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We present videos and figures from 22 scaled analogue models used to investigate the interactions between a density anomaly rising in the mantle and the lithosphere in a Newtonian system.
The experimental setup consists of a two layers viscous lithosphere-upper mantle system obtained by using silicone putty-glucose syrup in a tank sized 40 cm × 40 cm× 50 cm. Glucose syrup (i.e., mantle) is a Newtonian, low viscosity, high-density fluid while silicone putty (i.e., lithosphere) is a visco-elastic material that behaves in a quasi-Newtonian fashion. The mantle upwelling (i.e., plume head) is produced by a high viscosity, low-density silicone sphere with a constant radius (15 mm) rising through the mantle at an average rise velocity of ~2.6 mm/s. A side-view camera images the ascending path of the sphere, allowing to track the sphere location and compute its velocity. A top-view, 3-D scanner records the evolution of topography from which the lithospheric uplift rate is inferred. All details about the model set-up, modeling results and interpretation are detailed in Sembroni et al. (2017).
The additional material presented in this publication includes 2 tables, 5 figures, and 23 time-lapse movie. The rheological properties of materials used in each model are listed in Table 1.
Table 2 is an excel file where the raw data of the models are specified (i.e., bulge width, topography, and uplift rate). Such data have been obtained by the 3-D scanner and then processed by a MATLAB code.
Figure 1, Figure 2, Figure 3, Figure 4, Figure 5 represent the 2-D topography evolution of the bulge in each experiment. Images have been grouped by considering the different experimental setups (i.e., homogeneous continental lithosphere - Figure 1, homogeneous oceanic lithosphere - Figure 2, low viscous decoupling layer - Figure 3, intermediate viscous decoupling layer - Figure 4, high viscous decoupling layer - Figure 5). Such figures consist of topographic profiles extracted from the surface obtained by the 3-D scanner in four different time steps (red numbers in the figures). 22 side-view videos (from Movie 1 to Movie 22) show the progress of the models from the releasing to the impingement of the sphere beneath the plate. The velocity of the video has been accelerated by a factor of 7.
While, the first 22 movies show the evolution of the experiments, Movie 23 shows the mantle convective flow associated to the ascending path of the mantle upwelling. Such flow has been detected by tracking the bubbles inside the syrup. In this model, no lithosphere has been placed on top of the syrup.
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