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Found 11 results.

A database of enhanced-gravity analogue models examining the influence of pre-existing fabrics on the evolution of oblique rift

This dataset shows the original data of a series of enhanced-gravity (centrifuge) analogue models, which were performed to test the influence of the pre-existing fabrics in the brittle upper crust on the evolution of structures resulting from oblique rifting. The obliquity of the rift (i.e., the angle between the rift axis and the direction of extension) was kept constant at 30° in all the models. The main variable of this experimental series was the orientation of the pre-existing fabrics (indicated as the angle between the trend of the fabric and the orthogonal to extension), which varied from 0° to 90° (i.e., from orthogonal to parallel to the extension direction). The inherited discontinuities were reproduced by cutting with a knife through the top brittle layer of models. An overview of the experimental series is shown in Table 1. In this dataset, four different data types are provided for further analysis: 1) Top-view photos of model deformation, taken at different time intervals and showing the deformation process of each model; they can be used to interpret the geometrical characteristics of rift-related faults; 2) Digital Elevation Models (DEMs) used to reconstruct the 3D deformation of the analogue models, allowing for quantitative analysis of the fault pattern. 3) Movies of model deformation, built from top-view photos, which help to visualize the evolution of model deformation; 4) Faults line-drawings to be used for statistical quantification of rift-related structures. Further information on the modelling strategy and setup can be found in the publication associated to this dataset and in Corti (2012), Philippon et al. (2015), Maestrelli et al. (2020), Molnar et al. (2020), Zwaan et al. (2021), Zou et al. (2023). Materials used to perform these enhanced-gravity analogue models were described in Montanari et al. (2017), Del Ventisette et al. (2019) and Zwaan et al. (2020).

A database of caldera collapse analogue models stretched under extensional conditions

This dataset presents the raw data from one experimental series (named CCEX, i.e., Caldera Collapse under regional Extension) of analogue models performed to investigate the process of caldera collapse followed by regional extension. Our experimental series tested the case of perfectly circular collapsed calderas afterward stretched under regional extensional conditions, that resulted in elongated calderas. The models are primarily intended to quantify the role of regional extension on the elongation of collapsed calderas observed in extensional settings, such as the East African Rift System. An overview of the performed analogue models is provided in Table 1. Analogue models have been analysed quantitatively by means of photogrammetric reconstruction of Digital Elevation Model (DEM) used for 3D quantification of the deformation, and top-view photo analysis for qualitative descriptions. The analogue materials used in the setup of these models are described in Montanari et al. (2017), Del Ventisette et al. (2019), Bonini et al., 2021 and Maestrelli et al. (2021a,b).

A database of analogue models testing the interaction between magmatic intrusion-related doming and caldera collapse

This dataset presents the raw data from one experimental series (named CCEX, i.e., Caldera Collapse under regional Extension) of analogue models performed to investigate the process of caldera collapse followed by regional extension. Our experimental series tested the case of perfectly circular collapsed calderas afterward stretched under regional extensional conditions, that resulted in elongated calderas. The models are primarily intended to quantify the role of regional extension on the elongation of collapsed calderas observed in extensional settings, such as the East African Rift System. An overview of the performed analogue models is provided in Table 1. Analogue models have been analysed quantitatively by means of photogrammetric reconstruction of Digital Elevation Model (DEM) used for 3D quantification of the deformation, and top-view photo analysis for qualitative descriptions. The analogue materials used in the setup of these models are described in Montanari et al. (2017), Del Ventisette et al. (2019), Bonini et al., 2021 and Maestrelli et al. (2021a,b).

