4.5 GPlate reconstructions
Relative plate motions induce corresponding regional strain into plates
near the plate boundary (Ledouzey, 1986; Heidbach et al., 2007; Zoback
& Zoback, 2007). Eastern Oman is located near the present-day
Arabia-India plate boundary, i.e., near the Owen Fracture Zone (Fournier
et al., 2008; DeMets et al., 2010; Fig. 1).
The ~N/S to NW/SE-oriented Eocene to Miocene compressive
structures deformed sedimentary rocks likely due to ~E/W
to NE/SW-directed shortening. A suitable geodynamic cause for this
shortening is the convergence history between the Arabian and Indian
plates as suggested by Fournier et al. (2006) and Gaina et al. (2015).
The latter authors suggested minor E/W-shortening between the Arabian
and Indian plates from 40 Ma to the present (their Fig. 7). We analyzed
the plate configurations of Arabia and India during the Cenozoic using
the GPlates software to develop the causal relationship.
In all our reconstructions, Arabia is anchored (fixed). We describe the
distance of India (near the present-day location of Karachi at
24°50ꞌN/66°40ꞌE) and the western tip of the 64 Ma isochron, as part of
the Indian Plate, with respect to Arabia (East of Sur:
22°29ꞌ30ꞌN/59°49ꞌE; Figs. 10-12). We calculated/measured the
E/W-component of distance of the two fix points between India and Arabia
at different times (distance between Karachi and Sur, and distance
between western tip of the 64 Ma isochron and Sur).