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Horizontal-to-Vertical Spectral Ratios (HVSR) of NW Italy seismic stations elaborated during the "FOCUS-HVNEA" NOA-ILGE project

This data set consists of Horizontal-to-Vertical Spectral Ratios (HVSR) resulting from the application of the software package HVNEA (HV Noise and Earthquake Automatic Analysis) with the aim of comparing them with those resulting from the application of another method, namely STATION (Seismic sTATion and sIte amplificatiON). The results, relative to more than 24,000 HVSR, derive from the processing of 700,000 seismograms recorded over different time periods by 8 stations of the networks IV (Italian Seismic Network), GU (Regional Seismic Network of North Western Italy) and GV (Mobile RSNI). To compare the results of the two methods as accurately as possible, the waveforms were subjected to the same preprocessing already used to elaborate the results stored in the STATION database. To this end, the methodological workflow applied with HVNEA for station IV.MURB involved the selection of segments from continuous recordings for each event reported in the INGV catalogue located within a radius of 120 kilometres from the station. Starting from the automatically picked S-wave onsets, 12-second windows were then extracted and used for the analysis of earthquake recordings. Regarding the noise analysis, it should be noted that STATION again considers 12-second windows selected before the P-wave onset, while HVNEA requires the use of a signal window of at least 60 seconds. A window of 3,600 seconds was used for the analysis. The comparison of the HVSR was performed in the frequency band 0.1–15 Hz. All analysed curves, for both earthquake and noise recordings, show generally similar shapes and identify significant peaks in correspondence of the same frequency ranges, although the amplitudes obtained with STATION are systematically higher than those obtained with HVNEA. To obtain a quantitative comparison, various statistical metrics commonly used to measure the discrepancy between data sets were applied, namely the Mean Squared Error, the Mean Absolute Error and the Pearson Correlation Coefficient. This publication results from work conducted under the transnational access/national open access action at the Site effects Laboratory – INGV L’Aquila supported by WP3 ILGE–MEET project, PNRR–EU Next Generation Europe program, MUR grant number D53C22001400005.

Magnetic biomonitoring of airborne metallic particles using lichen transplants on cultural heritage – The Jerónimos Monastery, Lisbon, Portugal. Preliminary Results

Magnetic biomonitoring employing lichens transplants is a non-invasive and low-cost method to evaluate airborne particulate matter (PM) pollution originated from urban traffic. This study was designed to assess the indoor deposition of traffic-related PM within the 16th-century Jerónimos Monastery in Lisbon, employing lichen transplants exposed during two distinct periods of 11weeks each. Data includes the low field magnetic susceptibility values for all the lichen transplants, exposed during summer 2024. This publication results from work conducted under the transnational access/national open access action at Paleomagnetic Laboratory of the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in Rome supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005.

Microstructure and mechanical properties of massive and porous of lavas from S. Miguel Island (Azores, Portugal)

The role of elongated pores and crystals of lavas influences their mechanical and physical behaviour, providing a first microstructural clue. In the context of a doctoral project, two samples – a trachyte and a basalt/andesite (s.l.) - representative of Fogo Volcano (S. Miguel Island, Azores, Portugal) were collected as part of an intact rock study. They were microstructurally assessed in the INGV-OV (Naples) using the ZEISS Xradia Versa 410 X-ray computed microtomography to obtain high-resolution 3D images, as well as to perform real-time in-situ mechanical tests (uniaxial – 7 mm diameter cylinders - and Brazilian – 13 mm diameter discs) to assess how elongated pores/crystals control strength. In addition to 3D images of the samples, which allow segmentation of the pore space and crystals, mechanical tests show that trachytes are more competent than vesicular basalts/andesites. Both pores and crystals control the development of the crack pattern.

