The Grímsvötn is a volcano located in the highlands on the northwestern side of the Vatnajökull ice-cap (Iceland). The caldera is at 64°25′N 17°20′W, at an elevation of 1,725 m. The Grímsvötn is one of Iceland's most active volcanoes. It has a complex of calderas, and a subglacial caldera lake sustained by geothermal heat.
The subglacial Grímsvötn central volcano, lying within a volcanic zone directly above the core of the Iceland mantle plume, is one of the most active on Earth (comparable to Hawaii).
On our way, on the Ice cap.
Visiting some solfataras zone on the ice cap.
Going down the caldeira.
The edge of the caldera (south).
Chronostratygraphy of the past eruptions (black hash into the ice).
Huge cracks on the lake side.
Open cracks (crevasse) on the lake ice.
Open cracks on the lake ice, close to the high thermal activity zone.
Global view of the caldera.
An avalanche occured (south side).
The caldera and the lake seen from the west part.
We published a book on Iceland and a book on volcanoes: A) Detay M., Detay A.-M. — Islande - splendeurs et colères d’une île. Belin Ed. 208 p. (2010). ISBN 978-2-7011-5762-7here B) Detay M., Detay A.-M. — Volcans - de feu et d'eau. Belin Ed. (2013). ISBN 978-2-7011-7561-4here
We wrote a paper about Iceland and the Grímsvötn:
1) Detay M., Hróarson B. — L’Islande une île extraterrestre, in LAVE, revue de l’association de volcanologie européenne, 195, September 2019, 9-18 (2019). You can download the paper here