Historical accounts of earthquakes associated with eruptive activity in the Askja volcanic system

Abstract

Scientific knowledge gained during the Krafla intrusive and eruptive activity in recent years facilitates reinterpretation of earlier rifting events, such as the Askja rifting episode of 1874-1876. Most of the intrusive activity during the Askja rifting episode took place during the first few months. The biggest earthquakes attained intensity V or even VI on the Mercalli scale at a distance around 35 km, and may have exceeded magnitude 5 on the Richter scale. The total lava production in the Northern Volcanic Zone during the last three centuries was 0.25-0.3 km3 in each rifting event excluding the Askja 1961 eruption which had an extrusion volume of 0.1 km3. -from Author