Parathethys Last Gasp in Central Asia and Late Oligocene Accelerated Uplift of the Pamirs

Cenozoic sedimentary rocks in the Tajik Basin record the history of retreat of the Paratethys from central Asia, tectonic activity within the surrounding Pamir and Tian Shan mountains, and Asian aridification. However, there remains a paucity of precise chronological constraints on the sequences from this region. Here we present integrated magnetostratigraphic, detrital zircon and monazite U-Pb geochronologic, and detrital apatite fission track thermochronologic data from the lower Cenozoic sedimentary sequences in the Tajik Basin. Our results indicate that the investigated sedimentary rocks were deposited between ~41 and 23.3 Ma, with a depositional hiatus between ~36 and 31 Ma. The last two marine regressions were dated at ~41 and ~37.4 Ma, respectively. Eolian sandy loess dominates the sequences from ~31 to ~25 Ma and gradually transitions to fluvial facies after ~25 Ma, consistent with late Oligocene to early Miocene acceleration of active deformation, uplift, and exhumation of the Pamirs.