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C’è una caratteristica centrale che distingue ChatGPT e simili da un interlocutore umano: pur sapendo rispondere in modo coerente e creativo a richieste anche complesse, sono del tutto incapaci di proporre contenuti conversazionali non puramente reattivi, manca, all’AI, la parte “affiliativa” della conversazione

This paper proposes a (re)reading of the famous section in the Tractatus Logico-philosophicus, 2.1: “We picture facts to ourselves” and its relation to the similar section in the Prototractatus, 2.1: “Facts are grasped by us in images”. We reject the dominant solution that interprets the relation between facts and images as an isomorphic relation and propose that instead it is an internal relation: there are no facts that are not perceived through images. In other words: For us, linguistic animals, there is no world independent of language.

Starting with a suggestion, the similarity between Wittgenstein and Montaigne, this article reconstructs a quick history of the substantial misunderstanding that, despite his enormous success, characterized the "Tractatus logico-philosophicus" and the role of ethical issue in this book.

Il dibattito pubblico sul coronavirus è stato caratterizzato dall’uso pervasivo della metafora della guerra. Fin dall’inizio la concettualizzazione della pandemia nei termini di guerra è stata tematizzata da giornalisti e linguisti che nehanno messo in luce i limiti. In questo articolo tematizzerò questo dibattito,discutendo l’appropriatezza della metafora bellica per concettualizzare lapandemia. Sosterrò, rifacendomi a Dedre Gentner che si tratta di una metafora che funziona finché restainconsapevole e, pertanto, la massiccia operazione di tematizzazione, porta inevitabilmente ad una perdita dei suoi egfetti perlocutivi.

una riflessione a caldo sul epidemia, infodemia, confinamento sociale. in dialogo con il dipinto di van Hoogstraten le pantofole

In this paper we will show the need for a multimodal approach to the study of metaphorical utterances. We will discuss this hypothesis showing potentials and limits of the metaphor studies conducted within Relevance Theory, which has represented the most authoritative and radical theoretical framework based on the propositional character of metaphorical utterances. In particular, we will focus on the last papers by Carston (2010, 2018), in which it is recognized that the comprehension of complex and poetic metaphors could involve the activation of mental images. We will discuss the problem that the notion of mental imagery poses to Relevance Theory and we will try to overcome these problems by an hybridization between Relevance Theory and Perceptual Symbol Theory. Then, we will suggest that local and novel metaphors, such as “love is fresh fruit”, could require the activation of mental imagery too and we will characterize this kind of metaphor in terms of compresence of narrowing, broadening and conscious experience of a multimodal mental image.

È possibile applicare i modelli offerti dalla pragmatica del linguaggio, con particolare riferimento ai lavori di Sperber & Wilson, Robyn Carston e Kasia Jaszczolt, alla comprensione delle immagini della pittura figurativa. Il tema, dibattuto soprattutto nell’ambito dei metaphor studies, ha avuto un recente sviluppo: per esempio Forceville e Clark2 (2014) hanno provato ad utilizzare il frame teorico della Relevance theory per descrivere i meccanismi linguistico-cognitivi che utilizziamo nella comprensione di un’immagine. A nostro parere questi tentativi difettano del dialogo con gli strumenti, elaborati nell’ambito della storia dell’arte e dei Visual Studies e e tendono a consegnarci un’idea ingenua di cosa significhi comprendere un’immagine. Proveremo a mettere in dialogo relegante theory con la distinzione iconologia/iconografico.

