Multi-year uplift and erosion rates of Makran marine terraces: Impacts on coastal geomorphology

Marine terraces with dominant E-W strikes are prominent geomorphological features along the Makran coast. The ongoing uplift of these terraces, initiated in the Pleistocene, has shaped the geomorphology and morphodynamics of the Makran coastal zone. Using radar interferometry with ENVISAT ASAR data and the SBAS model, multi-year (2003−2010) uplift and erosion rates for the Iranian and Pakistani Makran marine terraces were estimated. Results show heterogeneous uplift rates with spatial variation along the coast, independent of terrace elevation or geographic location. The varying activities of local normal faults are most probably responsible for these differences in uplift and erosion rates. The Iranian and Pakistani Makran marine terraces have comparable mean uplift rates of 0.37 mm/yr, consistent with millennial uplift rates recorded from absolute ages. The Lipar terrace in Iran and the Ormara terrace in Pakistan exhibit the highest mean uplift rates at 0.77 mm/yr. Notably, the Jabal-i-Mehdi terrace in Pakistan is the only one with a mean erosion rate (∼0.18 mm/yr) that surpasses the regional uplift rate. The uplift of the Makran terraces has also contributed to the development of diverse geomorphic features, including coastal sinuosity (peninsulas and embayments), horseshoe-shaped embayments, tombolos, river catchments, coastal sand colonies, and wave-cut sea caves and arches.