Dataset Information

The Hindu Kush slab break-off as revealed by deep structure and crustal deformation.

ABSTRACT: Break-off of part of the down-going plate during continental collision occurs due to tensile stresses built-up between the deep and shallow slab, for which buoyancy is increased because of continental-crust subduction. Break-off governs the subsequent orogenic evolution but real-time observations are rare as it happens over geologically short times. Here we present a finite-frequency tomography, based on jointly inverted local and remote earthquakes, for the Hindu Kush in Afghanistan, where slab break-off is ongoing. We interpret our results as crustal subduction on top of a northwards-subducting Indian lithospheric slab, whose penetration depth increases along-strike while thinning and steepening. This implies that break-off is propagating laterally and that the highest lithospheric stretching rates occur during the final pinching-off. In the Hindu Kush crust, earthquakes and geodetic data show a transition from focused to distributed deformation, which we relate to a variable degree of crust-mantle coupling presumably associated with break-off at depth.

SUBMITTER: Kufner SK

PROVIDER: S-EPMC7966371 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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The Hindu Kush slab break-off as revealed by deep structure and crustal deformation.

Kufner Sofia-Katerina SK Kakar Najibullah N Bezada Maximiliano M Bloch Wasja W Metzger Sabrina S Yuan Xiaohui X Mechie James J Ratschbacher Lothar L Murodkulov Shokhruhk S Deng Zhiguo Z Schurr Bernd B

Nature communications 20210316 1

Break-off of part of the down-going plate during continental collision occurs due to tensile stresses built-up between the deep and shallow slab, for which buoyancy is increased because of continental-crust subduction. Break-off governs the subsequent orogenic evolution but real-time observations are rare as it happens over geologically short times. Here we present a finite-frequency tomography, based on jointly inverted local and remote earthquakes, for the Hindu Kush in Afghanistan, where slab ...[more]

PMID: 33727553

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Dataset Information

The Hindu Kush slab break-off as revealed by deep structure and crustal deformation.

Publications

The Hindu Kush slab break-off as revealed by deep structure and crustal deformation.

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