In questo articolo analizzeremo lo statuto semiotico-cognitivo dei descrittori dei vini comunemente utilizzati per asserire che un determinato vino ha sentore di frutta. Infatti, una delle caratteristiche più evidenti del lessico usato oggi per parlare del vino è la sua parentela con il lessico della frutta. Mostreremo come questa parentela tra lessico enologico e lessico della frutta si basi su un processo di dipendenza e non sia un generico fenomeno di prestito linguistico. Si tratta, infatti di un processo parassitario che trasforma il lessico della frutta da lessico asistematico con funzione denotativa – per cui con il termine “ananas” intendiamo riferirci agli ananas nel mondo – in un sistema di tipo saussuriano in grado di dar forma all’esperienza gustativa e catturare con un’adeguata granularità le differenze tra i sentori dei vini. Sosterremo che tale trasformazione sia resa possibile da processi di modulazione pragmaticolessicale che indagheremo tramite gli strumenti teorici della Relevance Theory (Sperber &Wilson 1995). Infine, mostreremo come i discorsi sul vino costituiscano e strutturino l’esperienza gustativa stessa, consentendoci di comprendere, descrivere e identificare diverse tipologie di vino.

Literal Meaning is a widely used notion, which seems to be well rooted in the strong intuition that words have a meaning in themselves. However, as pointed out in previous literature (e.g. RECANATI 2004), this theoretical notion seems to be problematic in accounting for some aspects of the nature of linguistic meaning. Embracing these criticisms, we will show how the heuristic power of this notion becomes apparent when looking at some specific types of contexts, namely those language games where it is necessary to retrieve the meaning of words in isolation. This will allow us to argue in favour of consistency of this notion with theoretical framework with a strong focus on the contextual nature of linguistic meaning. In order to do so: 1. 2. 3. We will clarify what we mean by standard notion of literal meaning and the main criticisms coming from contextualist approaches; We will show how, in spite of its weaknesses, this notion tends to be widely used, since it seems to capture the intuition that words have a meaning in themselves and therefore that languages rely on a stable lexicon which can be accessed metalinguistically; We will show how this notion can still be used within contextualist frameworks to account for some specific types of language games where those metalinguistic operations are necessary.

The meaning of an utterance is a logical issue which has to be considered as such regardless of the biocognitive constraints operating in our bodies. This (traditional) thesis assumes a definite notion of rationality that doen’t seem to withstand what we know about the limits of our rationality (Kahneman, Tversky 1979) and what emerges from the empirical evidences of cognitive sciences. These evidences pro- vide a more plausible image of linguistic comprehension, beyond there use in the context of Relevance Theory and in the psycholinguistic perspectives of the Good Enough Approach. Starting from this framework an approach to linguistic compre- hension is outlined where the performative aspect of understanding and the con- straints by which it is bound (Christiansen, Chater 2016) are fundamental elements.

In questo intervento descriverò alcune caratteristiche della relazione tra spettatore ed esperienza artistiica dal punto di vista dei meccanismi della comprensione dell’opera d’arte, con una specifico riferimento alle arti performative. Svilupperò questo contributo attraverso un confronto tra la comprensione di un enunciato e la comprensione di un’opera d’arte, utilizzando come modello le nozioni di regole e gioco linguistico elaborate da Wittgenstein. Secondo questo modello, la comprensione è parafrasabile come riconoscimento di un pattern che regola le interazioni in gioco. Mostrerò come in alcuni domini artistici la comprensione poggi sul riconoscimento di un insieme di regole che consentonio allo spettatore di ricondurre gli eventi dell’opera d’arte a quelli di situazioni piu familiari. Chiarirò questa ipotesi attraverso esempi tratti da arti performative (Erdem Gunduz, the stianding man), teatro (samuel Beckett) cinema (Michelangelo Antonioni) mostrando come la tensioen continua tra riconscimento e dissonanza realizzata attraverso una controllata violazioen delle regole crei le condizioni per l’esperienza di senso peculiare appunto all’opera d’arte.

Gli uomini da sempre sono coinvolti in pratiche narrative. L'articolo discute questa attitudine al raccontare storie mettendola in relazione al bisogno cognitivo da cui nasce. E proponendo di collegarla alla necessita cognitiva di costruire un racconto coerente della nostra storia: la nostra autobiografia.

