HR: 11:20h
AN: V42A-05    [Abstracts]
TI: Non Destructive High-Resolution 3D Investigation of Vesicle Textures in Pumice and Scoria by Synchrotron X-Ray Computed Microtomography
AU: * Polacci, M
EM: polacci@ct.ingv.it
AF: Istituto Nazionale di Geofisica e Vulcanologia-sezione di Catania, Piazza Roma 2, Catania, 95123 Italy
AU: Baker, D
EM: donb@eps.mcgill.ca
AF: McGill University, 3450 rue University, Montreal, H3A 2A7 Canada
AU: Mancini, L
EM: lucia.mancini@elettra.trieste.it
AF: SYRMEP Group Sincrotrone Trieste S.C.p.A. , S.S. 14, km 163,5 in Area Science Park, Basovizza, 34012 Italy
AU: Tromba, G
EM: tromba@elettra.trieste.it
AF: SYRMEP Group Sincrotrone Trieste S.C.p.A. , S.S. 14, km 163,5 in Area Science Park, Basovizza, 34012 Italy
AU: Zanini, F
EM: zanini@elettra.trieste.it
AF: SYRMEP Group Sincrotrone Trieste S.C.p.A. , S.S. 14, km 163,5 in Area Science Park, Basovizza, 34012 Italy
AB: High resolution X-ray computed microtomography was applied to investigate the 3D structure of pyroclastic material from different active, explosive, hazardous volcanic areas. The experiments were performed at the SYRMEP beamline of the ELETTRA synchrotron radiation facility in Trieste (Italy). The 2D image slices resulting from tomography of selected pumice and scoria samples were transformed into volume renderings via specific tomographic software. The reconstructed volumes allowed us to test the applicability of this technique, novel in the field of volcanology, to volcanic specimens with different textural characteristics. The use of a third generation synchrotron radiation facility allowed optimal visualization of vesicle and crystal geometry in the reconstructed volume where conventional X-ray methods are strongly limited. The BLOB3D software package was used to accomplish quantitative descriptions of vesicle textures in terms of vesicularity, number density, volume and connectivity. The results exhibited complex patterns of the vesicle content, size, shape and distribution within the different pyroclasts and allowed us to track the degassing history of each single clast. With this preliminary study we demonstrate that computed microtomography is a feasible tool complementary to conventional microscopy methods for the full 3D textural characterization of volcanic clasts, and that it may be used to provide further constraints to models of degassing at active volcanoes.
DE: 8414 Eruption mechanisms and flow emplacement
DE: 8429 Lava rheology and morphology
DE: 8430 Volcanic gases
DE: 8434 Magma migration and fragmentation
SC: Volcanology, Geochemistry, Petrology [V]
MN: Fall Meeting 2005