HR: 1330h
AN: V42B-0362    [PDF]
TI: Santiaguito Volcano, Guatemala: A Study of Vent Dynamics Over the Past 50 Years
AU: * Head, E M
EM: emhead@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences 1400 Townsend Drive, Houghton, MI 49931-1295 United States
AU: Dalton, M P
EM: mpdalton@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences 1400 Townsend Drive, Houghton, MI 49931-1295 United States
AU: Bluth, G J
EM: gbluth@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences 1400 Townsend Drive, Houghton, MI 49931-1295 United States
AU: Rose, W I
EM: raman@mtu.edu
AF: Michigan Technological University, Department of Geological and Mining Engineering and Sciences 1400 Townsend Drive, Houghton, MI 49931-1295 United States
AB: October 1902 marked one of the Earth's largest historic eruptions at Santa Maria volcano, Guatemala. Since 1922, volcanic dome extrusion has been occurring on the southwest flank of Santa Maria from the continuously active Santiaguito vent system. Dangerous activity including vertical ash eruptions, avalanches, lava flows, and pyroclastic flows has been persistent from Santiaguito, requiring observations of the volcano to be carried out from a distance. Consequently, our understanding of subsurface processes, such as the shape, size, and position of the magma body and conduit systems must be inferred by remote measurements. There may be a correlation at Santiaguito between the effects of subsurface conduit dynamics on summit vent morphology and subsequent volcanic activity. Our recent observations have identified the presence of a ring-shaped vent, approximately 150m wide, within the Santiaguito summit dome, which is thought to represent the surface expression of a series of fractures generated from the conduit at depth. Thus, a time series of surface observations of vent geometry and observations of volcanic activity could help constrain the near surface conduit evolution. An archive of aerial photos from 1947 to 2000, photographs of vent activity from 1969 to present, and 11 hours of digital video from 2002 and 2003 volcanic activity at Santiaguito will be analyzed to discover how these observations are related. The objective of this project will be to better understand the conduit evolution at Santiaguito volcano by documenting changes in vent morphology over the last 50 years and to correlate these findings with eruptive history. These results can be further correlated with gas, thermal, seismic, and other geophysical studies, calculations of dome volume and dome dimensions, and predictive modeling of Santiaguito's volcanic activity.
DE: 8400 VOLCANOLOGY
DE: 8414 Eruption mechanisms
DE: 8419 Eruption monitoring (7280)
DE: 8499 General or miscellaneous
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2003 Fall Meeting