Neogene to Quaternary uplift history along the passive margin of the northeastern Arabian Peninsula, eastern Al Hajar Mountains, Oman

摘要

This work explores the uplift history of the best exposed marine terraces in the northeastern Arabian Peninsula (eastern Al Hajar Mountains). A multidisciplinary approach was employed, including a topographic survey, C-14 dating, thin section studies, and scanning electron microscopy analyses. Six distinctive marine terraces with widths ranging from tenth of meters to kilometers and elevations from 5 to similar to 400 m were studied. These terraces record an along-strike heterogeneous uplift history, while they show temporally variable uplift rates ranging between 0.9 to 6.7 mm/yr, which correlates well with other published uplift rates of marine terraces of the eastern Arabian Peninsula. We attribute the variable uplift along strike of the terraces, to a combination of uplift mechanisms: (1) during early to mid-Miocene along deep-rooted reverse faults that bound large crustal-scale blocks, (2) Pliocene or post-Pliocene uplift on the outer wall of the forebulge of the lower Arabian Plate as it bends to enter the Zagros-Makran subduction zone, and (3) a possible slowdown of subduction for the past similar to 40 ka.