Present‐Day Motion of the Arabian Plate. Issue 3 (21st March 2022)

• Record Type: Journal Article
• Authors: Viltres, Renier; Jónsson, Sigurjón; Alothman, Abdulaziz O.; Liu, Shaozhuo; Leroy, Sylvie; Masson, Frédéric; Doubre, Cécile; Reilinger, Robert
• Is Part Of: Tectonics. Volume 41:Issue 3(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-03-21
• Subjects: GNSS -- Plate tectonics; Geology, Structural -- Periodicals; 551.8
• DOI: 10.1029/2021TC007013
• Languages: English
• ISSNs: 0278-7407

Abstract

Abstract: The present‐day motions in and around the Arabian plate involve a broad spectrum of tectonic processes including plate subduction, continental collision, seafloor spreading, intraplate magmatism, and continental transform faulting. Therefore, good constraints on the relative plate rates and directions, and on possible intraplate deformation, are crucial to assess the seismic hazard at the boundaries of the Arabian plate and areas within it. Here we combine GNSS‐derived velocities from 168 stations located on the Arabian plate with a regional kinematic block model to provide updated estimates of the present‐day motion and internal deformation of the plate. A single Euler pole at 50.93 ± 0.15°N, 353.91 ± 0.25°E with a rotation rate of 0.524 ± 0.001°/Ma explains well almost all the GNSS station velocities relative to the ITRF14 reference frame, confirming the large‐scale rigidity of the plate. Internal strain rates at the plate‐wide scale (∼0.4 nanostrain/yr) fall within the limits for stable plate interiors, indicating that differential motions are compensated for internally, which further supports the coherent rigid motion of the Arabian plate at present. At a smaller scale, however, we identified several areas within the plate that accommodate strain rates of up to ∼8 nanostrain/yr. Anthropogenic activity and possible subsurface magmatic activity near the western margin of the Arabian plate are likely responsible for the observed local internal deformation. Put together, our results show a remarkable level of stability for the Arabian lithosphere, which can withstand the long‐term load forces associated with active continental collision in the northeast and breakup to the southwest with minimal internal deformation. Plain Language Summary: Good knowledge of relative motions between tectonic plates is crucial for earthquake hazard assessments. In this study, we use new geodetic GNSS (also known as GPS) measurements from many stations on the Arabian Peninsula to provide updated information about the motion of the Arabian plate relative to its neighboring tectonic plates. The new GNSS velocities indicate that as a whole, the Arabian plate moves like a single block, resisting well the push and pull forces associated with plate boundary processes at its margins. However, when looking at smaller scales, several areas within the plate are deforming, with aquifer pressure changes due to groundwater pumping being the main cause of the deformation in most cases. Key Points: GNSS observations and kinematic block modeling confirm the large‐scale rigidity of the Arabian plate Localized internal deformation likely resulting from anthropogenic activity Arabian plate lithosphere is sufficiently strong to withstand active continental collision in the northeast and breakup to the southwest