Linguists and philosophers commonly distinguish between semantics and pragmatics, where the former concerns the truth or falsity of linguistic items and the latter concerns aspects of the use of such items that may make them unassertable even when true. Common though the distinction is, there is an ongoing controversy about where exactly the line between semantics and pragmatics is to drawn. We report two experiments meant to investigate empirically whether there is any pre-theoretic distinction that might help settle the debate. The same experiments are meant to shed light on a related question, namely, whether pragmatic aspects of language use pertain only at the level of assertability and not at that of believability. Our results suggest that ordinary people do not reliably distinguish among truth, assertability, or believability. We argue that this has consequences for the methodology of experimental semantics and pragmatics.

In this study we applied a multidisciplinary approach, coupling geophysical and geochemical measurements, to unveil the provenance of 170 obsidian flakes, collected on the volcanic island of Ustica (Sicily). On this island there are some prehistoric settlements dated from the Neolithic to the Middle Bronze Age. Despite not having geological outcrops of obsidian rocks, the countryside of Ustica is rich in fragments of this volcanic glass, imported from other source areas. The study of obsidian findings was carried out first through visual observations and density measurements. At least two different obsidian families have been distinguished, probably imported from Lipari and Pantelleria islands. Analysing the magnetic properties of the samples, these two main sources were confirmed, but the possibility of other provenances was inferred. Finally, we characterized the geochemical signature of the Ustica obsidians by performing microchemical analyses through electron microprobe (EMPA) and laser ablation (LA-ICP-MS). The results were compared with literature data, confirming the presence of the Lipari and Pantelleria sources (Sicily) and indicating for the first time in this part of Italy a third provenance from Palmarola island (Latium). Our results shed new light on the commercial exchanges in the peri-Tyrrhenian area during the prehistoric age.

A new period of eruptive activity started at Turrialba volcano, Costa Rica, in 2010 after almost 150 years of quiescence. This activity has been characterized by sporadic explosions whose frequency clearly increased since October 2014. This study aimed to identify the mechanisms that triggered the resumption of this eruptive activity and characterize the evolution of the phenomena over the past 2 years. We integrate 3He/4He data available on fumarole gases collected in the summit area of Turrialba between 1999 and 2011 with new measurements made on samples collected between September 2014 and February 2016. The results of a petrological investigation of the products that erupted between October 2014 and May 2015 are also presented. We infer that the resumption of eruptive activity in 2010 was triggered by a replenishment of the plumbing system of Turrialba by a new batch of magma. This is supported by the increase in 3He/4He values observed since 2005 at the crater fumaroles and by comparable high values in September 2014, just before the onset of the new eruptive phase. The presence of a number of fresh and juvenile glassy shards in the erupted products increased between October 2014 and May 2015, suggesting the involvement of new magma with a composition similar to that erupted in 1864–1866. We conclude that the increase in 3He/4He at the summit fumaroles since October 2015 represents strong evidence of a new phase of magma replenishment, which implies that the level of activity remains high at the volcano.

L'articolo discute la teoria dell'immagine del tractatus logico-philosophicus di Wittgenstein, a partire dall'immagine dello specchio adottando un punto di vista interpretativa debolmente "resolute".

La Fossa quiescent volcano and its surrounding area on the Island of Vulcano (Italy) are characterized by intensive, persistent degassing through both fumaroles and diffuse soil emissions. Periodic degassing crises occur, with marked increase in temperature and steam and gas output (mostly CO2) from crater fumaroles and in CO2 soil diffuse emission from the crater area as well as from the volcano flanks and base. The gas hazard of the most inhabited part of the island, Vulcano Porto, was investigated by simulating the CO2 dispersion in the atmosphere under different wind conditions. The DISGAS (DISpersion of GAS) code, an Eulerian model based on advection-diffusion equations, was used together with the mass-consistent Diagnostic Wind Model. Numerical simulations were validated by measurements of air CO2 concentration inside the village and along the crater's rim by means of a Soil CO2 Automatic Station and a Tunable Diode Laser device. The results show that in the village of Vulcano Porto, the CO 2 air concentration is mostly due to local soil degassing, while the contribution from the crater gas emission is negligible at the breathing height for humans and always remains well below the lowest indoor CO2 concentration threshold recommended by the health authorities (1000 ppm). Outdoor excess CO2 maxima up to 200 ppm above local background CO2 air concentration are estimated in the center of the village and up to 100 ppm in other zones. However, in some ground excavations or in basements the health code threshold can be exceeded. In the crater area, because of the combined effect of fumaroles and diffuse soil emissions, CO2 air concentrations can reach 5000-7000 ppm in low-wind conditions and pose a health hazard for visitors. Key Points Volcanogenic carbon dioxide plume dispersion is simulated by a numerical code Air CO2 concentration remains below the recommended threshold in inhabited area In the crater area CO2 air concentration may create breathing difficulties © 2014. American Geophysical Union. All Rights Reserved.

