HR: 1340h
AN: V33C-1479    [Abstracts]
TI: Detecting small geothermal features at Northern Pacific volcanoes with ASTER thermal infrared data
AU: * Wessels, R
EM: rwessels@usgs.gov
AF: U.S. Geological Survey, Alaska Volcano Observatory, 4200 University Dr., Anchorage, AK 99508 United States
AU: Senyukov, S
EM: ssl@emsd.iks.ru
AF: Kamchatkan Experimental-Methodical Seismological Department (KEMSD), Geophysical Service Russian Academy of Science, Petropavlovsk-Kamcha, 683006 Russian Federation
AU: Tranbenkova, A
EM: fsagt1@uaf.edu
AF: Institute of Volcanology and Seismology, Far East Division Russian Academy of Science, Petropavlovsk-Kamcha, 683006 Russian Federation
AU: Ramsey, M S
EM: ramsey@ivis.eps.pitt.edu
AF: University of Pittsburgh, Department of Geology and Planetary Science, Pittsburgh, PA 15260 United States
AU: Schneider, D J
EM: dschneider@usgs.gov
AF: U.S. Geological Survey, Alaska Volcano Observatory, 4200 University Dr., Anchorage, AK 99508 United States
AB: The Alaska Volcano Observatory (AVO) and the Kamchatkan Volcanic Eruption Response Team (KVERT) monitor the eruptive state of volcanoes throughout the Aleutian, Kamchatkan, and Kurile arcs. This is accomplished in part by analyzing thermal infrared (TIR) data from the Advanced Very High Resolution Radiometer (AVHRR) and Moderate-resolution Imaging Spectroradiometer (MODIS) sensors at least twice per day for major thermal anomalies. The AVHRR and MODIS 1-km spatial resolution data have been very useful for detecting large and/or high-temperature thermal signatures such as Strombolian activity as well as lava and pyroclastic flows. Such anomalies commonly indicate a major eruptive event is in progress. However, in order to observe and quantify small and/or lower temperature thermal features such as fumaroles and lava domes, higher spatial resolution data with better radiometric and spectral resolution are required. We have reviewed 2600 available night and day time TIR scenes acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) over the volcanoes of the northern Pacific. The current archive spans from March, 2000 to present. ASTER is the only instrument that routinely acquires high spatial resolution (30 - 90 m) night time data over volcanic targets. These data sets typically contain 5 TIR (8-12 microns) with 90 meter spatial resolution and 6 shortwave infrared (SWIR) bands (1-3 microns) with 30 meter spatial resolution. After the general survey of the volcanic arcs, we have focused our efforts on several targets. Mt. Hague, in the Emmons Lake complex on the Alaska Peninsula, has had mostly cloud-free ASTER observations for twenty night time TIR and six daytime TIR since August 2000. A small lake in the lower crater of Mt. Hague has had a history of appearing and disappearing over the last few years. The ASTER data combined with several recent field observations allow us to track the changes in lake area and associated temperatures. With more frequent observations, we hope to determine the mechanism of these changes. The 1975-76 craters and lava flows of New Tolbachik Volcano in central Kamchatka appear as persistent thermal features in clear night time ASTER TIR data with ASTER TIR temperatures as high as $22\deg$C. Handheld FLIR TIR images (~0.5m pixels) from August 2004 show temperatures $>$$176\deg$C on the lava flow and $>$$226\deg$C in the crater wall. Mutnovsky and Gorely Volcanoes in southern Kamchatka also have several persistent thermal features in the ASTER data from late 2001 until at least November 2003. These features correlate to a vigorous fumarole field and crater lakes. The Mutnovsky thermal features were also observed in AVHRR data by KEMSD in March, June, and July 2003. The goal of this work is to better detect changes in current volcano activity or precursors to new activity. Our ongoing survey of the ASTER TIR data has created a database of many small (<90 m) or low temperature (20 to $38\deg$C) thermal features at several volcanoes in the northern Pacific region. We will attempt to observe each of the identified features at least annually using ASTER data as it becomes available over each target.
DE: 8419 Eruption monitoring (7280)
DE: 8494 Instruments and techniques
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2004 AGU Fall Meeting