Ljósufjöll

The Ljósufjöll volcanic system at the eastern end of the Snaefellsnes Peninsula is composed of a group of alkali olivine basaltic cinder cones and lava flows along short fissures on a roughly 90-km-long WNW-ESE line. The volcanic field is about 20 km wide at the eastern end and narrows to about 10 km on the west. It contains the largest outcrops of silicic rhyolitic and trachytic rocks in the Snaefellsnes volcanic zone, erupted during the mid- to late Pleistocene. Youthful-looking cinder cones and lava flows with morphologically pristine surfaces suggest numerous Holocene eruptions. The latest eruption post-dated the settlement of Iceland, and took place about 1,000 years ago.