In 2011-2012, Santorini was characterized by seismic-geodetic-geochemical unrest, which was unprecedented since the most-recent eruption occurred in 1950 and led to fear an eruption was imminent. This unrest offered a chance for investigating the processes leading to volcanic reactivation and the compositional characteristics of involved magma. We have thus analyzed the He-Ne-Ar-isotope composition of fluid inclusions in olivines and clinopyroxenes from cumulate mafic enclaves hosted in cogenetic dacitic lavas of the 1570-1573 and 1925-1928 eruptions of Nea Kameni. These unique data on Aegean volcanism were compared with those of gases collected in quiescent periods and during the unrest. The 3He/4He ratios (3.1-4.0 Ra) are significantly lower than the typical arc-volcano values (R/Ra ∼ 7-8), suggesting the occurrence of magma contamination in Santorini plumbing system, which would further modify the 3He/4He ratio of parental magmas generated in the local metasomatized mantle. The 3He/4He values of enclaves (3.1-3.6 Ra) are comparable to those measured in gases during quiescent periods, confirming that enclaves reflect the He-isotope signature of magma residing at shallow depths and feeding passive degassing. A significant increase in soil CO2 flux from Nea Kameni and anomalous compositional variations in the fumaroles were identified during the unrest, accordingly with previous studies. Simultaneously, 3He/4He ratios up to 4.0 Ra were also measured, demonstrating that the unrest was due to the intrusion into the shallow plumbing system of a more-primitive 3He-rich magma, which is even volatile richer and less contaminated than mafic magma erupted as enclaves. This new intrusion did not however trigger an eruption.

Torre Alfina is a medium enthalphy (T=140 °C) geothermal field in Central Italy discovered and extensively explored in the years ’70 and ’80. A detailed CO2 soil flux investigation (1336 measurements over a surface of 12.6 km2) and periodic monitoring of CO2 soil release from target areas, indicate that in most of the area, even above a pressurized gas cap existing at the reservoir top, the CO2 soil flux is low and mostly within the background (48 g/m2*day) and is likely generated by biological soil respiration. Anomalous values (up to 30.250 g/m2*day) are found only in the proximity of a gas manifestation whose composition is identical to that of the gas produced by the geothermal wells. This is the only zone where a fault connecting the deep geothermal reservoir with the surface does exist. These data are compared with those of the near Latera high enthalpy geothermal field (T = 210 °C), where anomalous CO2 soil flux is recorded above the productive reservoir. The difference of CO2 soil release in the two fields is attributed to differences in the impervious cover (flysch deposits) above the carbonate reservoir, which is thin and locally lacking at Latera, and continuous and thick (>400 m) at Torre Alfina. Results demonstrate that CO2 soil flux investigations are useful in geothermal exploration, but only high flux values likely correspond to buried active geothermal reservoirs, whereas low flux values can indicate either the lack of inactive geothermal reservoir at depht or the presence of a very effective impervious cover above the reservoir.

