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Figs. 6.28 and 6.29
Magnitude of the angular
acceleration vector ( blue
line ) and variations of
angular velocity ( red line )
for central Africa and
Australia since the late
Triassic (230 Ma)
in the central Atlantic. It is interesting to note
that the time interval of this event does not
overlap with the first episode of magmatism
in the New England seamounts chain, which is
103 Ma (Duncan 1984 ). Therefore, it is not
possible in this case to associate the lithospheric
traction with mantle plume magmatism. A
paleotectonic reconstruction at 154 Ma (M25 -
Kimmeridgian) is shown in Fig. 6.33 ,which
illustrates both the instantaneous velocity field
of the major continents at that time and the
0.20 ı Myr 2 clockwise acceleration field of
Laurasia. Undoubtedly, this event could have
triggered a phase of increased subduction in
the Tethys, associated with the obduction of the
Vardar ophiolites onto the Dinaric, Pannonian,
and Menderes-Tauride domains of east Europe
and Turkey (Schettino and Turco 2011 ).
Apart from the traction event that affected
Laurasia, the global velocity field shown in
Fig. 6.33 suggests a phase of relevant TPW,
associated with a clockwise rotation of the
lithosphere about an Equatorial pole. However,
this
is
only
a
possibility,
which
cannot
be
demonstrated merely
through the
observation
of
continental
lithosphere
velocity
fields.
The
next
probable
episode
of
traction
was
a
slowdown
of
Laurasia
and
India
between
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