The timing of the initial India-Asia collision and the mechanisms that led to the
eventual formation of the high (>5 km) Tibetan Plateau remain enigmatic. In this Review,
we describe the spatio-temporal distribution and geodynamic mechanisms of surface
uplift in the Tibetan Plateau, based on geologic and palaeo-altimetric constraints.
Localized mountain building was initiated during a Cretaceous microcontinent collision
event in central Tibet and ocean-continent convergence in southern Tibet. Geological
data indicate that India began colliding with Asian-affinity rocks 65-60 million years
ago (Ma). High-elevation (>4 km) east-west mountain belts were established in southern
and central Tibet by similar to 55 Ma and similar to 45 Ma, respectively. These mountain
belts were separated by <= 2 km elevation basins centred on the microcontinent suture
in central Tibet, until the basins were uplifted further between similar to 38 and
29 Ma. Basin uplift to >= 4 km elevation was delayed along the India-Asia suture zone
until similar to 20 Ma, along with that in northern Tibet. Delamination and break-off
of the subducted Indian and Asian lithosphere were the dominant mechanisms of surface
uplift, with spatial variations controlled by inherited lithospheric heterogeneities.
Future research should explore why surface uplift along suture zones - the loci of
the initial collision - was substantially delayed compared with the time of initial
collision.
