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Warming global climate threatens the stability of the polar regions and may result in cascading broad impacts. Studies conducted on permafrost in the Arctic regions indicate that these areas may store almost twice the carbon currently present in the atmosphere. Therefore, permafrost thawing has the potential to magnify the warming effect by doubling the more direct anthropogenic impact from burning of fossil fuels, agriculture and changes in land use. Permafrost thawing may also intensify the Rn transport due to the increase of fluid saturation and permeability of the soil. A detailed study of 222Rn and 220Rn activity levels in polar soils constitutes a starting point to investigate gas migration processes as a function of the thawing permafrost. Although several studies have been carried out in the Arctic regions, there is little data available from the Southern Hemisphere. The Italian – New Zealand “SENECA” project aims to fill this gap and to provide the first evaluations of gas concentrations and emissions from permafrost and/or thawed shallow strata of the Taylor Valley, Antarctica. Taylor Valley is one of the few Antarctic regions that are not covered by ice and therefore is an ideal target for permafrost investigations. Results from our field measurements highlight very low values for 222Rn and higher values for 220Rn, suggesting a shallow source. Usually the measured 222Rn activity values are controlled by the radionuclide content in the soil, the temperature of the soil, the porosity of the soil, and the water content. We applied the Akerblom formula to calculate the radon at equilibrium with the activity concentration of the 226Ra on the collected soil samples, and the presence of 222Rn amounts higher than those naturally produced by the outcropping sediments is detected. These results demonstrate the presence of preferential gas pathways through the permafrost from a deep source. It is the first time that this type of study has been performed in Antarctica and can make a significant contribution to understanding the melting permafrost processes and its implications for the environment. This dataset also represents an important benchmark for future measurements to track the melt progress of Antarctic permafrost.

Radon is a natural radioactive gas produced by the decay of its parent nuclide in bearing rocks and soils. Inhalation of radon gas poses a serious risk for human health and the World Health Organization stated the doubtless correlation between long exposure to radon gas and lung cancer. In this context, 76 indoor radon measurements in private and public buildings were performed in the Ciampino municipality. This study was carried out within the framework of the LIFE-Respire project. Indoor radon concentration was measured by using passive nuclear track detectors (CR-39) and analysed using RADOSYS system at INGV Radionuclides laboratory. Measurements were carried out in winter and summer seasons to assess the range of seasonal fluctuations, as recognised elsewhere. Results show a substantial increase of maximum indoor values in winter (up to 1575 Bq/m3) that are two times higher than those measured in the summer period (up to 764 Bq/m3). The annual mean and median values (283 and 203 Bq/m3, respectively) are both below the EU recommended limit of 300 Bq/m3.Moreover, a questionnaire on radon risk perception was designed for the specific context of the LIFE-Respire project and distributed in a sample of residents and students in the Municipality of Ciampino to measure, among many other aspects, the salience of the hazard, knowledge of the hazard and of hazard mitigation strategies, perceived preparedness of and trust in officials, sources of received information and preferred methods of receiving information, and the level of interest in the project approach (including remediation measures).

Contemporary studies conducted in northern polar regions reveal that permafrost stability plays an important role in the modern carbon cycle as it potentially stores considerable quantities of greenhouse gases. Rapid and recent warming of the Arctic permafrost is resulting in significant greenhouse gas emission, both from physical and microbiological processes. The potential impact of greenhouse gas release from Antarctica is now also being investigated. In Antarctica, the McMurdo Dry Valleys comprise 10% of the ice-free soil surface areas in Antarctica and like the northern polar regions are also warming albeit from lower mean temperatures. The work presented herein examines a comprehensive sample suite of soil gases (e.g., CO2, CH4 and He) concentrations and CO2 flux measurements conducted in the Taylor Valley during the Austral summer 2019/2020. Analytical results reveal the presence of significant concentrations of CH4, CO2 and He (up to 18,447 ppmv, 34,400 ppmv and 6.49 ppmv, respectively) at the base of the active layer. When compared with the few previously obtained measurements, we observe increasing CO2 flux rates (estimated CO2 emission in the study area of 21.6 km2 ≈ 15 tons day-1). The distribution of the gas anomaly, when compared with geophysical investigations, implies an origin from deep brines migrating from inland (potentially from beneath the Antarctic Ice Sheet) towards the coast beneath the permafrost layer. These newly obtained data provide a baseline for future investigations aimed at monitoring the changing rate of greenhouse gas emission from Antarctic permafrost, and the potential origin of gases, as the southern polar region warms.