L'articolo sostiene che il sogno di una "linguaggio perfett", inteso come un mezzo di espressione universale e semanticamente trasparente sia strettamente connesso al mito della razionalità istantanea. Il linguaggio logicamente perfetto sarebbe infatti un linguaggio nel quale tutte le relazioni logiche divengono immediatamente visibili, e la questa linguaggio, possa pensare per noi (frege, 1884). nella prima parte dell'articolo si ricostruisce la storia di questo tipo di linguaggio perfetto da Leibniz e Wittgenstein. nella seconda parte si mostra come tale linguaggio non possa esistere sulla base di recenti risultati in logica e computer science. We argue that the dream of a ‘perfect language’ – namely, a universal, unambiguous and semantically transparent medium of expression –, is deeply intertwined with the myth of instant rationality: the idea that a perfect language is one in which all logical relations becomeimmediatly visible, so that the language itself “does the thinkingfor us” (Frege 1884). In the first part of this paper we trace this versionof the dream in the works of Leibniz, Frege, Russell and Wittgenstein. In the second part we re-examine it in the light of more recent negative results in logic and theoretical computer science.

Il pianeta Terra rilascia continuamente calore verso la superficie. Questo flusso di calore è particolarmente elevato nelle zone vulcaniche (dorsali oceaniche, cordigliere, archi di isole, punti caldi) dove il magma fuso, con una temperatura di 800-1100°C, può accumularsi in serbatoi a piccola profondità (150°C), media (T=90-150°C) e bassa (T

The Colli Albani volcanic area is affected by huge degassing of likely magmatic or mantle origin, as suggested by the gas He isotopic composition. Gas rising from a buried calcareous aquifer generates several surface emissions and accumulates also in permeable layers at various depths, from 10 to 350 m, beneath impervious formations. When reached by wells, these pressurized gas pockets cause hazardous blowouts of CO 2 and H 2S, often in inhabited zone. Remedy requires the restoration of the drilled cap by cement injections, whose effectiveness can be conveniently assessed by monitoring both CO 2 soil diffuse flux and CO 2 and H 2S air concentration

Although controversy exists about the age of its most recent eruption (either 36 ka or ,23 ka), Colli Albani volcano is unanimously considered to be quiescent and not exinct. During the Holocene, several lahars were generated by overflows from Albano crater lake up to the fourth century BCE, when the Romans excavated a drainage tunnel to keep the lake level below the crater rim. Such recent activity, together with the frequent occurrence of seismic swarms underneath the crater zone, the ongoing uplift of the volcanic edifice and the magmatic affinity of the emitted gas, indicate the presence of an active magma chamber. The most likely site for a new eruption is the deep crater hosted in the southern part of the Lake Albano, where the last eruptive events occurred. Any eruption would have a strong explosive character enhanced by the interaction of magma with the water of the lake and would endanger a densely inhabited area up to the outskirts of Rome. The hazard of a new overflow from Lake Albano is very low because of the present low level of the lake. There is instead a potential for CO2 release from the deep lake water following the occurrence of rollovers, which would threaten the lake shore, a site where thousands of people spend their vacations in the summer. However, the content of dissolved CO2 is presently far from saturation and no Nyos-type events will occur today. Presently, the main hazard is related to strong gas emissions (CO2, H2S and Rn) from fractured zones and gas blowouts from wells reaching shallow gas-pressurized aquifers.

Although controversy exists about the age of its most recent eruption (either 36 ka or ,23 ka), Colli Albani volcano is unanimously considered to be quiescent and not exinct. During the Holocene, several lahars were generated by overflows from Albano crater lake up to the fourth century BCE, when the Romans excavated a drainage tunnel to keep the lake level below the crater rim. Such recent activity, together with the frequent occurrence of seismic swarms underneath the crater zone, the ongoing uplift of the volcanic edifice and the magmatic affinity of the emitted gas, indicate the presence of an active magma chamber. The most likely site for a new eruption is the deep crater hosted in the southern part of the Lake Albano, where the last eruptive events occurred. Any eruption would have a strong explosive character enhanced by the interaction of magma with the water of the lake and would endanger a densely inhabited area up to the outskirts of Rome. The hazard of a new overflow from Lake Albano is very low because of the present low level of the lake. There is instead a potential for CO2 release from the deep lake water following the occurrence of rollovers, which would threaten the lake shore, a site where thousands of people spend their vacations in the summer. However, the content of dissolved CO2 is presently far from saturation and no Nyos-type events will occur today. Presently, the main hazard is related to strong gas emissions (CO2, H2S and Rn) from fractured zones and gas blowouts from wells reaching shallow gas-pressurized aquifers.

