Cenozoic epeirogeny of the Arabian Peninsula from drainage modeling

Abstract

It is generally accepted that the Arabian Peninsula has been uplifted by subcrustal processes.Positive residual depth anomalies from oceanic crust in the Red Sea and in the Gulf of Aden suggest that a region surrounding this peninsula is dynamically supported. Admittance calculations, surface wave tomography studies, and receiver function analyses all imply that regional topography is generated and maintained by some combination of mantle convective circulation and lithospheric thickness changes. Despite these significant advances, the spatial and temporal uplift rate history of the Arabian Peninsula is not well known. Here we show that a regional uplift rate history can be obtained by jointly inverting 225 longitudinal river profiles that drain this peninsula. Our strategy assumes that shapes of individual river profiles are controlled by uplift rate history and moderated by erosional processes. We used local measurements of incision rate to calibrate the relevant erosional parameters. In our inverse algorithm, uplift rate is permitted to vary smoothly as a function of space and time but upstream drainage area remains invariant. We also assume that knickzone migration is not lithologically controlled. Implications of these important assumptions have been investigated. Our results suggest that the Arabian Peninsula underwent two phases of asymmetric uplift during the last 20-30 Ma at rates of 0.05-0.1 mm a 21 . The southwestern flank of the peninsula has been uplifted by 1.5-2.5 km. Regional stratigraphic constraints, the age and composition of volcanism, paleosol formation, incised peneplains, emergent marine terraces, and thermochronometric measurements corroborate our calculated patterns of uplift. Progressive development of three domal swells along the western margin of the peninsula is consistent with localized upwelling of hot asthenospheric mantle.

Neogene Uplift and Magmatism of Anatolia: Insights From Drainage Analysis and Basaltic Geochemistry

“…Faccenna et al () invoke material upwelling beneath Afar and spreading laterally beneath Arabia and Anatolia to explain a range of regional observations. Wilson et al () analyze drainage networks and patterns of basaltic magmatism in Arabia, and describe a northward progression of uplift and magmatism throughout Cenozoic times consistent with the movement of asthenospheric thermal anomalies. Lateral displacement of hot plume material from beneath Afar would therefore appear to be a plausible mechanism for generating elevated asthenospheric temperatures beneath Anatolia.…”

Spatial and temporal uplift history of South America from calibrated drainage analysis

“…[] and Wilson et al . [] show that misfit between observed and calculated river profiles varies weakly with A since it is taken to a fractional power (i.e., m ). Recovered uplift rate histories remain essentially unchanged when precipitation rate varies with a periodicity of less than several million years.…”

Experimental migration of knickpoints: influence of style of base-level fall and bed lithology

“…This militates against assuming that the retreat rate of knickpoints is constant over varying bedrock lithologies. Future studies investigating uplift history through inverse modeling should therefore integrate a lithological term (see Wilson et al, 2014) to simulate knickpoint or knickzone retreat rate. Surprisingly, our 1-D experiments show that base-level variation, a key parameter studied in erosion /deposition systems, is not encoded by knickpoint height, i.e., H p .…”