Magma Degassing as a Source of Long-Term Seismicity at Volcanoes: The Ischia Island (Italy) Case.

Transient seismicity at active volcanoes poses a significant risk in addition to eruptive activity. This risk is powered by the common belief that volcanic seismicity cannot be forecast, even on a long term. Here we investigate the nature of volcanic seismicity to try to improve our forecasting capacity. To this aim, we consider Ischia volcano (Italy), which suffered similar earthquakes along its uplifted resurgent block. We show that this seismicity marks an acceleration of decades-long subsidence of the resurgent block, driven by degassing of magma that previously produced the uplift, a process not observed at other volcanoes. Degassing will continue for hundreds to thousands of years, causing protracted seismicity and will likely be accompanied by moderate and damaging earthquakes. The possibility to constrain the future duration of seismicity at Ischia indicates that our capacity to forecast earthquakes might be enhanced when seismic activity results from long-term magmatic processes, such as degassing.

Construction of the optical part of a time-of-flight detector prototype for the AFP detector.

We present the construction of the optical part of the ToF (time-of-flight) subdetector prototype for the AFP (ATLAS Forward Proton) detector. The ToF detector in conjunction with a 3D silicon pixel tracker will tag and measure protons originating in central exclusive interactions p + p → p + X + p, where the two outgoing protons are scattered in the very forward directions. The ToF is required to reduce so-called pileup backgrounds that arise from multiple proton interactions in the same bunch crossing at high luminosity. The background can fake the signal of interest, and the extra rejection from the ToF allows the proton tagger to operate at the high luminosity required for measurement of the processes. The prototype detector uses fused silica bars emitting Cherenkov radiation as a relativistic particle passes through it. The emitted Cherenkov photons are detected by a micro-channel plate multi-anode Photomultiplier Tube (MCP-PMT) and processed by fast electronics.

Global thermal spring distribution and relationship to endogenous and exogenous factors.

Here we present digitization and analysis of the thermal springs of the world dataset compiled by Gerald Ashley Waring in 1965 into a collection of analog maps. We obtain the geographic coordinates of ~6,000 geothermal spring areas, including complementary data (e.g., temperature, total dissolved solids, flow rate), making them available in electronic format. Using temperature and flow rate, we derive the heat discharged from 1483 thermal spring areas (between ~10-5 and ~103 MW, with a median value of ~0.5 MW and ~8300 MW in total). We integrate this data set with other global data sets to study the relationship between thermalism and endogenous and exogenous factors with a supervised machine learning algorithm. This analysis confirms a dominant role of the terrestrial heat flow, topography, volcanism and extensional tectonics. This data set offers new insights and will boost future studies in geothermal energy exploration.

Statistics of seismicity to investigate the Campi Flegrei caldera unrest.

The knowledge of the dynamic of the Campi Flegrei calderic system is a primary goal to mitigate the volcanic risk in one of the most densely populated volcanic areas in the world. From 1950 to 1990 Campi Flegrei suffered three bradyseismic crises with a total uplift of 4.3 m. After 20 years of subsidence, the uplift started again in 2005 accompained by a low increment of the seismicity rate. In 2012 an increment in the seismic energy release and a variation in the gas composition of the fumaroles of Solfatara (in the central area of the caldera) were recorded. Since then, a slow and progressive increase in phenomena continued until today. We analyze the INGV - Osservatorio Vesuviano seismic catalogue of Campi Flegrei from 2000 to 2020 in order to look for any variation in the seismic parameters and compare them with geochemical monitored ones. A remarkable correlation between independent variables of earthquake cumulative number, CO/CO2 values and vertical ground deformation reveals a likely common origin. Moreover the correlation between all the variables here analysed enlightens that the same origin can cause the temporal behavior of all these variables. We interpret the seismological, geochemical and geodetic observable in terms of the injection of magmatic fluids into the hydrothermal system or its pressurization.

Analysis of 7-years Radon time series at Campi Flegrei area (Naples, Italy) using artificial neural network method.

This paper reports the analysis of soil 222Rn data recorded over 7-years in the volcanic caldera of Campi Flegrei (Naples-Italy). The relationship between Radon activity concentration and several geophysical, geochemical and meteorological parameters, influencing the gas emissions, is estimated by the Artificial Neural Network (ANN) method. The analysis goals are: the estimation (replication) of the Radon time series from influencing parameters, the forecasting of an unknown part of it, and the search for anomalies. Results prove: (i) the effectiveness of the ANN method; (ii) Radon follow the periods of agitation of the caldera, demonstrated by the comparison with previous works using different methods.