Il dominio vulcanico laziale a nord del Fiume Tevere ospita una estesa falda di interesse regionale sostenuta da una potente sequenza di depositi appartenenti alle unità alloctone di facies toscana e tolfetana. Le discontinuità tettoniche connesse con il complesso assetto strutturale dell’area peritirrenica consente la risalita di fluidi endogeni di natura termominerale provenienti dagli acquiferi geotermici ospitati dalle sequenze carbonatiche confinate dalle unità alloctone stesse. Nella fase di risalita i gas endogeni interagiscono con le falde in relazione agli equilibri di fase imposti dalle condizioni di temperatura e pressione. Ciò fa sì che in superficie, in corrispondenza delle principali discontinuità tettoniche, si abbiano manifestazioni gassose più o meno consistenti, associate o meno a sorgenti d’acqua mineralizzata. Questa nota riporta i risultati di una ricerca interdisciplinare mirata a definire come le caratteristiche geometriche della falda delle vulcaniti, l’assetto strutturale e la consistenza dei convogli gassosi possano influenzare le caratteristiche chimico fisiche delle falde e quindi delle sorgenti. La ricerca è stata condotta a scala regionale relativamente ai distretti vulcanici vulsini e cimini e a scala di dettaglio relativamente alle più note aree di manifestazione di acque termali e/o di effusione di gas CO2. Essa si basa su consistenti campagne di rilevamento idrogeologico e chimico-fisico. A queste rilevazioni si è aggiunta quella della determinazione quantitativa delle emissioni gassose in termini di tonnellate-giorno per unità di superficie. Per meglio definire lo schema idrogeologico e geotermico dell’area di studio, sono stati prodotti dagli autori numerosi profili idrogeologici. Numerose carte tematiche, relative alla distribuzione dei valori di conducibilità, pH, temperatura delle acque sotterranee ed entità dell’emissione di CO2 consentono di valutare l’influenza del drenaggio sotterraneo della falda basale sullo specifico parametro. The Latium volcanic domain northern to the Tiber River hosts a wide aquifer of regional interest supported by a powerful sequence of deposits belonging to units of allochthonous facies “toscana” and “tolfetana”. The tectonic discontinuities associated with the complex structural setting of the perithyrrenic area allows the ascent of endogenous thermomineral fluids from the geothermal aquifer hosted by carbonate sequences which are confined by allochthonous units themselves. In the phase of ascent the endogenous gases interact with the groundwater in relation to the equilibrium phase imposed by conditions of temperature and pressure. This causes the surface, in correspondence of the main tectonic discontinuities, you have gaseous manifestations more or less consistent, associated or not to mineralized springs. This note reports the results of an interdisciplinary research aimed at defining how the geometric characteristics of the aquifer of volcanic rocks, the structural setting and the consistency of the convoys may influence the gaseous chemical and physical characteristics of aquifers and springs. The research was conducted on a regional scale in relation to the Vulsini and Cimini Volcanic Districts and at a detailed scale relatively to the most famous areas of thermal waters and / or effusion of CO2 occurrence. It is based on a consistent field hydrogeological and physical-chemical data collecting. Moreover, a quantitative determination of the gas emissions in terms of tons-days per unit of surface area has been carried out. To better define the hydrogeological and geothermal setting of the study area, many hydrogeological cross sections have been produced. Several thematic maps showing the distribution of groundwater conductivity, pH, temperature values and CO2 emission rates allow to assess the influence of the basal aquifer drainage on each single parameter.

