M. Ramsey and Kuhn, S., Department of Geology and Planetary Science, 200 SRCC Building, University of Pittsburgh, Pittsburgh, PA 15260

Thermal infrared (TIR) satellite remote sensing has played a key role in monitoring volcanic activity and characterizing several fundamental volcanic activity parameters. The Advanced Spaceborne Thermal Emission Reflectance Radiometer (ASTER) is the first high resolution multi-spectral TIR imager in orbit and has been ideal for discerning the physical variations on the surface of active lava domes. These data provide a quantitative means of estimating surface composition, texture, temperature, and gas flux. A time series of ASTER data spanning four years of the Soufrihre Hills eruption have been analyzed using a newly-developed multistage retrieval algorithm. Designed to extract data from a non-isothermal, spectrally-mixed pixel, this approach takes advantage of ASTER's multi-spectral TIR and coincident short wave infrared (SWIR) data. The results show the presence of moderate to vigorous thermal infrared anomalies centered on the dome and pyroclastic flows, and changing surface texture/bulk composition with time. These results were also compared against Montserrat Volcano Observatory weekly reports from 1999 to 2004. The reports were ingested into a multi-parameter database, which highlights specific volcanic activity such as dome growth, pyroclastic flow intensity, rock fall, etc. It also serves as a unique cross-reference for the interpretation of the space-borne data versus observable trends in the volcanic activity types. This work provides a better understanding of the potential of ASTER data by leveraging its multi-wavelength capability to recover data normally lost due to limited spatial resolution or detector saturation. Results are applicable to any active dome-forming eruption that has multi-temporal ASTER data coverage.

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Submitted: IAVCEI General Assembly, Pucón, Chile
Date: November 14 - 19, 2004