Year: 2018
Type: article
Abstract: The kinematics of rift segment linkage in magmatic rifts remain debated.Strain patterns from Afar provide tests of current models of how segmented rifts grow in areas of incipient oceanic spreading.Here, we present a combined analysis of seismicity, interferometric synthetic aperture radar (InSAR), and GPS-derived strain rate maps to reveal that the plate-boundary linkage between the Red Sea and Gulf of Aden rifts of Afar is accommodated primarily by distributed extensional faulting.Large rotations about vertical axes predicted by bookshelf faulting models are not detected.Additionally, models of stress changes and seismicity induced by recent dikes provide poor fits to the observed time-space patterns of strike-slip earthquakes.Instead, we explain these features as resulting from rift-perpendicular shearing at the tips of spreading rifts where extension terminates against less stretched lithosphere.Our results demonstrate that distributed extension drives rift-perpendicular shearing, achieving plate-boundary linkage during incipient seafloor spreading.
Source: Geology
DOI: 10.1130/g45345.1
Language: English
Subfield: Geology
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: hybrid
Funders: National Science Foundation, National Aeronautics and Space Administration, Geological Society of America, Syracuse University, Geological Society of London, Strong, Sight Research UK, National Natural Science Foundation of China, Centre National de la Recherche Scientifique, Università di Pisa, Natural Environment Research Council
Awards: G1702601273, G245599828, G4336686537, G4602731179, G4946291142, Collaborative Research: Tectonic and Magmatic Processes during Early-Stage Rifting: an Integrated Study of Northern Lake Malawi, Africa, 基于InSAR/GPS的青藏高原地壳运动速度场及其变形模型研究, G8088449015, Rift volcanism: past, present and future, G8396517690, G851379641
OpenAlex ID: W2903397555