Il dominio vulcanico laziale a nord del Fiume Tevere ospita una estesa falda di interesse regionale sostenuta da una potente sequenza di depositi appartenenti alle unità alloctone di facies toscana e tolfetana. Le discontinuità tettoniche connesse con il complesso assetto strutturale dell’area peritirrenica consente la risalita di fluidi endogeni di natura termominerale provenienti dagli acquiferi geotermici ospitati dalle sequenze carbonatiche confinate dalle unità alloctone stesse. Nella fase di risalita i gas endogeni interagiscono con le falde in relazione agli equilibri di fase imposti dalle condizioni di temperatura e pressione. Ciò fa sì che in superficie, in corrispondenza delle principali discontinuità tettoniche, si abbiano manifestazioni gassose più o meno consistenti, associate o meno a sorgenti d’acqua mineralizzata. Questa nota riporta i risultati di una ricerca interdisciplinare mirata a definire come le caratteristiche geometriche della falda delle vulcaniti, l’assetto strutturale e la consistenza dei convogli gassosi possano influenzare le caratteristiche chimico fisiche delle falde e quindi delle sorgenti. La ricerca è stata condotta a scala regionale relativamente ai distretti vulcanici vulsini e cimini e a scala di dettaglio relativamente alle più note aree di manifestazione di acque termali e/o di effusione di gas CO2. Essa si basa su consistenti campagne di rilevamento idrogeologico e chimico-fisico. A queste rilevazioni si è aggiunta quella della determinazione quantitativa delle emissioni gassose in termini di tonnellate-giorno per unità di superficie. Per meglio definire lo schema idrogeologico e geotermico dell’area di studio, sono stati prodotti dagli autori numerosi profili idrogeologici. Numerose carte tematiche, relative alla distribuzione dei valori di conducibilità, pH, temperatura delle acque sotterranee ed entità dell’emissione di CO2 consentono di valutare l’influenza del drenaggio sotterraneo della falda basale sullo specifico parametro. The Latium volcanic domain northern to the Tiber River hosts a wide aquifer of regional interest supported by a powerful sequence of deposits belonging to units of allochthonous facies “toscana” and “tolfetana”. The tectonic discontinuities associated with the complex structural setting of the perithyrrenic area allows the ascent of endogenous thermomineral fluids from the geothermal aquifer hosted by carbonate sequences which are confined by allochthonous units themselves. In the phase of ascent the endogenous gases interact with the groundwater in relation to the equilibrium phase imposed by conditions of temperature and pressure. This causes the surface, in correspondence of the main tectonic discontinuities, you have gaseous manifestations more or less consistent, associated or not to mineralized springs. This note reports the results of an interdisciplinary research aimed at defining how the geometric characteristics of the aquifer of volcanic rocks, the structural setting and the consistency of the convoys may influence the gaseous chemical and physical characteristics of aquifers and springs. The research was conducted on a regional scale in relation to the Vulsini and Cimini Volcanic Districts and at a detailed scale relatively to the most famous areas of thermal waters and / or effusion of CO2 occurrence. It is based on a consistent field hydrogeological and physical-chemical data collecting. Moreover, a quantitative determination of the gas emissions in terms of tons-days per unit of surface area has been carried out. To better define the hydrogeological and geothermal setting of the study area, many hydrogeological cross sections have been produced. Several thematic maps showing the distribution of groundwater conductivity, pH, temperature values and CO2 emission rates allow to assess the influence of the basal aquifer drainage on each single parameter.

