Publication Date:
2024-01-17
Description:
We have found a previously unreported later seismic phase in seismograms of European seismic stations from
intermediate-depth and deep earthquakes of the Southern Tyrrhenian subduction zone. We observe this phase at
stations from 6 to 9◦ from the epicentre, towards north. Only seismograms of earthquakes located in a welldefined region of the slab, in the depth range of 215–320 km, show the later x-phase. In this work, we
describe the nature and possible origin of this phase, and we provide a simple 2D model to explain the observed
arrival times. Our analyses reveal that the x-phase propagates downward in a high velocity layer, possibly
located within the deepest part of the slab. We suggest that this layer reveals the presence of the dense hydrous
magnesium silicate phase A, introduced from petrological laboratory experiments, inferred to carry water in the
upper mantle and predicted to be found in cold subduction zones.
Description:
Published
Description:
229919
Description:
OST1 Alla ricerca dei Motori Geodinamici
Description:
JCR Journal
Keywords:
Southern Tyrrhenian subduction zone
;
Mineral phase A
;
Intermediate and deep seismicity
;
Waveforms analyses
;
Later seismic arrival/phase
;
04.06. Seismology
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article