Publication Date:
2017-04-04
Description:
Because of the close similarity of some Italian and Mediterranean
tectonic situations to the East Asia tectonics – arcs, trenches, Wadati-
Benioff zones, volcanic and seismic activities, and a typical horizontal
bending of the alleged lithospheric slab –, many clues are examined in
search of new interpretations of the Mediterranean geological and
observational evidence, with the aim of finding solutions that are
exportable to the problems of the circumpacific arc-trench zones.
The facts coming from surface geology, magmatism, geochemistry,
different method tomographies, etc., are at variance with the
alleged Africa-Eurasia convergence. The clues for rifting prevail over
those for compression, and many tectonic situations previously
interpreted as due to plate collisions, are associated to or mixed to
rifting evidence. The proposal is put forward that uprising of mantle
material wedges between two separating lithospheric plates could be
a new working hypothesis.
On an expanding Earth the region interposed between Eurasia
and Africa has always had a smaller latitudinal extension with
respect to the large Paleo Tethys and Neo Tethys appearing on constant-
radius paleogeographical reconstructions. It is then possible,
in the expanding Earth view, also to identify as phases of opening
the Paleo Tethys and Neo Tethys currently alleged ‘closure’, which
has added to the Proterozoic nuclei the Variscan and Alpine terranes
respectively. These phases and their orogens have to be considered
as extensional phases, and the added terranes of African provenance
(e.g. the Adriatic fragment) should be regarded as fragments left
behind as continental Africa moved away. In this sense, considering
the ongoing process of opening as having Proterozoic origin, it is
possible to speak of the Mediterranean as a slowly nascent ocean,
but also – paradoxically – as a very old ocean.
Description:
Published
Description:
129-147
Description:
open
Keywords:
Continental and oceanic deep structures,
;
Wadati-Benioff zones, expanding Earth.
;
04. Solid Earth::04.01. Earth Interior::04.01.02. Geological and geophysical evidences of deep processes
;
04. Solid Earth::04.07. Tectonophysics::04.07.02. Geodynamics
;
04. Solid Earth::04.07. Tectonophysics::04.07.04. Plate boundaries, motion, and tectonics
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
Format:
5190215 bytes
Format:
application/pdf
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