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Mechanical test data of quartz sand, garnet sand, gypsum powder (plaster), kaolin and sand-plaster mixtures used as granular analogue materials in geoscience laboratory experiments

This dataset provides mechanical test data for quartz sand (“MAM1ST-300”, Sibelco, Mol, Belgium), gypsum powder (plaster; “Goldband”, Knauf), kaolin clay powder, garnet sand, and mixtures of quartz sand and gypsum powder, used at the Analogue Laboratory of the Department of Geography at the Vrije Universiteit Brussel, Brussels, Belgium, for simulating brittle rocks in the upper crust (Poppe et al., 2019). The measured properties are density ρ, tensile strength T0, shear strength σ, obtained by density measurements, ring-shear tests (RST; at Helmholtz Centre Potsdam GFZ, Germany), direct shear tests, traction tests (at University of Maine, Le Mans, France) and extension tests. The obtained tensile strengths and shear strengths reconstruct two-dimensional failure envelopes for each material. By fitting linear Coulomb and non-linear combined Griffith failure criteria to the characterised failure envelopes (Jaeger et al., 2007), the internal friction coefficient µC, Coulomb cohesion CC and Griffith cohesion CG are obtained. The influence of the material emplacement technique has been investigated in Poppe et al. (2021) to which this data set is supplementary, by repeat characterisation of the above physical parameters under three emplacement conditions, i.e. sieving, pouring (non-dried state) and compaction after pouring (oven-dried state). We find that densities of the materials and mixtures range from ~1600 kg.m³ (sieved) and ~1700 kg.m³ (compacted) for pure quartz sand to ~600 kg.m³ (poured) to ~900 kg.m³ (compacted) for pure plaster. Tensile strengths range from ~166 Pa (sand) to ~425 Pa (plaster). Velocity ring-shear tests on a 90 wt% quartz sand – 10 wt% plaster mixture show a minor shear rate-weakening of <2% per ten-fold increase in shear velocity. The materials show a behavior ranging from Mohr-Coulomb behavior for the materials with coarser grain size (sands) to combined Griffith-Mohr-Coulomb behavior for the powder materials (plaster, kaolin), with the sand-plaster mixtures occupying a spectrum between both end-members. Peak friction coefficients range from ~0.5 (sand) to ~0.6 (plaster) with a maximum of ~0.9 (80:20 wt% sand:plaster), peak Coulomb cohesions range from 13 Pa (sand) to 248 Pa (plaster), peak Griffith cohesions range from ~10 Pa (sand) to ~425 Pa (plaster).

Geological data from the Western Afar Margin, East Africa

This dataset contains geological data from the Western Afar Margin (WAM) in East Africa. These in-clude (reprocessed) earthquake data from previously published surveys and publically accessible databases (Keir et al. 2006, 2009; Ebinger et al 2008; Belachew et al. 2011; Illsley-Kemp et al. 2018a, b and the GCMT Project 2019), which form the basis for Seismic Moment Release (SMR) mapping as well as and tectonic stress analysis, revealing the location and intensity of ongoing deformation, as well as the direction of current extension, respectively. In addition, we present various large-scale maps of the WAM, depicting faults, dikes and sedimentary basins as interpreted from topographic indicators.Field data (GPS locations, fault measurements, field book), acquired during two field campaigns in Ethiopia and Eritrea are included, as well as the kinematic interpretation of the field data using Wintensor software (Delvaux & Sperner 2003). These results are combined with previously published kinematic data from Eritrea and Ethiopia (i.e. the northernmost and southern segments of the WAM, studied by Chorowicz et al. 1999 and Sani et al. 2017), yielding the first coherent overview of (current) tectonic deformation covering the whole margin. Note that we also provide a field book with detailed descriptions of every outcrop, including photographs. Finally, we include unique borehole data from the Kobo graben area, based on well logs from irrigation projects kindly provided to us by local geologists during the Ethiopian field campaign (see section 2.5 and the acknowledgements) .Applications and interpretation of the data provided in this dataset can be found in Zwaan et al. (in review). For more description please refer to the data description. This data publication consists of 90 files: (digital) maps, GPS locations, tables, text and Wintensor files. A detailed overview of all files within this dataset is given in the List of Files.

Orientation data of lineations and foliations from the central Tauern Window (Austria)

This dataset contains orientation data for foliations (n=773) and lineations (n=512) from the central Tauern Window collected during fieldwork in the years 2016 to 2019. The data is distributed in the form of shapefiles for easy use with GIS software. It can be displayed conveniently using the symbology files that are also part of the dataset.