Correlation between tectonic CO2 Earth degassing and seismicity is revealed by a 10-year record in the Apennines, Italy.

Deep CO2 emissions characterize many nonvolcanic, seismically active regions worldwide, and the involvement of deep CO2 in the earthquake cycle is now generally recognized. However, no long-time records of such emissions have been published, and the temporal relations between earthquake occurrence and tectonic CO2 release remain enigmatic. Here, we report a 10-year record (2009-2018) of tectonic CO2 flux in the Apennines (Italy) during intense seismicity. The gas emission correlates with the evolution of the seismic sequences: Peaks in the deep CO2 flux are observed in periods of high seismicity and decays as the energy and number of earthquakes decrease. We propose that the evolution of seismicity is modulated by the ascent of CO2 accumulated in crustal reservoirs and originating from the melting of subducted carbonates. This large-scale, continuous process of CO2 production favors the formation of overpressurized CO2-rich reservoirs potentially able to trigger earthquakes at crustal depth.

Continuous radon monitoring during seven years of volcanic unrest at Campi Flegrei caldera (Italy).

This is a seven-year study (1/7/2011-31/12/2017) of radon monitoring at two sites of Campi Flegrei caldera (Neaples, Southern Italy) that in the last 70 years experienced repeated phases of volcanic unrest. The sites are equipped with devices for radon detection, based on the spectrometry analysis of the α-particles of radon daughters. A hybrid method, as combination of three known methods, is applied for the identification of residuals (anomalies) and trends of the time series of Radon. The results are compared with the following indicators of current caldera unrest: the tremor caused by the major fumarolic vent registered by a seismic station; the cumulative of background seismicity; the maximum vertical deformation acquired by GPS networks during the current phase of uplift; the temperature-pressure of the hydrothermal system estimated based on gas geo-indicators. The comparisons show strong correlation among independent signals and suggest that the extension of the area affected by current Campi Flegrei crisis is larger than the area of seismicity and of intense hydrothermal activity from which the radon stations are 1-4 km away. These results represent an absolute novelty in the study of a such calderic area and mark a significant step forward in the use and interpretation of the radon signal.

Monitoring diffuse volcanic degassing during volcanic unrests: the case of Campi Flegrei (Italy).

In volcanoes with active hydrothermal systems, diffuse CO2 degassing may constitute the primary mode of volcanic degassing. The monitoring of CO2 emissions can provide important clues in understanding the evolution of volcanic activity especially at calderas where the interpretation of unrest signals is often complex. Here, we report eighteen years of CO2 fluxes from the soil at Solfatara of Pozzuoli, located in the restless Campi Flegrei caldera. The entire dataset, one of the largest of diffuse CO2 degassing ever produced, is made available for the scientific community. We show that, from 2003 to 2016, the area releasing deep-sourced CO2 tripled its extent. This expansion was accompanied by an increase of the background CO2 flux, over most of the surveyed area (1.4 km2), with increased contributions from non-biogenic source. Concurrently, the amount of diffusively released CO2 increased up to values typical of persistently degassing active volcanoes (up to 3000 t d-1). These variations are consistent with the increase in the flux of magmatic fluids injected into the hydrothermal system, which cause pressure increase and, in turn, condensation within the vapor plume feeding the Solfatara emission.

Clues on the origin of post-2000 earthquakes at Campi Flegrei caldera (Italy).

The inter-arrival times of the post 2000 seismicity at Campi Flegrei caldera are statistically distributed into different populations. The low inter-arrival times population represents swarm events, while the high inter-arrival times population marks background seismicity. Here, we show that the background seismicity is increasing at the same rate of (1) the ground uplift and (2) the concentration of the fumarolic gas specie more sensitive to temperature. The seismic temporal increase is strongly correlated with the results of recent simulations, modelling injection of magmatic fluids in the Campi Flegrei hydrothermal system. These concurrent variations point to a unique process of temperature-pressure increase of the hydrothermal system controlling geophysical and geochemical signals at the caldera. Our results thus show that the occurrence of background seismicity is an excellent parameter to monitor the current unrest of the caldera.

[Preliminary considerations on the behavior of single plasmatic free fatty acids in obese subjects exposed to lipolytic stimulus before and after a period of caloric restriction]. / Considerazioni preliminari sul comportamento dei singoli acidi grassi liberi plasmatici in soggetti obesi sottoposti a stimolo lipolitico prima e dopo un periodo di restrizione calorica.

