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Dataset of wehrlitization process: insights from X-ray Micro-CT of Mt. Vulture (southern Italy) mantle xenoliths

The study of textural and chemical characteristics of mafic minerals from mantle xenoliths is essential to investigate the nature of the upper mantle in a continental geodynamic context, melts generation and their effects related to mantle metasomatism. Particular textures in mantle minerals, inclusions or secondary veins of different nature (silicates vs carbonates), bubbles, represent petrographic tools to investigate these processes within the mantle. Petrographic 2D thin sections might overlook these mineralogical features, and 3D textural analysis through X-ray computed microtomography (micro-CT) are crucial to overcome these limitations. We focused on the Mt. Vulture volcano (southern Italy) rare mantle xenoliths, brought to the surface by a melilitite-carbonatite magma (141 ka), with particular emphasis to spinel-wehrlite xenoliths and wehrlitization processes that is located close to an area of intense CO2 degassing associated to catastrophic earthquakes. Preliminary results showed interesting 3D textural distributions within the studied xenoliths-forming mantle minerals. In particular, the micro-CT allowed to furnish new constrains on the relationship between fluids entrapment and migration, and structural discontinuities. Indeed, some minerals (especially those from the wehrlite xenoliths) showed a well-correlated distribution of fluid inclusions along the secondary fracturing planes. This publication results from work conducted under the transnational access/national open access action at Istituto Nazionale di Geofisica e Vulcanologia – Osservatorio Vesuviano (INGV-OV) and supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005. The author thanks also Gianmarco Buono and Lucia Pappalardo for their support during the analyses and the post processing process.

Carbon isotopes in OIB Mantle source

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Detrital age spectra and petrological analysis of gravel-size clasts of the Oligocene-early Miocene glaciomarine sediments of the DSDP drilling Site 270, Central Ross Sea, Antarctica

This data-set contains provenance detrital data from the glacimarine sequence of Deep Sea Drilling Project Site 270. The 270 site was cored on a flank of the Central High in the central Ross Sea and recovered a thick Oligocene to lower Miocene glacimarine sequence, overlain by ~20 m of Pliocene to Recent strata. This site provides important temporal constraints on regional stratigraphy and insights into late Oligocene to early Miocene ice sheet dynamics. We analyzed eight detrital samples of glaciomarine sediments distributed along the core and two from the basement rocks recovered during coring, by using an integrated single-grain provenance approach. This multi-proxy provenance study employs conventional U-Pb detrital zircon dating integrated with apatite U-Pb and fission-track dating and trace element analysis of detrital apatite and clast petrology. The data-set suggests a general evolution from local erosion due to small ice caps to far-travelled glacial detritus responding to the continuous sea floor subsidence. The detrital age spectra of a late Oligocene diamicitite is consistent with far travelled grains from southern West Antarctica (WA), suggesting an expansion of the WA ice sheet that should be the oldest and first evidence of ice sheet growth on the WA.

A database of centrifuge analogue models testing the influence of inherited brittle fabrics on continental rifting

This dataset presents the raw data of an experimental series of analogue models performed to investigate the influence of inherited brittle fabrics on narrow continental rifting. This model series was performed to test the influence of brittle pre-existing fabrics on the rifting deformation by cutting the brittle layer at different orientations with respect to the extension direction. An overview of the experimental series is shown in Table 1. In this dataset we provide four different types of data, that can serve as supporting material and for further analysis: 1) The top-view photos, taken at different steps 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 performed analogue models, allowing for quantitative analysis of the fault pattern. 3) Short movies built from top-view photos which help to visualize the evolution of model deformation; 4) line-drawing of fault and fracture patters to be used for fault statistical quantification. Further details on the modelling strategy and setup can be found in Corti (2012), Maestrelli et al. (2020), Molnar et al. (2020), Philippon et al. (2015), Zwaan et al. (2021) and in the publication associated with this dataset. Materials used for these analogue models were described in Montanari et al. (2017) Del Ventisette et al. (2019) and Zwaan et al. (2020).

Laser ablation inductively coupled mass spectrometry trace element chemistry of sulfides from the Aouli Ag-Pb-Zn-(Cu) vein system (Upper Moulouya district, Morocco)

This data report presents the in-situ LA-ICP-MS trace element composition of sphalerite, pyrite, and chalcopyrite from the Aouli Ag-Pb-Zn-(Cu) vein system in the Upper Moulouya district, Morocco. The dataset contributes to a study focused on characterizing the element concentrations in sulfides and elucidating the ore-forming processes at the Aouli deposit. Located within the Hercynian inlier of the Upper Moulouya, this deposit hosts one of Morocco’s largest argentiferous Pb-Zn ± F ± Ba vein-type deposits. The mineralization occurs within polyphase hydrothermal veins, oriented NE-SW to E-W and WNW-ESE. These veins occur as lodes, ore shoots, or discontinuous vein infill, with their emplacement largely controlled by structural intersections. The deposit hosts a complex mineralogical assemblage, including Ni-Co-Fe arsenides and sulfarsenides, Pb-Zn-Cu sulfides, and Ag-Sb-As sulfosalts occurring in the same vein structures, which are described for the first time. Consequently, the characterization of pyrite, chalcopyrite, and particularly sphalerite will help constrain the ore-forming process and determine the physicochemical conditions (T–fS2) of the mineralizing fluids.

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).

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).

Crystal Size Distribution Analyses of Isothermal Deformation Experiments

In this work we aimed to investigate and quantify the relative importance of dynamic conditions (e.g., stirring in a Concentric Cylinder apparatus) on the crystallization kinetics of basaltic magmas (Stromboli). This was achieved by observing the final textures of the samples, analysing the resulting SEM images, and finally relating the resulting parameters to specific growth and nucleation rates. The dataset is made of: 1) A folder called "SEM Images" with two sub-folders inside, representative of the two experiments carried out, called "CG1" and "CG2.3" 2) An Excel file, consisting in 4 data sheets, where all results of image analysis are included, divided in sections. The sheets are also available in CSV format. This publication results from work conducted under the transnational access/national open access action at High Pressure - High Temperature Laboratory (HPHT Lab), Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005.

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).

Mineralogical, geochemical, microbiological and thermodynamic data from a deep hydrothermally altered profile of a semi-arid environment (Chilean Coastal Cordillera)

This data publication is supplementary to a study on microbial weathering of Fe-bearing minerals in the deep biosphere of a semi-arid environment (Chile). The dataset contains mineralogical, geochemical, microbiological and thermodynamic data of an 87 m deep drill core profile located in the Chilean Coastal Cordillera (Santa Gracia (SG)). The drilling campaign was conducted in March-April 2019 as part of the German Science Foundation (DFG) priority research program SPP 1803 “EarthShape: Earth Surface Shaping by Biota”. The project focused on how microorganisms contribute to mineral weathering and thus shape Earth´s surface. Aim of the drilling campaign was to recover the continuous weathering profile from surface to weathering front and to pinpoint as well as disentangle weathering processes at depth. For this purpose, extractable Fe pools, water-extractable organic carbon and nitrate, energy yields of Fe redox reactions, in situ microbial Fe(III) reduction, microbial Fe(III) reduction extent in microcosms, as well as community compositions of in situ and microcosms derived 16S rRNA gene amplicon sequence variants (ASVs) were determined.

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