CAMSIZER Particle Size Data from Explosive Paroxysms of Mt. Etna (2011–2025)

Mt. Etna in Catania, Italy, is an active volcano that has served as a natural laboratory for many volcanologists worldwide. Its paroxysms are unique eruptive events caused by a complex magmatic system that, despite being one of the most studied volcanoes, there is still an open field to contribute to the understanding of magma dynamics and degassing. This data set is a compilation of grain-size and shape measurements of 14 tephra samples of Mt. Etna. The tephra samples correspond to some of the most explosive cycles and events of the volcano from 2011 to 2025. The measurements were obtained using CAMSIZER through the ILGE TNA grant funding at INGV sezione di Catania. This dataset is the basis for a research project investigating the controls on the volume of gases and magma emitted during an eruption of Mt. Etna. This publication results from work conducted under the transnational access/national open access action at Sedimentology Laboratory – INGV sezione di Catania supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005.

Trace element analysis of the main minerals in the Salitre lamprophyre (APIP, Brazil)

The Upper Cretaceous Salitre intrusion, subdivided into Salitre I and Salitre II and dated to ~86-82 Ma by Sonoki and Garda (1988), is part of the Alto Paranaíba Igneous Province (APIP, Fig. 1) in Brazil, which is one of the largest ultrapotassic / carbonatitic / kimberlitic provinces in the world. The intrusion is characterized by the presence of lamproites, carbonatites and one lamprophyre (analyzed here), as well as along with a variety of intrusive cumulitic rocks. Among the Salitre studied samples, this alkaline lamprophyre is characterized by low SiO2 (35.6 wt%), ultrapotassic (K2O/Na2O = 5; K2O = 4.4 wt%) and peralkaline (PI = 1.3). It exhibits variable MgO content (14 wt%) and is enriched in REEs (∑REE=~1,300 ppm) and other trace elements (Nb, Ta, Zr, Hf, Sr, Ba). This lamprophyre is characterized by olivine and phlogopite phenocrysts set in a fine-grained groundmass of clinopyroxene, apatite, phlogopite, magnetite, chromite, and perovskite, with rare titanite and garnet; kalsilite is absent. Analyzing the trace elements of the main minerals in this lamprophyre helped us learn more about the origin and evolution of these magmas, as well as their possible genetic link with the other Salitre rocks. This analysis also provided important information about their enrichment in rare earth elements (REEs) and high field strength elements (HFSEs). This publication results from work conducted under the transnational access/national open access action at Mass spectrometry la-icp laboratory (IGG-CNR, Italy) supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005.

Intercalibration of the intra-laboratory 40Ar/39Ar reference material Drachenfels sanidine

The dataset contains full 40Ar/39Ar geochronological data completed by multi-collector noble-gas mass spectrometry using the laser total fusion technique on sanidine separated from the Drachenfels trachyte (Drachenfels, Bad Godesberg, Germany). The Drachenfels sanidine represents a useful intra-laboratory reference material for laser work. The purpose of the dataset is to share updated intercalibration data for the intra-laboratory Drachenfels sanidine, relative to the widespread fluence monitors Alder Creek sanidine and Fish Canyon sanidine, that can be used in future 40Ar/39Ar geochronological studies. W. McIntosh (New Mexico Geochronology Research Laboratory, Socorro, NM), P. Renne (Berkeley Geochronology Center, Berkeley, CA) and J.R. Wijbrans (Vrije Universiteit Amsterdam, NL) kindly provided splits of FCs, ACs and DRA1, respectively. The Ar laserprobe facility was realized with the financial support of CNR. The CO2 laser system was acquired within the PNRR – Mission 4, “Education and Research” - Component 2, “From research to business” - Investment line 3.1, “Fund for the creation of an integrated system of research and innovation infrastructures” - Project IR0000025 MEET.

