, gas and steam expelled from a vent can form gas rings. It probably requires a particular geolometric configuration of a circular vent exit, as well as expulsion of gas in individual puffs with just the right velocity.
This phenomenon is quite rare, but has been witnessed at several volcanoes, including Stromboli and Etna. At Etna, a spectacular period lasting several mo... -> See whole entry
