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Figs. 6.30 and 6.31
Magnitude of the angular
acceleration vector ( blue
line ) and variations of
angular velocity ( red line )
for east Antarctica and
Pacific since the late
Triassic (230 Ma). Boxes
indicate possible events of
traction
132 Ma (M10 - Hauterivian) and 127 Ma
(M4 - Barremian) (Figs. 6.24 , 6.25 , 6.26 , 6.27 ).
However, in this instance lower magnitudes of
angular acceleration (respectively 0.14 and
0.17 ı Myr 2 ) were accompanied by locations
of either poles or antipoles of acceleration not
far from these continents. Consequently, the
effective accelerations were low and there is
more than one doubt that this time interval was
effectively a phase of accelerated motion for
these plates. Figure 6.34 shows a reconstruction
at 132 Ma (M10 - Hauterivian). It is interesting
to note that in this reconstruction both S. America
and Africa have negligible angular velocities.
The successive episode of non-equilibrium
kinematics occurred at 84 Ma (C34-C33
boundary, Santonian) and influenced once again
the motion of N. America, Eurasia, and India.
However, while the episode of accelerated motion
ended during C33n ( 78 Ma - Campanian) in
the case of N. America and Eurasia (Figs. 6.24 ,
6.25 , 6.26 , 6.27 ), India continued to increase
its velocity until C21 ( 48 Ma - Lutetian)
(Figs. 6.26 , 6.27 ). Furthermore, while the former
plates experienced modest increases of angular
velocity, respectively 0.14 and 0.07 ı Myr 2 ,
India accelerated northward by 0.29, 0.33, and
0.44 ı Myr 2
during three distinct pulses between
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