The oceanic nature of the African slab subducted under Peloponnesus: thin-layer resolution from multiscale analysis of teleseismic P-to-S converted waves

Abstract

International audienc

The fate of the downgoing oceanic plate: Insight from the Northern Cascadia subduction zone

“…Using this criterion, we obtain a conservative value for the depth-uncertainty of about ±2 km, which is increased to ±4 km for the deeper interfaces. Errors on the thickness of the layers can be slightly overestimated due to frequency (1 Hz) used in this study (Gesret et al, 2010). Also, as we used only the Ps conversion, our layer thickness can be slightly overestimated with respect to other RF studies in the same area which make use of both Ps and multiples phases (e.g.…”

“…1) is an ideal location to explore the evolution and metamorphism of the subducted oceanic plate. Along the west coast of North America the young (<10 Ma) Juan de Fuca plate is subducting at approximately 4 cm/year (Gordon et al, 1990). Images of the Cascadia subduction zone structure at depth are primarily based on detailed seismic observations using various methodologies, even though there is a lack of prevalent Wadati-Benioff zone seismicity.…”

Slab top dips resolved by teleseismic converted waves in the Hellenic subduction zone

“…From teleseismic P‐to‐S converted waves at interfaces with sharp velocity contrasts, the slab top and Moho, can be identified and located. We have illustrated that such interfaces with less than 10 km separation in depth can be resolved, and we have constrained consistently over several receivers in Peloponnesus such a thin low‐velocity layer (LVL) between the upper plate mantle and the slab mantle [ Gesret et al , 2010]. This is the typical thickness of oceanic crust and hence for the first time we documented that the slab under Peloponnesus is unambiguously made of oceanic lithosphere.…”

Seismic investigation of the transition from continental to oceanic subduction along the western Hellenic Subduction Zone

“…A variety of seismic studies have been undertaken in the past decades to image the Hellenic subduction zone. These include traveltime tomography [ Ligdas et al , 1990; Spakman et al , 1993; Papazachos and Nolet , 1997; Piromallo and Morelli , 2003; Schmid et al , 2006], marine reflection and refraction profiles [ Hirn et al , 1996; Mascle and Chaumillon , 1998; Clément et al , 2000; Bohnhoff et al , 2001; Kopf et al , 2003; Kokinou et al , 2003, 2005], receiver‐function analyses [ Knapmeyer and Harjes , 2000; Tiberi et al , 2001; Li et al , 2003; van der Meijde et al , 2003; Endrun et al , 2005; Sodoudi et al , 2006; Zhu et al , 2006; Gesret et al , 2010], surface‐wave dispersion [ Calcagnile et al , 1982; Martínez et al , 2001; Pasyanos and Walter , 2002; Meier et al , 2004; Bourova et al , 2005; Karagianni et al , 2005; Di Luccio and Pasyanos , 2007; Endrun et al , 2008], and seismic anisotropy measurements [ Hearn , 1999; Schmid et al , 2004]. Here, we review the results from these previous seismic studies, focusing on the insight they provide on the Moho of the overriding plate and subducting slab.…”