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Found 6 results.

Rheometric Analysis of Viscous Material Mixtures Used in the Tectonic Laboratory (TecLab) at Utrecht University, Netherlands

This dataset contains measurements of viscous and viscoelastic materials that are used for analogue modelling. Proper density and viscosity scaling of ductile layers in the crust and lithosphere, requires materials like Polydimethylsiloxane (PDMS), to be mixed with fillers and low viscoity silicone oils. Changing the filler content and filler material, the density, viscosity and power-law coefficient can be tuned according to the requirements. All materials contain a large amount of PDMS and all but one a small amount of an additional silicone oil. Adding plasticine or barium sulfate lead to shear thinning rheologies with power-law exponents of p<0.95. Adding corundum powder only has a minor effect on the power-law exponent. Some mixtures also have an apparent yield point but all are in the liquid state in the tested range. In general, the rheologies of the materials are very complex and in some cases strongly temperature dependent. However, in the narrow range of relevant strain rates, the behaviour is well defined by a power-law relation and thus found suitable for simulating ductile layers in crust and lithosphere.

Rheology of glucose syrup from the Tectonic Modelling Lab (TecLab) of the University of Bern (CH)

This dataset provides results from rheological tests of glucose syrup from two suppliers tested within the EPOS Multi-scale Laboratories (MSL) trans-national access (TNA) program 2019 at the Laboratory of Experimental Tectonics (LET), Univ. Roma TRE, Italy. Syrups Glucowheat 45/81 (GW45) and Glucowheat 60/79 (GW60) are produced by Blattmann Schweiz AG, Switzerland (2019 batch). Syrups GlucoSweet 44 (GS44) and GlucoSweet 62 (GS62) are produced by ADEA (Amidi Destrini ed Affini), Italy (2019 batch) . The four tested glucose syrups are labeled according to their DE value (dextrose equivalent value). For tested products from Blattmann Schweiz AG, the second number refers to the weight percentage of dry substance. Glucose syrup GS44 is used in full lithospheric scale analogue experiments at the Tectonic Modelling Lab (TecLab) at the University of Bern, Switzerland as a low-viscosity material simulating the asthenospheric mantle lithosphere to provide isostatic equilibration. The materials have been analyzed using a MCR301 Rheometer (Anton Paar) equipped with parallel plates geometry and rotational regime . To prevent the evaporation of the samples during the measurements, an external water-lock device has been used.

Rheometric data from rotational tests on magnetorheological silicones

This dataset provides rheometric data of magnetorheological (MR) silicones, i.e., mixtures of Polydimethylsiloxane (PDMS SGM36) and carbonyl iron powder. We characterized the viscous behavior of MR silicones at room temperature (i.e., T = 25 °C) as a function of carbonyl iron powder concentration and magnetic field strength using rotational (controlled shear rate and controlled shear stress) tests (Mezger, 2020). This dataset also provides the displacement and velocity fields of a simple experiment performed to test the use of magnetorheological silicones for experimental tectonics purposes. For a detailed description of sample preparation procedure, experimental setup and monitoring technique, as well as results interpretation, please refer to Brizzi et al. (under review).

Experimental data of analogue models of subduction investigating the interplays between mantle flow and slab pull

This dataset includes images depicting the evolution in map view and lateral view of 7 analogue experiments of subduction to better understand the interplays between slab pull and mantle flow at subduction zones. The experiments are performed under a natural gravity field and are designed to understand the influence of plate width and magnitude and direction of mantle flow on slab geometry, trench kinematics and shape, and superficial mantle deformation around the subduction zone. All experiments were performed at the Laboratory of Experimental Tectonics at the Università Roma Tre (Italy). The laboratory models consist of one viscous layer of silicone putty representing the subducting lithosphere resting on top of a tank filled with glucose syrup, representing the convective mantle. We impose a horizontal flow in the convective mantle by pushing at a constant velocity a piston in the glucose syrup below an intermediate horizontal plate representing the upper mantle-lower mantle discontinuity. The pictures show the time evolution of each experiment from the top (« top » folder) and lateral position (« lateral » folder) and were taken synchronously every 30 seconds, and downsampled to 5 minutes in this dataset. The entire set of pictures are available from the authors upon request. Model F14 is the reference model, without imposed mantle flow and with a slab width of 2000. Models F15 and F16 are models with 660 km and 4000 km, respectively. They allow us analyzing the effect of slab width in the absence of a background flow. Models F17 and F20 are models with slab width of 2000 km and a background flow coming from above the slab at velocities of 0.9 and 1.8 mm/min in the lab (corresponding to 0.9 and 2 cm/yr once scaled to nature), respectively. Models F24 and F26 are models with slab width of 2000 km and a background flow coming from below the slab at velocities of 0.9 and 1.8 mm/min in the lab (corresponding to 1.2 and 2.7 cm/yr once scaled to nature), respectively. For details on the experimental set-up, monitoring techniques and interpretation of the results, please refer to Guillaume et al. (2021) to which these data are supplementary material.

