Experimental data of analogue models addressing the influence of oblique convergence and inheritance on sliver tectonics

Abstract

This dataset includes video sequences depicting the evolution in map view and lateral view of 7 analogue experiments studying mantle-scale subduction systems. The experiments are performed under a natural gravity field and are designed to understand the role of convergence obliquity on upper plate deformation and partitioning, with a particular emphasis on the role played by lithospheric inherited structures on the development of sliver tectonics.
All experiments were performed at the Laboratory of Tectonic modelling of the University of Rennes 1 (France). The experimental set-up corresponds to a lithosphere and sub-lithospheric upper mantle system. The lithospheric plates are simulated with PDMS silicone (Polydimethylsiloxane Silicone) with different viscosities and densities, and the upper mantle with glucose syrup. In particular, for the overriding plate, we simulate the presence of a weaker volcanic arc that can eventually be decoupled from the forearc by a pre-existing discontinuity. The materials are placed into a Plexiglas tank, where the impermeable bottom of the tank represents the 660 km discontinuity. The subduction is initiated by manually forcing the slab into the mantle and it then evolves under the combined effects of internal buoyancy forces (slab pull) and external boundary forces. The subducting plate is pushed toward the trench at a constant velocity of 1.5 cm/min while the overriding plate is maintained fixed during the duration of the experiments.
The evolution of the experiments is monitored by DSLR cameras (24 Mpx) taking pictures every 30 seconds at the top and on one side of the experiments. Pictures are then assembled into video-sequences. The scale bar, with black & white rectangles corresponds to 10 cm.
The set of experiments consists of one reference model (MODEL-01) with orthogonal convergence, and six models with oblique convergence (Table 1). Among these models, three do not embed a pre-existing lithospheric discontinuity in the overriding plate (MODEL-02, MODEL-03, and MODEL-04) while the three other (MODEL-05, MODEL-06, and MODEL-07) have such a discontinuity. For the models with oblique convergence, we vary the angle between the convergence direction and the trench from 80° (MODEL-02 and MODEL-05) to 60° (MODEL-03 and MODEL-06) and 50° (MODEL-04 and MODEL-07).
For details on the experimental set-up, and interpretation of the results, please refer to Suárez et al. (submitted to Tectonophysics) to which these data are supplementary material.

Authors

• Suárez, Rodrigo Javier;Instituto de Estudios Andinos (Universidad de Buenos Aires - CONICET), Buenos Aires, Argentina.
• Guillaume, Benjamin;Université de Rennes, CNRS, Géosciences Rennes, Géosciences Rennes, Rennes, France
• Martinod, Joseph;ISTerre, Université de Savoie Mont-Blanc, Le Bourget du Lac cedex, France
• Ghiglione, Matías;Instituto de Estudios Andinos (Universidad de Buenos Aires - CONICET), Buenos Aires, Argentina.
• Sue, Christian;Chrono-environnement, CNRS-UMR6249, Université de Franche-Comté, Besançon cedex, France
• Kermarrec, Jean-Jacques;Université de Rennes, CNRS, Géosciences Rennes, Géosciences Rennes, Rennes, France

Contact

• Suárez, Rodrigo Javier (PhD student) ; Instituto de Estudios Andinos (Universidad de Buenos Aires - CONICET), Buenos Aires, Argentina.;
• Guillaume, Benjamin (Assistant professor) ; University of Rennes, CNRS, Géosciences Rennes, UMR 6118, Rennes, France;

Contributors

Grmodel - Laboratoire de modélisation analogique Géosciences Rennes (CNRS-Rennes 1 University, France)

Keywords

Subduction experiments, Trench-oblique convergence, Analogue models, Sliver tectonics, Vorticity number, Strike-slip, Thrusting, Cenozoic times, Patagonian Andes, Inherited anisotropies, Lithospheric strain, Slab dip variations, PIVLab software, Trac-Trac software, SSPX software, Strain tensor, Subduction dynamics, Fold and thrust belt, Interplate friction, Strain partitioning, Shear force, Trench-parallel motion, Liquiñe-Ofqui fault system, Slab roll-back, Trench retreat, Nazca plate, Traiguén basin, Chile triple junction, EPOS, multi-scale laboratories, analogue models of geologic processes, property data of analogue modelling materials, analogue modelling results, software tools, deformation > ductile flow, tectonic process > subduction, Density, Viscosity, Digital Image Correlation (DIC) / Particle Image Velocimetry (PIV), Digital Image Correlation (DIC) / Particle Image Velocimetry (PIV) > Matlab code, Digital Image Correlation (DIC) / Particle Image Velocimetry (PIV) > PIVlab, Matlab (Mathworks), earth interior setting > mantle setting, tectonic setting > plate margin setting > subduction zone setting, fault, fault > strike-slip fault, trench, Golden syrup, Silicon/Silly putty/PDMS, SLR camera, Time lapse camera, Subduction box, Density, Digital Image Correlation (DIC) / Particle Image Velocimetry (PIV), Digital Image Correlation (DIC) / Particle Image Velocimetry (PIV) > Matlab code, Digital Image Correlation (DIC) / Particle Image Velocimetry (PIV) > PIVlab, Golden syrup, Matlab (Mathworks), SLR camera, Silicon/Silly putty/PDMS, Subduction box, Time lapse camera, Viscosity, deformation > ductile flow, earth interior setting > mantle setting, fault, fault > strike-slip fault, tectonic process > subduction, tectonic setting > plate margin setting > subduction zone setting, trench

GCMD Science Keywords

• EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > CRUSTAL MOTION
• EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > FAULT MOVEMENT
• EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > LITHOSPHERIC PLATE MOTION
• EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > PLATE BOUNDARIES
• EARTH SCIENCE > SOLID EARTH > TECTONICS > PLATE TECTONICS > STRAIN