Azerbaijan hosts the largest concentration of mud volcanoes (MVs) on Earth. Here, high sedimentation rates and deposition of thick organic-rich series resulted in petroleum basin formation and, in turn, created the ideal setting and conditions to generate widespread sedimentary volcanism. Some of the regions hosting these piercements have been broadly studied, while others (e.g. the Shamakhy-Gobustan region) are less explored. In this seismically more active part of the country, the tectonic control plays a stronger role for the emplacement of diapirs and fluid migration.Here we report a multidisciplinary study conducted on a set of six MVs (Kichik Maraza, Gizmeydan, Gushchu, Malikchobanly, Madrasa and Shikhzairli) located in the Gobustan-Shamakhy region and combine satellite image interpretation with field observations, gas sampling, CH4 and CO2 flux measurements. The studied MVs are generally hosted by anticline axes intersected by fault structures that facilitate the migration of fluids. The resulting surface morphologies include elongated (Kichik Maraza, Malikchobanly MVs) or pie-shaped (Gizmeydan, Gushchu, Shikhzairli MVs). One MV does not show an edifice and is positioned along a laterally extensive fault wall (Madrasa). Morphologies vary depending on the setting, the type of erupted mud breccia and/or the diameter of the conduit. Some of these MVs are characterized by scattered pools and gryphons where gas, water, mud and oil are released. These focused emissions are typically concentrated in the crater area (Little Kichik Maraza, Gizmeydan, Malikchobanly MVs). MVs that recently erupted can display limited or no visual gas release features (like pools or developed gryphons) since these were destroyed by erupted mud breccia flows (Big Kichik Maraza, Gushchu, Shikhzairli MVs). Copious amount of dense oil was observed at numerous gryphons of Madrasa MV. Gas analyses revealed that all the sampled seeps release methane-dominated gas that has a thermogenic origin. Molecular fractionation of this gas occurs during the vertical migration from the reservoirs. Evidence of secondary microbial methane and biodegradation is also observed at some of the seepage sites.The conducted flux measurements were carried out over the crater and the flanks of the MVs targeting the diffused miniseepage (the invisible degassing that typically occurs over vast areas at and around MV craters) and individual seepage sites (e.g. pools or gryphons). Significant degassing was detected at all the investigated structures, also at those that did not display obvious visual seepage. Results show that these MVs release in average similar CH4 Tg yr-1 like most of the other structures in Azerbaijan and one order of magnitude higher than many MV on Earth. CH4 emissions reach up to 64 tonnes yr-1 (Kichik Maraza MV) and CO2 up to 20 tonnes yr-1 (Gizmeydan MV).In more seismically active Shamakhy-Gobustan region the tectonic control plays a stronger role for the resulting morphologies of MVs, fluid migration pathways and composition.

Lusi is the nickname of the largest sub-aerial erupting clastic system on Earth. This sediment-hosted geothermal system relentlessly erupts since May 2006 in the East Java back-arc sedimentary basin. This spectacular system features two main active craters (~100 m in diameter each) surrounded by thousands of satellite active seeps that extend over a region of 7km2. Previous multidisciplinary studies revealed that Lusi is connected at depth with the neighboring Arjuno-Welirang volcanic complex through a system of faults (Watukosek Fault System) that extend from the volcano towards the north in the sedimentary basin. The migration of these mantle-derived fluids feeds the long-lasting activity of the eruption. Vigorous convection fuels the system and leads to geyser-like eruptive activity.To investigate the morphology and the effect that pre-existing geological structures may have on the development of the shallow plumbing system of Lusi, we deployed a pool of 25 IRIS V-Fullwavers to conduct a 3D deep electrical resistivity tomography extending over 15 km2 around the eruption site. The inverted data reveal the structure of the subsided area hosting the region where a mix of groundwater, mud breccia, hydrocarbons and boiling hydrothermal fluids are stored. We estimate that after 12 years of Lusi's inception, a collapse region of 0.6km2 developed around the active vents. Combining the flow rate data with our geoelectrical data, we estimate a total budget of 0.47km3 of mud breccia (i.e., including the erupted volume and that trapped in the collapse zone around the carter). Our investigation also points out the link between the well-developed Watukosek Fault System and the upwelling of the deep-sourced fluids that initiated, and still drive, the development of the new-born Lusi eruption. Lusi provides the unprecedented opportunity to study the development of the early phases of a piercement structure and its impact on society. Our study highlights how fully 3D geoloectrical methods may represent a key tool to investigate and possibly mitigate geohazards.