Results from analogue inversion experiments of extensional basins parallel and oblique to their boundaries with inferences from the European eastern Southern Alps

This image dataset contains results (original top-view and cross-section photographs) obtained from a series of 12 crustal-scale physical analogue modelling experiments performed in the Tectonic Modelling Laboratory (TecLab) at Utrecht University. We employed analogue modelling to study the inversion of extensional basins that are parallel and oblique to their boundaries. The key parameters of this study are: (i) the obliquity angle (0°, 10° or 20°) of shortening in relation to the strike of the initial rift structures; (ii) the basal décollement rheology; and (iii) the rheology of the basin fill. All analogue experiments are rectangular, 2 cm thick and consist of deformable brittle or brittle–ductile layers. Deformable parts in entirely brittle models are made of a homogeneous layer of quartz sand for the initial, non-stretched, pre-rift model crust. The subsequently resulting grabens are filled with syn- to post-extensional sediments of quartz sand, feldspar sand, or glass beads. Variations to these setups entail either a brittle layer of glass beads at the base of the above described brittle crust, or, for brittle-ductile models, a viscous layer of PDMS silicone putty with fillers. All experiments are built on one fixed above two mobile plastic sheets, their transition is pre-defining velocity discontinuities (VDs). In a first stage, deformation is induced in all models by two electric motors pulling the two mobile plastic sheets in opposite directions parallel to the backstop. These sheets are then fixed once the extensional phase is finished. VDs positioned both orthogonally and obliquely with respect to the backstop allow graben structures to form at angles of 0°, 10° and 20° to the subsequent shortening direction. In a second stage, a rigid backstop moves into the model to create compressive deformation within the entirely brittle or brittle-ductile layers. Top-view photographs were taken at regular time intervals throughout each experiment (see below for details). Cross-section photographs were taken at the end of each experiment. Therefore, the top-view photographs enable surface deformation to be tracked and analysed through time and space, while the cross-sections demonstrate the overall vertical deformation of each model. For more details about the models, see Sieberer et al. (2023). The properties of the materials used are described in Sieberer et al. (2023), Klinkmüller et al. (2016) and Willingshofer et al. (2018). All models are scaled according to the principles of geometric, rheological, and kinematic similarity between nature and models (Hubbert, 1937; Weijermars & Schmeling, 1986).

Carbon isotopes in OIB Mantle source

Other

Trace element concentration of minerals in the Morro São João malignites (Serra do Mar, Brazil)

The Morro São João intrusion is located in the easternmost part of the Serra do Mar province, along the Cabo Frio lineament (Fig. 1) and has an area of approximately 10 km². It is a Late Cretaceous intrusion formed by clinopyroxenites, melagabbros, shonkinites, malignites, nepheline syenites, and phonolite dikes, without olivine, and is thought to have formed by closed system crystallization of a fairly evolved tephritic melt of potassic/ultrapotassic affinity (cf. Brotzu et al., 2007). We have analyzed two malignites, and specifically, their liquidus phases (clinopyroxene, titanite, garnet, amphibole). Analyzing the trace elements in these minerals helps us to better understand the different fractionation of the elements in these coexisting phases, and the implications for the evolution processes that occurred in the Morro São João magma reservoir. These analyses also provided important information about the concentration of rare earth elements (REEs) and high field strength elements (HFSEs), and their change with the magmatic evolution of the suite. This publication results from work conducted under the transnational access/national open access action at Mass spectrometry la-icp laboratory (IGG-CNR, Italy) supported by WP3 ILGE - MEET project, PNRR - EU Next Generation Europe program, MUR grant number D53C22001400005.

Rheology of PDMS Korasilon G20OH (#1000039264) used at the Laboratory for Experimental Tectonics at GFZ Helmholtz Centre for Geosciences, Potsdam, Germany

This dataset provides rheometric data of the PDMS Korasilon G 20 OH used for analogue modelling at the Laboratory for Experimental Tectonics at GFZ Helmholtz Centre for Geosciences, Potsdam, Germany. The batch number is 1000039264, purchased in 2022 and opened in 2026. The material sample has been analyzed at the Laboratory for Experimental Tectonics at GFZ Helmholtz Centre for Geosciences, Potsdam (HelTec) using an Anton Paar Physica MCR 301 rheometer in a cone-plate configuration at room temperature (21˚C). Rotational (controlled shear rate) tests with shear rates varying from 10^-4 to 10^-1 s^-1 were performed. According to our rheometric analysis, the material is quasi-Newtonian (n~1) at strain rates below 10^-2 s^-1 and weakly shear rate thinning above. The viscosity of G 20 OH is 1.8*10^4 Pa s.

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