Slide-Hold-Slide Data of Granular Materials Used In Analogue Modelling

This data set provides a series of experiments from ring-shear tests (RST) on various materials that are used at several laboratories worldwide. The data contains the results of slide-hold-slide tests and the processed outputs of standardized ring shear tester data from related publications. Additionally, microscopy images of the materials under plain and polarized light are provided. The time dependent restrengthening of the materials is quantified using slide-hold-slide tests. This restrengthening has implications on the reactivation potential of granular shear zones in analogue models. With the provided software we first analyze the experimental data and then compare the angles and stresses needed to reactivate normal faults in the materials. We find that while healing rates are low, the majority of samples can not reactivate normal faults that are generated through extension of an analogue model.

Laboratory model data from experiments on fragmenting analogue rock avalanches

This data set includes various laboratory model data derived from analogue rock avalanche experiments on the role of fragmentation on runout behavior. Detailed descriptions of the experiments and monitoring and analysis techniques can be found in Haug et al. (submitted) to which this data set is supplementary. The data presented here consist of movies showing key avalanche experiments and kinematic data characterizing the runout behavior derived from 157 experiments.

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

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.

Pictures, DEMs, and raw data relative to analogue accretionary wedges

This dataset includes raw data used in the paper by Reitano et al. (2022), focused on the effect of boundary conditions on the evolution of analogue accretionary wedges affected by both tectonics and surface processes; the paper also focuses on the balance between tectonics and surface processes as a function of the boundary conditions applied. These boundary conditions are convergence velocity and basal slope (i.e., the tilting toward the foreland imposed prior the experimental run). The experiments have been carried out at Laboratory of Experimental Tectonics (LET), University “Roma Tre” (Rome). Detailed descriptions of the experimental apparatus and experimental procedures implemented can be found in the paper to which this dataset refers. Here we present: • Pictures recording the evolution of the models. • GIFs showing time-lapses of models. • Raw DEMs of the models and Incision DEMs, used for extracting data later discusses in the paper.

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.

Supplement to: Scaling the Sand Box - Mechanical (Dis-) Similarities of Granular Materials and Brittle Rock

The dataset presented here contains the results of mechanical testing of two granular materials (quartz sand and glass micro beads) that are commonly used in analogue tectonic experiments. The data were acquired using a ring-shear tester RST-01.pc [Schulze, 1994]. Tests were performed at different normal loads ranging from 125 Pa to 4000 Pa and with eight to ten repetitions per normal load and material. The parameters measured are: rotation velocity, shear stress, normal load and sample dilation, all as a function of time. A detailed analysis and interpretation of the data can be found in the main article of [Ritter et al., 2016].The data were measured in the ring-shear tester RST-01.pc [Schulze, 1994, see below] at GFZ Potsdam’s analogue laboratory for tectonic modelling. All samples have been prepared and measured by the same person. Preparation was by sifting from a constant height of 30 cm into the shear cell. Tests were performed at different normal loads ranging from 125 Pa to 4000 Pa and with eight to ten repetitions per normal load and material. For normal loads below 500 Pa, the samples were pre-loaded by shortly increasing the normal load to 500 Pa and then resetting it to the desired value prior to the onset of deformation. This pre-loading was carried out for technical reasons. Preliminary tests at a normal load of 300 Pa have shown that this does not affect the strength.The data are presented as shear curves in tab-separated text files. The file names consist of (in this order) material, normal load and a running number. Each file contains one shear curve and consists of a header describing the individual measurements followed by a table with one column per parameter (read more in the dataset description pdf).References:Schulze, D. (1994) Entwicklung und Anwendung eines neuartigen Ringschergerätes, Aufbereitungstechnik, 35(10), 524–535.

GeoMod2008 materials benchmark: The axial test dataset

This dataset provides compaction data from axial testing on natural and artificial granular materials used for experimental simulation by the analogue geodynamic modelling community (21 sands and glass beads). The material samples have been collected community-wide and analysed at GFZ Potsdam in the framework of the GeoMod2008 conference benchmark initiative. The context of data collection, details of the material samples and measuring techniques as well as interpretation and discussion of results can be found in Klinkmüller et al. (2016) to which this dataset is supplement material.

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