The Istituto Nazionale di Geofisica e Vulcanologia (INGV) has developed an interactive application, for educational purposes, in order to make schools aware of the dangers deriving from radon, and in general from harmful gases (gas hazards), near volcanic areas. To raise children awareness on the dangers related to an invisible enemy, often odorless “gases”, is not a simple task. Since our target are children between 11 and 13 years of age, we decided to develop a videogame with the scope of enabling them to learn the most appropriate solutions for identifying/avoiding/managing hazards. The use of a videogame for spreading information on gas hazards makes learning fun and, at the same time, feasible in a historic moment where Covid-19 does not allow for lessons to be physically partaken in a classroom. Furthermore, this type of learning known as “edutainment” is more effective, captivating and meaningful, allowing students to acquire a more concrete and longer remembered knowledge. The videogame, called GioGas, is a single player game running on both Android mobile phone and personal computers. GioGas has been developed using the Role Playing Game Maker MV graphic engine. The engine provides a map editor and several characters allowing for the creation of various biomes, also including the possibility to insert music. From the technical point of view the engine is based on javascript for the events creation and triggers management simplifying porting on mobile and desktop operating systems. The game characters are a INGV researcher, staying in a rented house during his vacation, and an elderly lady that asks for help to understand if her grandchild’s health issues are related to the recent digging of a well nearby the house. The characters move around in the virtual environment in different locations organized in several levels. Through the game, the student will learn the symptoms caused by gases, the instruments and the techniques to identify/measure them and the solutions to adopt to solve the problem. During the game, the researcher will hand out information and the student will choose which solution to apply: this will also stimulate student inclination to problem solving and overview capacities. Each solution will return a result in terms of risk mitigation and a score, from 1 to 3, based on the effectiveness of the identified solution. In the future, to add more stimulating and engaging elements for the student, a multiplayer mode will be developed, giving the students the possibility to challenge themselves.

Several soil gas surveys were performed from 2008 to 2015 in Medolla (Northern Italy) within a farming area characterized by macroseeps, absence of vegetation and anomalous temperatures of soil to investigate the soil gas migration mechanism and verify the presence of a buried fault intersecting the macroseeps. In this work, we show results of soil gas measurements of radon and thoron activities, and helium and carbon dioxide concentrations, which have been carried out in the area struck of the 2012 seismic sequence.We found that the seismic sequence sensibly influenced the soil gas distribution in the area. Indeed, soil gas anomalies are useful to recognize influences of surface features on natural gas migration. The study of the association of different gases with different origin and physical/chemical behaviour, the collection of a large number of samples during the dry season and the use of proper data analysis are fundamental in the comprehension of gas migration mechanism. The study of spatial distribution of soil gas anomalies can give information on the origin and processes involving deep and superficial gas species. In particular, the study of the spatial distribution of radon, often together with other soil gases, appears to be a suitable tool for identifying active tectonic structures in faulted areas.222Rn and 220Rn were recorded starting from 2012, early after the mainshock of 20th May. The May 2012 distribution map shows a broad sector of the area with anomalous values approximately aligned NW-SE. Radon vs thoron distribution data highlighted two different circulation mechanisms. After an initial perturbation of the system in May, a deep fluid migration is prevalent in September 2012. From 2013, the soil degassing returned to the main shallow origin. Over time, the anomalous high values of all the investigated species were always measured in correspondence of macroseeps supporting the hypothesis of a hidden fault. However, 222Rn values collected early after the mainshocks have ubiquitous distribution, likely due to perturbation of the system which enhanced the degassing of surficial layers and masked the deep contribution. The shallow and deep contributions presumably coexist for the other data, located at the intersection of the two trends. Over time 222Rn is better related to CO2 concentrations than CH4, in particular for the May 2012, 2013 and 2015 surveys (0.43 < r > 0.60) and, to a lesser degree, for Sept 2012 (r = 0.25). This relationship suggests that CO2 likely acts as a carrier for 222Rn allowing it to quickly reach the surface. Although, generally, radon concentrations increase with flow, elevated mass flux due to high flows can dilute the 222Rn activities and its values recorded at the surface. This phenomenon could justify the slightly anomalous values in correspondence of macroseeps.Geochemical surveys highlight the importance to carry out a discrete monitoring that can help to study the stress/strain changes related to seismic activity that may force crustal fluid to migrate up, thereby altering the geochemical characteristics of the fault zone at surface before and after earthquakes.