The Albano Lake is the deepest volcanic lake in Italy and fills the youngest maar of the quiescent Colli Albani volcano. The lake has undergone dramatic level changes and overflows about ~5800 yrs B.P. and likely in 398 b.C., when Romans excavated a tunnel drain through the maar wall. Hazardous lake rollovers and CO2 release are still possible because the Albano volcano still shows active ground deformation, gas emissions and periodic seismic swarms. On November 2005, the first very high resolution bathymetric survey of the Albano Lake was performed. Here we show results provided by a Digital Elevation Model and 2-D and 3-D images of the crater lake floor which is made by coalescent and partly overlapping craters. Submerged shorelines have been identified at various depths and indicate the occurrence of lake level changes. The current lake volume is ~447.5 x 106 m3 and its critical value for outflow is ~895.7 x 106 m3. The total quantity of dissolved CO2 has been estimated to 6846 tons by chemical analyses of samples collected on May 2006. A decrease of one order of magnitude of the CO2 dissolved in the lake water below - 120 m, observed from December 1997 to May 2006 (from 4187 to 465 tons respectively), has been attributed to lake water overturn.

Recent studies suggested that Alban Hills (Rome) is a quiescent and not an extinct volcano, as it produced Holocene eruptions and several lahars until Roman times by water overflow from the Albano crater lake. Alban Hills are presently characterized by high PCO2 in groundwaters and by several cold gas emissions usually in sites where excavations removed the superficial impervious cover. Gas consists mostly of CO2 with minor H2S and the diffuse CO2 soil flux is locally very high. Accidental gas blowouts, occurred during shallow well drillings (tens to hundreds m depth) in zones with no surface gas manifestations, indicate the presence of gas pressurized aquifers confined underneath impermeable layers, within both the volcanic rock pile and the underlying Pleistocene loose sediments. Degassing mostly occurs in correspondence of bordering faults of buried horsts cut in the Mesozoic carbonate basement, hosting the main aquifer. Carbon isotopic composition (δ13CCO2) suggests that CO2 is at least partly originated by thermal decarbonation of these limestones. 3He/4He isotopic ratio of the gas (up to 1.9 Ra) is the same or even slightly higher than that of olivine and clinopyroxene fluid inclusions of the Alban Hills volcanic products, indicating a possible magmatic source for the gas. Low R/Ra values, compared to MORB and island arc magmas, are characteristic of the potassic Roman Comagmatic Province and reflect a deep involvement of crustal material in the magma genesis. The lack of high temperature fumaroles can be explained by an efficient meteoric cold water penetration and circulation in the volcano permeable terrains.

systematic CO2soil flux surveys carried out at cava dei Selcion the Colli Albani volcano (28 seasonal surveys since the year 2000), have shown a significant variation of CO2 diffuse release, with a marked decrease, from 25 to 4 tons/day, from May 2000 to August 2004, followed by a new increase. In the same time CO2 flux halved at S. Maria delle Mole (16.8 tons/day in 2000 and 8.3 tons/day in 2006). Also the total quantity of CO2 dissolved in the deep waters of the Albano crater lake decreased by one order in the period 1997-2006. The high CO2 flux values could represent the “tail” of a strong degassing episode recorded at Colli Albani in 1995 and related to local earthquakes. The following decrease of CO2 release could reflect a permeability decrease caused by hydrothermal calcite precipitation favoured by PCO2 reduction in the deep source

Ripetuti episodi esondativi sono avvenuti dal lago craterico di Albano fino probabilmente al 398 a.C. (Funiciello et al., 2002). Sull’esempio di quanto recentemente avvenuto nei laghi africani di Nyos e Monoun (Sigurdsson et al., 1987; Barberi et al., 1989; Rice, 2000) esiste la possibilità che queste esondazioni siano state causate da eruzioni vulcaniche o da improvvise violente immissioni di gas e acque calde sul fondo del lago, oppure ancora dal rovesciamento dell’acqua del lago che avrebbe portato in superficie parti profonde ricche in CO2 con conseguente liberazione di nubi letali di gas. È pertanto importante che la geochimica delle acque dei laghi craterici venga periodicamente controllata, allo scopo in particolare di appurare se vi sono evidenze di immissione di gas profondi o comunque le condizioni perché possa avvenire un accumulo di gas nelle acque profonde.