HR: 0830h
AN: V51J-0409    [PDF]
TI: Linking Surface Activity to the Deep Volcanic Plumbing System: the CALIPSO Borehole Observatory Project on Montserrat
AU: Young, S R
EM: sry2@psu.edu
AF: Pennsylvania State University, College of Earth and Mineral Sciences, University Park, PA 16802 United States
AU: * Voight, B
EM: voight@ems.psu.edu
AF: Pennsylvania State University, College of Earth and Mineral Sciences, University Park, PA 16802 United States
AU: Mattioli, G S
EM: mattioli@uark.edu
AF: University of Arkansas, Department of Geosciences 113 Ozark Hall, Fayetteville, AR 72701 United States
AU: Linde, A T
EM: linde@dtm.ciw.edu
AF: Carnegie Institution of Washington, Department of Terrestrial Magnetism 5241 Broad Branch Road, NW, Washington, DC 20015 United States
AU: Sacks, I S
EM: sacks@dtm.ciw.edu
AF: Carnegie Institution of Washington, Department of Terrestrial Magnetism 5241 Broad Branch Road, NW, Washington, DC 20015 United States
AU: Malin, P E
EM: malin@duke.edu
AF: Duke University, Department of Earth and Ocean Sciences Box 90235, 27708, NC 27708 United States
AU: Shalev, E
EM: shalev@duke.edu
AF: Duke University, Department of Earth and Ocean Sciences Box 90235, 27708, NC 27708 United States
AU: Hidayat, D
EM: hidayat@essc.psu.edu
AF: Pennsylvania State University, College of Earth and Mineral Sciences, University Park, PA 16802 United States
AU: Elsworth, D
EM: elsworth@psu.edu
AF: Pennsylvania State University, College of Earth and Mineral Sciences, University Park, PA 16802 United States
AU: Sparks, R S
EM: steve.sparks@bristol.ac.uk
AF: University of Bristol, Department of Earth Sciences Queens Road, Bristol, BS8 1RJ United Kingdom
AU: Neuberg, J
EM: j.neuberg@earth.leeds.ac.uk
AF: University of Leeds, School of Earth Sciences, Leeds, LS2 9JT United Kingdom
AU: Dunkley, P N
EM: pnd@bgs.ac.uk
AF: Montserrat Volcano Observatory, Flemings, Salem, 00000 Montserrat
AU: Norton, G E
EM: gill@mvo.ms
AF: Montserrat Volcano Observatory, Flemings, Salem, 00000 Montserrat
AU: Herd, R A
EM: richard@mvo.ms
AF: Montserrat Volcano Observatory, Flemings, Salem, 00000 Montserrat
AU: Edmonds, M
EM: marie@mvo.ms
AF: Montserrat Volcano Observatory, Flemings, Salem, 00000 Montserrat
AU: Thompson, G
EM: gtho@bgs.ac.uk
AF: Montserrat Volcano Observatory, Flemings, Salem, 00000 Montserrat
AU: Jolly, A
EM: aj@earth.leeds.ac.uk
AF: University of Leeds, School of Earth Sciences, Leeds, LS2 9JT United Kingdom
AU: Bass, V
EM: venus@mvo.ms
AF: Montserrat Volcano Observatory, Flemings, Salem, 00000 Montserrat
AB: The prolonged and ongoing volcanic activity at SoufriŠre Hills Volcano (SHV), Montserrat, provides a rare chance for collecting multi-stream monitoring data in support of volcano research. Conventional surface geophysical instrumentation and detailed observational and geochemical data have enabled the development of a good understanding of surface and near-surface physical processes controlling eruptive style and intensity at SHV. However, the geophysical character and behavior of the deeper plumbing system, including magma storage area(s) and deep recharge processes, are not well understood. Developing better models for the deep system will assist in providing timely warning of large events or changes in eruptive style, and may also provide some clues as to the likely duration of the eruption. Installation of seismic and deformational monitoring instrumentation at depth enables a significant increase in signal to noise ratio so that smaller signals can be recorded and more distant sites (and thus deeper investigation depth) utilized. A variety of cycle-lengths have been noted during the eruption of SHV, and we hope that the new CALIPSO data stream will enable development of models in which cycles from a few hours to a few decades can be linked together in an integrated physical model. Cycle lengths of 7 to 14 weeks (depending on eruption rate and equating to the eruption of about 35 million cubic meters of magma) are likely to source from the shallower of the two upper crustal reservoirs indicated by geochemical evidence. The 30 to 35 year cycles (the fourth one of which marked the start of the current eruption) may relate to processes concerning input of basaltic magma to the deeper plumbing system. We also hope to document geophysical changes in the plumbing system induced by regional seismicity; many eastern Caribbean volcanoes (including SHV between 1933 and 1935 and in 1985) have demonstrated characteristics of unrest triggered or invigorated by regional tectonic earthquakes of Richter magnitude 5 and above. Events within the historical triggering threshold occur every few years; two such events have so far occurred since CALIPSO instrument installation (a Mw6.6 about 400km NE of Montserrat and a Mw5.7 about 150km NE of Montserrat). Both are at the lower end of historical triggering threshold parameters for magnitude and distance and neither produced measurable changes in macro-seismicity or ground deformation beneath SHV.
DE: 7280 Volcano seismology (8419)
DE: 8414 Eruption mechanisms
DE: 8419 Eruption monitoring (7280)
DE: 8434 Magma migration
DE: 8494 Instruments and techniques
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2003 Fall Meeting