In the early 90’s, the Environmental Protection Agency of the Bolzano Province (NE Italy) performed a study on Indoor Radon in all the municipalities of the district (Minach et al., 1999). The aim of these measurements was to identify the areas characterized by high Indoor Radon (IR) values to realize an Indoor Radon map. Most of the municipalities that resulted to have average IR values above 400 Bq/m3, thus classified at high risk according to 90/143/EURATOM, are aligned along the Pustertal/Pusteria Valley. In this work, the relation between Radon activity, and the concentrations of other gases in the soil, and geological factors (e.g. lithology, tectonic structures) is investigated along two profiles across the Periadriatic Lineament in the Pustertal/Pusteria Valley. Samples of the petro-volumetrically relevant lithologies of the studied area have been collected, their chemical composition (XRF) and their radionuclides content (high resolution gamma-rays spectrometry) determined. The lithologies include granitoid rocks, orthogneisses, micaschists and phyllites, some of which are characterized by a high activity concentration of natural terrestrial radionuclides. As a consequence, their presence in the study area may potentially increase Radon emission (EC-JRC, 2019). Radon, CO2, CH4, O2, H2 and H2S have been measured in soil gas along the two profiles to investigate the effect of the Periadriatic Lineament (PL) on Radon exhalation. The profiles are located near Mühlen/Molini (P1) and Pfalzen/Falzen (P2), respectively. Preliminary results show two evident Radon peaks of 112 kBq/m3 and118 kBq/m3 along P1, and of 148 kBq/m3 and 157 kBq/m3 along P2. The background values are below 50 kBq/m3. These peaks correspond to two main cataclastic zones of the Periadriatic Fault system mostly buried under quaternary loosen sediments. Thus, cataclastic zones represent preferential paths for Radon mobility and exhalation. The comparison of the IR distribution map, the geochemical composition of the main lithologies and the results from the in-situ measures, clearly indicate that, although outcropping lithologies represent an important factor contributing to the IR values, they cannot justify such high IR values measured in the buildings alone. Instead, the structural features of the Periadriatic Fault system play a key role in enhancing radon exhalation, exposing to potential radon risk specific areas within the territories of the municipalities located in the Pustertal/Pusteria Valley.Keywords: Eastern Alps, Periadriatic Lineament, Radon, Indoor Radon, Natural RadioactivityReferences:Minach L., Verdi L., Marchesoni C., Amadori C. Radon in Sϋdtirol. Environmental Protection Agency. 1999.Cinelli G., De Cort M. & Tollefsen, T. European Commission, Joint Research Centre. European Atlas of Natural Radiation. 2019. (Eds.), Publication Office of the European Union, ISBN 978-92-76-08259-0, doi:10.2760/520053.

