In:
Solid Earth, Copernicus GmbH, Vol. 10, No. 2 ( 2019-04-03), p. 447-462
Abstract:
Abstract. The nature of the Ionian Sea crust has been the subject
of scientific debate for more than 30 years, mainly because seismic imaging
of the deep crust and upper mantle of the Ionian Abyssal Plain (IAP) has not
been conclusive to date. The IAP is sandwiched between the Calabrian and
Hellenic subduction zones in the central Mediterranean. A NNE–SSW-oriented
131 km long seismic refraction and wide-angle reflection profile, consisting
of eight ocean bottom seismometers and hydrophones, was acquired in 2014.
The profile was designed to univocally confirm the proposed oceanic nature
of the IAP crust as a remnant of the Tethys and to confute its
interpretation as a strongly thinned part of the African continental crust.
A P-wave velocity model developed from travel-time forward modelling is
refined by gravimetric data and synthetic modelling of the seismic data. A
roughly 6–7 km thick crust with velocities ranging from 5.1 to 7.2 km s−1, top to bottom, can be traced throughout the IAP. In the vicinity of
the Medina seamounts at the southern IAP boundary, the crust thickens to
about 9 km and seismic velocities decrease to 6.8 km s−1 at the crust–mantle
boundary. The seismic velocity distribution and depth of the crust–mantle
boundary in the IAP document its oceanic nature and support the
interpretation of the IAP as a remnant of the Tethys lithosphere with the
Malta Escarpment as a transform margin and a Tethys opening in the NNW–SSE
direction.
Type of Medium:
Online Resource
ISSN:
1869-9529
DOI:
10.5194/se-10-447-2019
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2019
detail.hit.zdb_id:
2545676-3
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