Script and case study dataset for numerical modelling of uplifted marine terrace sequences

Numerical model supporting the article: "Uplifted marine terraces at active margins: understanding the effects of sea reoccupation and coseismic uplift on uplift rate calculation. The forward numerical model reproduces the evolution of an uplifting margin subject to sea erosion. The age-mixing resulting from reoccupation and the likelihood of missing terraces along a staircase sequence increase the inaccuracy of terrace ages assigned through geometrical cross correlation; this may result in erroneous uplift rates and consequent misinterpretation of the uplift evolution. Further research is needed to explore whether vertical displacement reproducing the full seismic cycle, inclusive of both permanent and elastic deformation, and variable uplift rates, have a similar relevance in shaping the geometry of terrace sequences. The code provides the possibility to have steady uplift, i.e. aseismic and constant over time, or coseismic uplift, i.e. given by instantaneous vertical displacement, reproducing earthquakes. It is possible to define time intervals having different uplift rate values, or different uplift modes (aseismic and seismic periods), or vary the characteristic of the coseismic uplift, such as recurrence intervals and coseismic uplift displacement. The coseismic uplift can also be superimposed to a background uplift rate. All values can be of positive or negative sign. The user can define which variable values are saved in the model output, and these include parameters such as the terrace age and the reoccupation tracker. In the repository we include three sea level curves, but any other sea level curve provided by the user can be used to run the model. The parameter values used in the manuscript models are described in the Supplementary Information file of the manuscript. The data provided in txt format report data published by Saillard et al. (2011) and additional calculations, which have been used for the case study of the manuscript. The model scripts are written in Julia language and can be used to reproduce marine terraces formation at coastal margins subject to uplift. The scripts are organized as Github repository (https://github.com/albert-de-montserrat/LEM1D). Movies S1 to S8 provide a qualitative illustration of the terrace evolution under different uplift conditions.

COSC-2 operational report - Operational data sets

The Collisional Orogeny in the Scandinavian Caledonides (COSC) scientific drilling project focuses on mountain building processes in a major mid-Paleozoic orogen in western Scandinavia and its comparison with modern analogues. The transport and emplacement of subduction-related highgrade continent-ocean transition (COT) complexes onto the Baltoscandian platform and their influence on the underlying allochthons and basement is being studied in a section provided by two fully cored 2.5 km deep drill holes. These operational data sets concern the second drill site, COSC-2 (boreholes ICDP 5054-2-A and 5054-2-B), drilled from mid April to early August 2020. COSC-2 is located approximately 20 km eastsoutheast of COSC-1, close to the southern shore of Lake Liten between Järpen and Mörsil in Jämtland, Sweden. COSC-2 drilling started at a tectonostratigraphic level slightly below that at COSC-1’s total depth. It has sampled the Lower Allochthon, the main Caledonian décollement and the underlying basement of the Fennoscandian Shield, including its Neoproterozoic and possibly older sedimentary cover. COSC-2 A reached 2276 m driller's depth with nearly 100 % core recovery between 100 m and total depth. COSC-2 B, with a driller’s depth of 116 m, covers the uppermost part of the section that was not cored in COSC-2 A. The operational data sets include the drill core documentation from the drilling information system (mDIS), full round core scans, MSCL data sets, a preliminary core description and the geophysical downhole logging data that were acquired during and subsequent to the drilling operations. All downhole logs and core depth were subject to depth correction to a common depth master (cf. operational report for detailed information). The COSC-2 drill core is archived at the Core Repository for Scientific Drilling at the Federal Institute for Geosciences and Natural Resources (BGR), Wilhelmstr. 25–30, 13593 Berlin (Spandau), Germany.

A database of R-R-R triple junction analogue and numerical models

This dataset presents the raw data from two experimental series of analogue models and four numerical models performed to investigate Rift-Rift-Rift triple junction dynamics, supporting the modelling results described in the submitted paper. Numerical models were run in order to support the outcomes obtained from the analogue models. Our experimental series tested the case of a totally symmetric RRR junction (with rift branch angles trending at 120° and direction of stretching similarly trending at 120°; SY Series) or a less symmetric triple junction (with rift branches trending at 120° but with one of these experiencing orthogonal extension; OR Series), and testing the role of a single or two phases of extension coupled with effect of differential velocities between the three moving plates. An overview of the performed analogue and numerical 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) and Maestrelli et al. (2020). Numerical models were run with the finite element software ASPECT (e.g., Kronbichler et al., 2012; Heister et al., 2017; Rose et al., 2017).

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.

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