Ground-based thermal imaging of lava lakes at Erebus volcano, Antarctica

Mount Erebus, a large intraplate stratovolcano dominating Ross Island, Antarctica, hosts the world's only active phonolite lava lakes. The main manifestation of activity at Erebus volcano in December 2004 was as the presence of two convecting lava lakes within an inner crater. The long-lived Ray Lake, -1400 m(2) in area, was the site of up to 10 small Strombolian eruptions per day. A new but short-lived, similar to 1000-1200 m(2) lake formed at Werner vent in December 2004 sourced by lava flowing from a crater formed in 1993 by a phreatic eruption. We measured the radiative heat flux from the two lakes in December 2004 using a compact infrared (IR) imaging camera. Daily thermal IR surveys from the Main Crater rim provide images of the lava lake surface temperatures and identify sites of upwelling and clownwelling. The radiative heat outputs calculated for the Ray and Werner Lakes are 30-35 MW and 20 MW, respectively. We estimate that the magma flux needed to sustain the combined heat loss is similar to 250-710 kg s(-1), that the minimum volume of the magma reservoir is 2 km(3), and that the radius of the conduit feeding the Ray lake is similar to 2 m. (c) 2008 Elsevier B.V. All rights reserved.