Report on Saunders (United Kingdom) — March 2004
Bulletin of the Global Volcanism Network, vol. 29, no. 3 (March 2004)
Managing Editor: Richard Wunderman..
Saunders (United Kingdom) A MODIS thermal alert on 7 May 2003 (no secondary confirmation)
Please cite this report as:
Global Volcanism Program, 2004. Report on Saunders (United Kingdom). In: Wunderman, R. (ed.), Bulletin of the Global Volcanism Network, 29:3. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN200403-390090.
57.8°S, 26.483°W; summit elev. 843 m
All times are local (unless otherwise noted)
The only previous report on the remote Michael volcano was in BGVN 28:02, which commented on a lava lake detected by satellite imagery over the period 1995-2002. A review of MODIS data for the period from that report (end 2002) to 16 March 2004 (UTC) reveals one thermal alert, on 7 May 2003 (UTC). No corroborative report is available, although previous alerts were interpreted as possibly representing lava lake activity.
Geologic Background. Saunders Island is a volcanic structure consisting of a large central edifice intersected by two seamount chains, as shown by bathymetric mapping (Leat et al., 2013). The young constructional Mount Michael stratovolcano dominates the glacier-covered island, while two submarine plateaus, Harpers Bank and Saunders Bank, extend north. The symmetrical Michael has a 500-m-wide summit crater and a remnant of a somma rim to the SE. Tephra layers visible in ice cliffs surrounding the island are evidence of recent eruptions. Ash clouds were reported from the summit crater in 1819, and an effusive eruption was inferred to have occurred from a N-flank fissure around the end of the 19th century and beginning of the 20th century. A low ice-free lava platform, Blackstone Plain, is located on the north coast, surrounding a group of former sea stacks. A cluster of parasitic cones on the SE flank, the Ashen Hills, appear to have been modified since 1820 (LeMasurier and Thomson, 1990). Vapor emission is frequently reported from the summit crater. Recent AVHRR and MODIS satellite imagery has revealed evidence for lava lake activity in the summit crater.
Information Contacts: Rob Wright, Luke Flynn, and Eric Pilger; MODIS Thermal Alert System, Hawaii Institute of Geophysics and Planetology (HIGP), School of Ocean and Earth Science and Technology, University of Hawaii at Manoa (URL: http://modis.higp.hawaii.edu/).