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Input files for the 2-D cases of the ASPECT models of a mantle plume and csv files for all output timesteps in Tables B1 and B2

In order to understand the difference between high temperature drop across the mantle's basal thermal boundary layer and much lower plume excess temperatures we evaluated computations with ASPECT. Some of them are published in the Ph.D. thesis of Poulami Roy, some others in previous work. Hence here we only include those models that are not published elsewhere. We also provide the routine to extract maximum and average plume temperatures versus depth. Our results show reduced excess temperatures, if plumes are more sheet-like, similar to 2-D models, or temperature at their source depth is less than at the CMB, for example if they are sourced on top of thermochemical piles. Excess temperatures are further reduced when averaged over the plume conduit or melting region. We provide here the prm files and required input files for the Aspect 2-D cases shown in Figures 2 and 3, which are the only cases that are neither included in Steinberger et al. (2023) nor in the Ph.D. thesis of Poulami Roy (2024). Figure 2 is computed with matteo_4.prm; in this case, the initial temperature is in initial_temp_ascii_2, prescribed (zero) surface velocitites are in vel-top-zero Figure 3 is computed with matteo_14.prm; in this case, the initial temperature is in in initial_temp_ascii_4b. In both cases, radial_visc_simple.txt is the radial viscosity structure corresponding to adiabatic temperatures, and the file temp-viscosity-prefactor.txt specifies the lateral viscosity variations due to temperature variations. We also provide the Routine post_processing_matteo_10km.py for extracting plume temperatures versus depth, written by Matteo Jopke. Furthermore, we provide csv files for all time steps listed in Tables B1 and B2 and shown in Figures 5-7 of the paper. These data have been used to compute plume temperatures and anomalous mass fluxes, in order to address the question posed in the title of the paper. Files are grouped according to model runs into tar files with the same name. The tables are also provided in the Appendix of this data description. The model files are grouped in .tar files according to the model types: single_plume.tar, 2_10.tar; 2.5_2_10.tar; no_slap.tar)

Supplementary material for analogue experiments on the impact of the lithosphere on dynamic topography

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.

ASPECT models of a mantle plume under West Antarctica

In order to test the feasibility of density and viscosity models suitable to explain geoid and dynamic topography in West Antarctica, we perform computations of a thermal plume that enters at the base of a cartesian box corresponding to a region in the upper mantle, as well as some whole-mantle thermal plume models, as well as some instantaneous disk models, with ASPECT. The plume models have typically a narrow conduit and the plume tends to only become wider as it spreads beneath the lithosphere, typically shallower than ~300 km. These results are most consistent with a shallow disk model with reduced uppermost mantle viscosity, hence providing further support for such low viscosities beneath West Antarctica. The data are a supplement to the following article: Steinberger, B., Grasnick, M.-L. & Ludwig, R., Exploring the Origin of Geoid Low and Topography High in West Antarctica: Insights from Density Anomalies and Mantle Convection Models, Tektonika, https://doi.org/10.55575/tektonika2023.1.2.35

Dataset for numerical modeling to investigate conditions leading to single- or multi-slab plume-induced subduction initiation

The data are the numerical modeling results to investigate plume-induced subduction initation on which the figures of the paper "Plume-induced subduction initiation: single- or multi-slab subduction?" by Baes, Sobolev, Gerya and Brune are based. Detailed description on how they are obtained is given in that article (Baes et al., 2020).The naming of the files is based on the number of figures in the paper. Each zipped file contains input files (init.t3c and mode.t3c) and output files (*.vtr).

Ruthenium and Tungsten isotopic composition of ocean island basalts and refrence materials

The dataset includes Ruthenium and Tungsten isotope data for mafic to ultramafic lava associated with the Hawaii, Réunion, Galápagos and Iceland plume systems. The data is supplemented by Ru isotope data for reference materials (OREAS 684) picrite derived from the upper mantle (Gönnern Quarry, Hessia) lherzolite preidotites (Eifel) and Eoarchean dunites (Isua, Greenland). The data are supplementary to: Messling, Nils; Willbold, Matthias; Kallas, Leander; Elliott, Tim; Fitton, J. Godfrey; Müller, Thomas; Geist, Dennis (submitted) Core leakage revealed by Ru and W isotope systematics in ocean island basalts. Submitted to Nature

3D lithospheric structure of the Caribbean and north South American Plates and Rotation Files of Kinematic Reconstructions back to 90 Ma of the Caribbean Large Igneous Plateau

We are providing the geophysical data used to develop a gravity validated 3D lithospheric configuration of the Caribbean and north South American plates. The sources of these data are described in Section 4 of this README. Republication of subsets of these data are with permission of the authors or allowed by the licences of the input data. This data repository contains the lithospheric layers of the gravity validated 3D structural and density model of the Caribbean and north South American plates. In this model, the integration of different publicly available geophysical datasets was made, after an interpolation to a homogeneous spatial resolution of 25 km was performed. The data repository also contains the average density of the crystalline crust obtained after forward modelling the gravity anomalies. Additionally, the rotation files of the GPlates reconstructions of the Caribbean Large Igneous Plateau (CLIP) back to 90 Ma are included. This kinematic analysis was based on different reconstructions previously published by other authors. Further information and citations are given on the README file associated to this data repository.

Yellowstone hotspot motion and plume conduits

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Upward mantle flow from novel seismic observations (UPFLOW)

The goal of the UPFLOW project is to develop new high-resolution seismic imaging approaches along with new data collection, and to use them to constrain upward flow in unprecedented detail. We conducted a large off-shore experiment in the Azores-Madeira-Canary Islands region, which is a unique natural laboratory with multiple upwellings that are poorly understood in general. UPFLOW deployed and recovered 49 ocean bottom seismometers (OBSs) in a ~1,000×2,000 km2 area in the Azores-Madeira-Canary Islands region starting in July 2021 for ~13 months, with an average spacing of ~150-200 km. The seismic deployment and recovery involved institutions from five different countries: Portugal (IPMA, IDL, Univ. of Lisbon, ISEL), Ireland (DIAS), UK (UCL), Spain (ROA) and Germany (Potsdam University, GFZ, Geomar, AWI). 32 OBSs were rented from the DEPAS international pool of instruments maintained by the Alfred Wegener Institute (Bremerhaven), Germany, while other institutions borrowed additional instruments (7 from DIAS, 4 from IDL, 3 from ROA, 4 from GEOMAR). Most of the instruments have three-component wideband seismic sensors, but three different designs of OBS frames were used. Waveform data is available from the GEOFON data centre, under network code 8J, embargoed data may be accessible upon request. We want to acknowledge the exceptional support of the whole team of able seaman, steward, cooks, engineers, mechanicians, electricians and motorman assistants of the vessel RRV Mário Ruivo. With special Thanks to José Ângelo Gomes (Captain), Luís Ramos (Superintendent), Mafalda Carapuço Vessel’s manager (IPMA), Henrique Ferreira Land logistics (IPMA), Celine Ahmed and Jen Amery (Administrative support at UCL)

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