Current global climate changes represent a threat for the stability of the polar regions and may result in cascading broad impacts. Studies conducted on permafrost in the Arctic regions indicate that these areas may store almost twice the carbon currently present in the atmosphere. Therefore, permafrost thawing may potentially cause a significant increase of greenhouse gases concentrations in the atmosphere, exponentially rising the global warming effect. Although several studies have been carried out in the Arctic regions, there is a paucity of data available from the Southern Hemisphere. The Seneca project aims to fill this gap and to provide a first degree of evaluations of gas concentrations and emissions from permafrost and/or thawed shallow strata of the Dry Valleys in Antarctica. The Taylor and Wright Dry Valleys represent one of the few Antarctic areas that are not covered by ice and therefore represent an ideal target for permafrost investigations.Here we present the preliminary results of a multidisciplinary field expedition conducted during the Antarctic summer in the Dry Valleys, aimed to collect and analyse soil gas and water samples, to measure CO2 and CH4 flux exhalation, to investigate the petrological soil properties, and to acquire geoelectrical profiles. The obtained data are used to 1) derive a first total emission estimate for methane and carbon dioxide in this part of the Southern Polar Hemisphere, 2) locate the potential presence of geological discontinuities that can act as preferential gas pathways for fluids release, and 3) investigate the mechanisms of gas migration through the shallow sediments. These results represent a benchmark for measurements in these climate sensitive regions where little or no data are today available.

Azerbaijan hosts the highest concentration of mud volcanoes (MVs) on Earth with structures that may reach several kilometres in diameter and the height up to 600 m. Many of these structures alternate between periods of dormancy with vigorous eruptions. The frequency of the eruptive activity varies between MVs, and is typically related to the time required to build sufficient overpressure able to drive the extrusion of fluids and mud breccia at the surface.Lokbatan is possibly the most active MV on Earth exhibiting powerful eruptions occurring every 3-5 years. These phenomena manifest with spectacular gas flares that reach several tens of meters in height and the bursting of thousands of m3 of mud breccia resulting in spectacular mud flows that extend for more than 1.5 kilometres. Unlike other active MVs, Lokbatan does not show any visual evidence of diffuse degassing (e.g. active pools of gryphons) in the crater zone. Gas flux measurements completed with closed-chamber technique sensitive to ppmv, reveal extremely low values throughout the structure around the crater with average CH4=0.13 g/m2day and CO2=4.53 g/m2day. We suggest that after eruptive events, the mud breccia is able to seal the structure preventing the gas release and therefore promoting the overpressure build-up in the subsurface. This self-sealing mechanism allows a fast recharge of the MV resulting in more frequent and powerful eruptions. These spectacular phenomena are able to release in short time intervals massive amounts of gas, erupted mud breccia and energy due to the sudden overpressure release. Our field observations reveal the presence of large (up to ~50,000 m3) stratified blocks that were originally part of a large crater cone. These blocks were rafted > 1 km from the vent on top of mud breccia flows. We use a lubrication theory model to show that it is reasonable to transport blocks this large and this far provided the underlying mud flow was thick enough. The presence of large rafted blocks is not a unique phenomena observed at Lokbatan MV and is documented also at other large-scale structures.

