1. Ambient noise tomography of the Katmai volcanic area, Alaska.
- Author
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Bai, Tong, Nayak, Avinash, Thurber, Clifford, Zeng, Xiangfang, and Haney, Matthew
- Subjects
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TOMOGRAPHY , *NOISE , *GROUP velocity , *SURFACE waves (Seismic waves) , *MAGMAS - Abstract
We present an ambient noise tomographic study of the mid-crustal magmatic system in the Katmai area, Alaska. Using multi-component (vertical and radial) seismic records at 70 stations deployed at various times over 20 years, we construct corresponding cross-correlograms and extract ~1010 Rayleigh-wave dispersion curves in the periods between 2 and 30 s. These enable us to obtain corresponding group velocity maps and finally a 3-D shear-wave velocity model to a depth of 25 km. The most striking feature is a ~25 km wide low-velocity anomaly beneath the Katmai area at depths of approximately 10 to 20 km, which we interpret as a mid-crustal magma storage zone. Our study complements previous local-scale tomography studies that unveil small upper crustal reservoirs, revealing the likely deep magma source ultimately responsible for the 1912 Novarupta-Katmai eruption. • Conducted surface (Rayleigh) wave tomography with multicomponent ambient noise data in Katmai area. • Identified a ~ 25 km wide mid-crustal (10–20 km deep) low-velocity anomaly. • Potentially the deep magma source responsible for the 1912 Novarupta-Katmai eruption. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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