1,410 research outputs found
Ediacaran Obduction of a Fore-Arc Ophiolite in SW Iberia: A Turning Point in the Evolving Geodynamic Setting of Peri- Gondwana
The Calzadilla Ophiolite is an ensemble of mafic and ultramafic rocks that represents the
transition between lower crust and upper mantle of a Cadomian (peri-Gondwanan) fore arc. Mapping and
structural analysis of the ophiolite demonstrates that it was obducted in latest Ediacaran times, because the
Ediacaran-Early Cambrian sedimentary series (Malcocinado Formation) discordantly covers it. The ophiolite
and emplacement-related structures are affected by Variscan deformation (Devonian-Carboniferous),
which includes SW verging overturned folds (D1) and thrusts (D2), upright folds (D3), extensional faults (D4),
and later faults (D5). These phases of deformation are explained in the context of Variscan tectonics as the
result of the progressive collision between Gondwana and Laurussia. Qualitative unstraining of Variscan
deformation reveals the primary geometry of Ediacaran-Cambrian structures and uncovers the generation of
east verging thrusts as responsible for the primary obduction of the Calzadilla Ophiolite. Restoration of
planar and linear structures associated with this event indicates an Ediacaran, east directed obduction of the
ophiolite, that is, emplacement of the Cadomian fore arc onto inner sections of the northern margin of
Gondwana. According to regional data, the obduction separates two extension-dominated stages in the
tectonic evolution of the African margin of northern Gondwana preserved in southern Europe. Preobduction
extension brought about the onset and widening of fore-arc and back-arc basins in the external part
of the continent, while postobduction extension facilitated the formation of extensional migmatitic domes,
an oceanward migration of back-arc spreading centers across peri-Gondwana, and the eventual opening
of a major basin such as the Rheic Ocean
Acoustic assessment and distribution of the main pelagic fish species in ICES Subdivision 9a South during the ECOCADIZ 2019-07 Spanish survey (July–August 2019).
Calidad en las justificaciones, uso de conceptos y consistencia entre datos e inferencias en la toma de decisiones
Acoustic assessment and distribution of anchovy, sardine and chub mackerel in ICES Subdivision 9a South during the ECOCADIZ 2019-07 Spanish survey (July-August 2019) with notes on the distribution of other pelagic species.
Protocolo de recuperación funcional de una lesión ligamentosa de rodilla en baloncesto
Will black holes eventually engulf the universe?
The Babichev-Dokuchaev-Eroshenko model for the accretion of dark energy onto
black holes has been extended to deal with black holes with non-static metrics.
The possibility that for an asymptotic observer a black hole with large mass
will rapidly increase and eventually engulf the Universe at a finite time in
the future has been studied by using reasonable values for astronomical
parameters. It is concluded that such a phenomenon is forbidden for all black
holes in quintessential cosmological models.Comment: 4 pages, RevTe
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