The Island of Elba, located in the westernmost portion of the northern Cenozoic Apennine belt, is formed by metamorphic and non-metamorphic units derived from oceanic (i.e. Ligurian Domain) and continental (i.e. the Tuscan Domain) domains stacked toward NE during the Miocene.Offshore, west of the Island of Elba, magnetic and gravimetric data suggest the occurrence of N-S trending ridges that, for the very high magnetic susceptibility, have been interpreted as serpentinites, associated with other ophiolitic rocks. Moving towards south in Tuscan domain, along N-S fault, there is clear evidence of off-shore gas seepage (mainly CH4), which can be related to recent extensional activity.In this contest, a cold methane seep was discovered in the sedimentary basin off Elba Island, characterized by typical mud volcanoes conditions. Generally, mud volcanoes are the shallow expression of subsurface processes characterized by movements of large masses of sediments and fluids. A marine mud volcanoes is a window into different depth levels of the submerged geosphere where hydrogen sulfide, methane and other hydrocarbon-rich fluid seepage occurs caused by tectonic activity. Indeed, vertical migration of geogas, especially CH4 from the reservoir strata to the sea floor occurs along focused, permeable migration pathways, often created by faults and fractures.The sampled gas chemistry is typical of mud volcanoes, with methane as the prevalent gas component (>95 vol%) and minor gases that include carbon dioxide, nitrogen and trace amounts of helium. The combined stable C and H isotope composition of CH4 (δ13C and δ2H) highlights a thermogenic origin of fluids discharged from mud volcano, contrary to likely abiotic origin gas found in the Pomonte seep and linked to serpentinized ultramafic rock systems.The samples collected on this mud volcano are extremely depleted in 3He and their 3He/4He ratios are typical for a geological setting in which radiogenic crustal helium is strongly predominant. On the contrary, the Pomonte ophiolitic gas seeps show a mantle-derived 3He-rich component estimated in the range between 10 and 15%.Petrological data highlight the presence of siltites and marly mudstones characterized by different origin than those found on neighboring islets (shallow marine organogenic limestones); therefore, the possibility that the fragments of rock blocks, found in the mud volcano area, derive form erosional processes of the islet is discarded. The conical shapes highlighted by the multibeam echosounder are very similar to the typical backscatter signature of other mud volcanoes, thus confirming the possibilities of classify this site as mud volcano. Indeed, already during the scuba diving survey that allowed sampling gas and sediment, it was clearly observed and documented as a mud volcano.

The Castelluccio basin in the central Apennines (Italy) is a ~20-km2-wide intramontane Quaternary depression located in the hangingwall of the NW-trending and SW-dipping Vettore-Bove normal fault system (VBFS). This system is responsible for the 2016-2017 seismic sequence, culminated with the 30 October 2016 Mw 6.5 Norcia earthquake that caused widespread surface faulting affecting also the northern part of the Castelluccio basin. Available borehole and geophysical data are not enough to constrain the basin structure, infill architecture and their relations with the long-term activity of the VBFS. Therefore, we carried out an extensive 3D survey using the innovative Fullwaver (FW) technology, conceived to perform deep electrical resistivity tomography (DERT). We aimed at: a) mapping the geometry of the pre-Quaternary limestone basement and the basin infill thickness down to a depth of ~1 km; b) mapping the subsurface structure of known faults and their extent underneath the alluvial cover; c) mapping possible blind faults splays.The 3D survey covered a 23 km2 area and it was designed with the aim to map the region as regularly as possible, taking into account the rugged topography and logistic issues. We used a series of independent 2-channels receivers connected each to three grounded steel electrodes, 200 m spaced, to record the electrical field generated by a five kilowatt current regulated Time Domain Induced Polarization transmitter. Data were modelled with ViewLab software via a regularized inversion with smoothness constraints to cope with the expected subsurface strong resistivity changes, and to obtain a robust 3D resistivity model.The FW technology allowed us to constrain the geometry of the basin. The infill material is imaged as a wide, N-trending moderately resistive (< 300 Ωm) to conductive (< 100 Ωm) region, likely made of silty sands and gravels, deepening down to 500 m b.g.l. in the southern sector, suggesting the occurrence of two main depocenters. All over the basin, we identify paired high-resistivity (> 500-1000 Ωm) and low-resistivity (< 400 Ωm) belts related to the limestone basement and to the basin infill, respectively. They display NNE and NNW dominant trends. We interpret the sharp boundaries of NNE-trending belts as related to early extensional faults promoting the basin inception. The NNW-trending belts suggest the occurrence of faults that locally cross-cut the previous ones, and that we interpret as splays of the VBFS buried under the basin sedimentary cover. The recognition of different systems of extensional faults is coherent with results of high-resolution seismic profiling carried out recently in the basin. A high-resolution 2D transect with 15 m-spaced electrodes across the 2016 surface ruptures shows details of the active VBFS splay down to 300 m depth. Moreover, in the eastern sector of the survey area, low-resistivity round-shaped anomalies in the Mesozoic substratum hints for deep Miocene compressional structures. Therefore, our DERT imaging suggests a complex tectonics in the subsurface of the Norcia earthquake fault. In particular, the currently active NNW-trending faults seem to overprint a pre-existing structural framework, promoting fault segmentation at different spatial scales