The compositions of the plasma free fatty acid picture changes in relation of the metabolic situation, which is not that theoretically predictable from the adipocyte triglycerides. After a meal, this is due to the existence of a labile storage pool, which derives its features directly from those of the food lipids. In the fasting subject, when this compartment has exhausted its remains, the failure of the NEFA picture to correspond to that of the fats constituting the stabel pool may be attributable to selective release, or to preferential utilisation of each fatty acid. Analysis of the composition performed a very short time after a supramaximal lipolytic stimulus, i.e. when the release of fatty acids surpasses their peripheral removal, by confirming the differences noted under basal conditions, suggests that the first theory used to explain the phenomenon is most likely the correct one.

Nutritional status and body composition of adolescent female gymnasts.

Nutritional status and body composition of 26 young female gymnasts (average age 12 years) were studied. The body fat percentage (15% of total body weight) is low, still consistent with an excellent health. The caloric intake is lower (1552 kcal/day) than that recommended for their age group, however it is still within the standard by body weight (43 kcal/kg). They show and insufficient assumption of carbohydrates (47.7%), mineral salts and vitamins, so that a more detailed alimentary information is required in order to avoid undesired consequences on sport performance and growth rate.

Measurement of the D(s)+ lifetime.

A high statistics measurement of the D(s)+ lifetime from the Fermilab fixed-target FOCUS photoproduction experiment is presented. We describe the analysis of the two decay modes, D(s)+ --> phi(1020)pi+ and D(s)+ -->K*(892)0K+, used for the measurement. The measured lifetime is 507.4 +/- 5.5(stat) +/- 5.1(syst) fs using 8961 +/- 105 D(s)+ --> phi(1020)pi+ and 4680 +/- 90 D(s)+ --> K*(892)0K+ decays. This is a significant improvement over the present world average.

[Relationships between programmed physical activity and risk factors in atherosclerosis]. / Osservazioni sui rapporti tra attivita' fisica programmate e fattori di rischio dell'aterosclersoi.

The lipidemic pattern has been evaluated in 40 systematically trained subjects and in 43 subjects of same age and BMI sedentary ones. The mean CT concentration of active subjects was not different from that of the sedentary group, whereas HDL-C was significantly higher and TG significantly lower, CT/HDL-C was significantly lower in active subjects. The obtained results show that systematic physical activity, even if not at agonistic level, can induce antiatherogenic modifications of the lipidemic pattern.

[Evaluation of the accuracy of precipitation methods for HDL cholesterol determination]. / Valutazione dell'accuratezza dei metodi di precipitazione per il dosaggio del colesterolo delle HDL.

Several methods for HDL-Cholesterol determination have been proposed; the over-floating cholesterol evaluation after non-HDL lipoproteins precipitation by polyanions with bivalent cations or neutral polymers is practical and not expensive, but it's accuracy and precision must be strictly control led. The Authors, after a review and a quality-check of the most used methods, conclude that the best accuracy for HDL-Cholesterol determination is provided by Dextransulphate-Mg-chloride and Phosphotungstate-Mg-chloride at pH 7,5.

[Influence of alcohol intake and smoking on plasma HDL cholesterol in active and sedentary subjects]. / Interferenza dell'assunzione di alcool e del fumo sulla concentrazione plasmatica del colesterolo HDL in soggetti attivi e sedentari.

The effect of physical activity, of smoking habit and alcohol assumption on plasma HDL-cholesterol has been evaluated in 40 normolipidaemic male active subjects and in 43 non-active ones. The comparison have been performed after covariance adjustment for potentially confounding variables. Physical activity increases and smoking habit decreases HDL-cholesterol plasma levels; no effects depending on alcohol consumption have been found.

Effects of physical activity and diet on lipemic risk factors for atherosclerosis in women.

Serum lipoproteins were studied in active and sedentary young women. The groups were matched for age, body weight, and blood pressure. A quantitative and qualitative evaluation of the diet was performed. In spite of a higher intake of saturated fat and cholesterol, serum concentrations of triglyceride, total cholesterol, and low-density lipoprotein cholesterol in the active group were not significantly different from the controls. Nevertheless, high-density lipoprotein cholesterol (HDL-C) levels were significantly higher in the active subjects even after covariance adjustment for nutrient intake; therefore, the HDL-C increase seems to depend on physical activity "per se" rather than on differences in diet.