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Three-dimensional P-wave velocity structure of Mt. Etna, Italy

A. Villasenor·H.M. Benz·L. Filippi·G. De Luca·R. Scarpa·G. Patane·S. Vinciguerra
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Abstract

The three-dimensional P -wave velocity structure of Mt. Etna is determined to depths of 15 km by tomographic inversion of first arrival times from local earthquakes recorded by a network of 29 permanent and temporary seismographs. Results show a near-vertical low-velocity zone that extends from beneath the central craters to a depth of 10 km. This low-velocity region is coincident with a band of steeply-dipping seismicity, suggesting a magmatic conduit that feeds the summit eruptions. The most prominent structure is an approximately 8-km-diameter high-velocity body located between 2 and 12 km depth below the southeast flank of the volcano. This high-velocity body is interpreted as a remnant mafic intrusion that is an important structural feature influencing both volcanism and east flank slope stability and faulting.

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A. Villasenor, H.M. Benz, L. Filippi, G. De Luca, R. Scarpa, G. Patane, S. Vinciguerra. 1998. Three-dimensional P-wave velocity structure of Mt. Etna, Italy. https://doi.org/10.1029/98gl01240

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