Rheology of viscous materials from the CNR-IGG Tectonic Modelling Laboratory at the University of Florence (Italy)

This dataset provides rheometric data of three viscous materials used for centrifuge experiments at the Tectonic Modelling Laboratory of CNR-IGG at the Earth Sciences Department of the University of Florence (Italy). The first material, PP45, is a mixture of a silicone (Polydimethylsiloxane or PDMS SGM36) and plasticine (Giotto Pongo). The PDMS is produced by Dow Corning and its characteristics are described by e.g. Rudolf et al. 2016a,b). Giotto Pongo is produced by FILA (Italy). Both components are mixed following a weight ratio of 100:45, and the final mixture has a density of 1520 kg m3. The second material, SCA705 is a mixture of Dow Corning 3179 putty, mixed with fine corundum sand and oleic acid with a weight ratio of 100:70:05 and a resulting density of 1660 kg m3. The final material, SCA7020 consists of the same components as SCA705, but with a slightly higher oleic acid content reflected in the weight ratio of 100:70:20. The mixture’s density is 1620 kg m3. The material samples have been analyzed in the Helmholtz Laboratory for Tectonic Modelling (HelTec) at GFZ German Research Centre for Geosciences in Potsdam using an Anton Paar Physica MCR 301 rheometer in a plate-plate configuration at room temperature (20˚C). Rotational (controlled shear rate) tests with shear rates varying from 10-4 to 1 s-1 were performed. Additional temperature tests were run with shear rates between 10-2 to 10-1 s-1 for a temperature range between 15 and 30˚C. According to our rheometric analysis, the materials all exhibit shear thinning behavior, with high power law exponents (n-number) for strain rates below 10-2s-1, while power law exponents are lower above that threshold.For PP45, the respective n-numbers are 4.8 and 2.6, for SCA705 6.7 and 1.5, and for SCA7020 9.1 and 2.0. The temperature tests show decreasing viscosities with increasing temperatures with rates of -3.8, -1.4 and -1.9% per ˚K for PP45, SCA705 and SCA7020, respectively. An application of the materials tested can be found in Zwaan et al. (2020).

Data supplement to: New analogue materials for nonlinear lithosphere rheology, with an application to slab break-off

This dataset provides strain and strain rate data on mixtures of plasticine, silicone oils and iron powder that has been used in slab break-of analogue experiments in the Tectonic Laboratory (TecLab) at Utrecht University (NL) as an analogue for viscously deforming lithosphere. The materials have been analyzed in a creep and recovery test, applying a parallel plate setup using an AR-G2 rheometer (by TA Instruments).The materials can in general be described as viscoelastic materials with a power-law rheology (see previous work on plasticine-silicone polymer mixtures Weijermars [1986], Sokoutis [1987], Boutelier et al. [2008]). For a couple of the tested materials we find a complementary Newtonian behavior at the low end of the tested stress levels, with a transition to power-law behavior at increasing stress. Furthermore, the materials exhibit elastic and anelastic (recoverable) deformation. The corresponding paper (Broerse et al., 2018) describes the rheology, while this supplement describes the raw data and important details of the measurement setup. The raw data concerns mostly (uncorrected) strain and strain rate data. The rheometry has been performed at the Advanced Soft Matter group at the Department of Chemical Engineering, Delft University of Technology, The Netherlands.

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