10.5880/fidgeo.2020.020 Zwaan, Frank Frank Zwaan 0000-0001-8226-2132 University of Florence, Florence, Italy University of Bern, Bern, Switzerland Corti, Giacomo Giacomo Corti 0000-0001-7399-4438 CNR Italian National Research Council, Italy Keir, Derek Derek Keir 0000-0001-8787-8446 University of Southampton, Southampton, UK University of Florence, Florence, Italy Sani, Federico Federico Sani 0000-0001-8832-1471 University of Florence, Florence, Italy GFZ Data Services 2020 EPOS Analogue modelling results multi-scale laboratories Rifting Passive margin antiform deformation > ductile flow deformation > folding deformation > fracturing depression EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > CRUSTAL MOTION > CRUSTAL MOTION DIRECTION EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > FAULT MOVEMENT > FAULT MOVEMENT DIRECTION EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > PLATE BOUNDARIES EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > STRAIN EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > STRESS flexure/buckle geologic process graben graben normal fault plateau rift valley rifting sedimentary process > deposition tectonic and structural features tectonic process > continental_breakup > rifting tectonic setting > extended terrane setting > continental rift setting tectonic setting > plate margin setting > active continental margin setting tectonic setting > plate spreading center setting Zwaan, Frank Frank Zwaan 0000-0001-8226-2132 University of Florence, Florence, Italy University of Bern, Bern, Switzerland Zwaan, Frank Frank Zwaan 0000-0001-8226-2132 University of Florence, Florence, Italy University of Bern, Bern, Switzerland Zwaan, Frank Frank Zwaan 0000-0001-8226-2132 University of Florence, Florence, Italy University of Bern, Bern, Switzerland Zwaan, Frank Frank Zwaan 0000-0001-8226-2132 University of Florence, Florence, Italy University of Bern, Bern, Switzerland Corti, Giacomo Giacomo Corti 0000-0001-7399-4438 CNR Italian National Research Council, Italy Corti, Giacomo Giacomo Corti 0000-0001-7399-4438 CNR Italian National Research Council, Italy Keir, Derek Derek Keir 0000-0001-8787-8446 University of Southampton, Southampton, UK University of Florence, Florence, Italy Sani, Federico Federico Sani 0000-0001-8832-1471 University of Florence, Florence, Italy Tectonics Modelling Laboratory (IGG-CNR, Italy) 5f7c8ccbe6dc7fa403b3f7c6041a76a8 IGG-CNR, Florence, Italy Zwaan, Frank University of Bern, Bern, Switzerland Corti, Giacomo CNR Italian National Research Council, Italy 2020-04-02 Dataset 10.1016/j.tecto.2020.228595 10.1016/j.jafrearsci.2019.103649 10.1029/2019TC006043 10.5880/fidgeo.2020.017 CC BY 4.0 This data set includes images and videos depicting the evolution of deformation and topography in 17 analogue experiments of passive margin development, to better understand the ongoing tec-tonics along the western margin of Afar, East Africa. The tectonic background that forms the basis for the experimental design is described in Zwaan et al. 2020a-d, and references therein. The ex-periments, in an enhanced gravity field in a large-capacity centrifuge, examined the influence of brittle layer thickness, strength contrast, syn-rift sedimentation and oblique extension on a brittle-viscous system with a strong and weak viscous domain.

All experiments were performed at the Tectonic Modelling Laboratory of the Istituto di Geoscience e Georisorse - Consiglio Nazionale delle Ricerche (CNR-IGG) and of the Earth Sciences Department of the University of Florence (CNR/UF). The brittle layer (sand) thickness ranged between 6 and 20 mm, the underlying viscous layer, split in a competent and weak domain (both viscous mixtures), was always 10 mm thick. Asymmetric extension was achieved by removing a 1.5 mm thick spacer at the side of the model at every time step, allowing the analogue materials to spread when en-hanced gravity was applied during a centrifuge run.

Differential stretching of the viscous material creates flexure and faulting in the overlying brittle layer. Total extension amounted to 10.5 mm over 7 intervals for Series 1 models that aimed at un-derstanding generic passive margin development in a generic orthogonal extension setting, where-as up to 16.5 mm of extension was applied for the additional Series 2 models aiming to reproduce the tectonic phases in Afar. In models involving sedimentation, sand was filled in at time steps 2, 4 and 6 (i.e. after 3, 6 and 9 mm of extension). Detailed descriptions of the experiments, monitoring techniques and tectonic interpretation of the model results are presented in Zwaan et al. (2020a).
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung http://doi.org/10.13039/501100001711 P2BEP2_178523 Early Postdoc Mobility Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung http://doi.org/10.13039/501100001711 2017P9AT72 PRIN2017