HR: 0800h
AN: G51A-0074    [Abstracts]
TI: Constraints on the geometry of the magma chamber of Mauna Loa volcano, Hawaii, from InSAR data
AU: * amelung, f
EM: amelung@rsmas.miami.edu
AU: Walter, T
EM: twalter@rsmas.miami.edu
AB: A period of inflation of Mauna Loa volcano has started in May 2002. Since the beginning of the inflation period the GPS network of the Hawaiian Volcano Observatory has detected a total shortening of ~25 cm of a baseline across the summit caldera. The inflation of the volcanic edifice is commonly explained by the intrusion of new magma into a shallow magma chamber. InSAR data derived from Radarsat imagery provide new constraints on the shallow magmatic system of the volcano. The InSAR data show changes in distance between the ground and the satellite at rates of ~5 cm/yr, depending on the SAR viewing geometry. We present models of the magmatic system to explain the observed surface deformation. The data can not be explained using commonly used models for volcanic inflation, such as point or ellipsoidal source models in an elastic half-space. We discuss alternative models using finite magma chambers that include the effects of the volcano topography.
DE: 8494 Instruments and techniques
DE: 8499 General or miscellaneous
DE: 3010 Gravity
SC: Geodesy [G]
MN: 2004 AGU Fall Meeting