HR: 1330h
AN: T32A-0905    [PDF]
TI: Three Dimensional Slab Structure of the Izu-Bonin-Mariana Arc
AU: * Miller, M S
EM: meghansmiller@yahoo.com
AF: The Australian National University Research School of Earth Sciences, Mills Road, Canberra, ACT 0200 Australia
AU: Lister, G S
EM: glister@bigpond.com.au
AF: The Australian National University Research School of Earth Sciences, Mills Road, Canberra, ACT 0200 Australia
AB: Recent studies on slab structure in the northwest Pacific have imaged inconsistent geometries of the subducted ocean lithosphere along the plate margin. Below the Mariana arc portions of the subducted Pacific plate penetrate into the upper mantle vertically while in areas below the Izu-Bonin arc the slab appears to lie horizontally. This large variation in geometry is particularly well visualized in three dimensions using a combination of seismic tomography and earthquake data. One important feature that has been identified from this multidisciplinary approach of studying the three-dimensional structure and tectonic history of the northwest Pacific margin is a subhorizontal tear in the Pacific slab at the southern end of the Izu-Bonin arc. This visualization has inspired new tectonic reconstructions and insight into the evolution of the subducting Pacific plate and the development of its current geometry.
DE: 7200 SEISMOLOGY
DE: 8100 TECTONOPHYSICS
SC: Tectonophysics [T]
MN: 2003 Fall Meeting