Shear wave velocity variation across the Taupo Volcanic Zone, New Zealand, from receiver function inversion

S. Bannister; C.J. Bryan; H.M. Bibby

doi:10.1111/j.1365-246x.2004.02384.x

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Shear wave velocity variation across the Taupo Volcanic Zone, New Zealand, from receiver function inversion

S. Bannister·C.J. Bryan·H.M. Bibby

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Abstract

The Taupo Volcanic Zone (TVZ), New Zealand is a region characterized by very high magma eruption rates and extremely high heat flow, which is manifest in high-temperature geothermal waters. The shear wave velocity structure across the region is inferred using non-linear inversion of receiver functions, which were derived from teleseismic earthquake data. Results from the non-linear inversion, and from forward synthetic modelling, indicate low S velocities at ∼6–16 km depth near the Rotorua and Reporoa calderas. We infer these low-velocity layers to represent the presence of high-level bodies of partial melt associated with the volcanism. Receiver functions at other stations are complicated by reverberations associated with near-surface sedimentary layers. The receiver function data also indicate that the Moho lies between 25 and 30 km, deeper than the 15 ± 2 km depth previously inferred for the crust–mantle boundary beneath the TVZ.

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Geophysical Journal International Article

Source-reported bounding extent: -39.00211029922513° to -38.59970036588819° latitude; 175.67138671875° to 176.1383056640625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

S. Bannister, C.J. Bryan, H.M. Bibby. 2004. Shear wave velocity variation across the Taupo Volcanic Zone, New Zealand, from receiver function inversion. https://doi.org/10.1111/j.1365-246x.2004.02384.x

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