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The Colli Albani is the quiescent volcano that dominates the southwestern skyline of Roma (Italy). The last eruption occurred during the Holocene, from the eccentric Albano maar, along its western slope. The volcano is presently affected by cyclic seismic swarms, ground uplift and diffuse CO2 degassing. The degassing has caused several deadly incidents during the last years and constitutes a major civil protection concern, as the volcano slopes are densely inhabited. Nevertheless, the volcano does not have a permanent monitoring network, and the background level and anomalous CO2 levels, the relationship between the gas release and the seismic and ground deformation activity at the Colli Albani are still to be defined. The aim of this work is to define the historical record of CO2 release. Evidences of deep CO2 periodic release during the last 2000 years in the area of Colli Albani volcano (Roma, Italy) are offered from speleothems studies. A Roman-age stone mine, now used for mushroom cultivation, is decorated with actively growing speleothems, characterised by depositional hiatuses. Different levels of four stalactites, separated by depositional unconformities, and several samples from a single depositional cycle belonging to a stalagmite have been dated by U/Th method and analysed for their O and C isotopic composition. Eight cycles of deposition have been identified from 90–110 A. D. to 1350–1370 A.D., some of which are recognised across different speleothems. The age gap dividing different growth layers is in the order of one to few hundred years giving a temporal span for periodic interruption of speleothems deposition. O and C isotopic analyses performed on the samples collected from a single cycle (the oldest) have shown that the composition of the mother solutions was initially mainly meteoric and that a progressive increase in the input of a deep component rich in CO2 (up to a proportion of 20–30%) occurred just before the interruption of the speleothem deposition. This could be due to a progressive increase of the acidity of the water solutions that caused the undersaturation of fluids. If we extrapolate this mechanism to the other cycles of deposition, being characterised by analogue isotopic compositions, we can hypothesise periods of deposition interrupted by episodes of CO2 release which in the Colli Albani volcano are often recorded in coincidence with earthquakes. Therefore we have correlated the hiatuses with some of the largest historical earthquakes interesting to the city of Rome.

Nell’ambito delle attività del “Progetto Sinkhole de! Lazio” una delle collaborazioni che maggiormente ha prodotto contributi significativi ai fini della ricerca, è stata quella tra i gruppi di lavoro di Idrogeologia e di Geochimica del Dipartimento di Scienze Geologiche dell’Università Roma TRE.In particolare lo scopo di questa collaborazione è stato lo studio dei processi idrogeologici ed idrogeochimici che caratterizzano le aree a rischio sinkhole.In questa nota vengono sintetizzati i risultati di uno studio specifico condotto nella Piana Pontina tra il 2001 e il 2003, ovvero l’analisi delle caratteristiche idrogeologiche e idrogeochimiche del Gruppo dei Laghi del Vescovo (LT).In questo settore sono presenti quattro forme di sprofondamento che, durante le fasi precedenti del Progetto, sono state riconosciute come forme di sinkhole coalescenti; di queste, due (Lago Verde e Lago Nero) sono state studiate mediante l’uso di metodologie geochimiche elementari e isotopiche.Durante le campagne di raccolta dati sono state condotte analisi in situ e campionamenti.Le analisi sul terreno hanno riguardato i parametri chimico-fisici e il contenuto di 222Rn sia nelle acque che nei fluidi interstiziali contenuti nel sedimento di fondo lago, mentre i campionamenti, eseguiti su più punti e diverse verticali in ognuno dei due laghi, sono stati finalizzati alla caratterizzazione della matrice idrogeochimica delle acque dei laghi e di alcune sorgenti di riferimento, esterne ai bacini lacustri.Il Rn-budget eseguito sui dati raccolti ha permesso di identificare i punti di immissione delle sorgenti sublacuali, la loro portata, la loro appartenenza alla circolazione carsica nonché la contaminazione ad opera di convogli fluidi risalenti dal profondo, lungo i sistemi di faglie che interessano il margine della dorsale lepina.I dati raccolti hanno peraltro fornito elementi utili a sostenere il modello concettuale di sviluppo dei sinkhole in aree di risorgenza.

We appreciate very much Hearty and Dai Pra’s Comment and their interest in the Taranto area, but we find that the comment runs into some misreading (e.g. look better at Table 2 and Fig. 5). Our paper presents the results of a multidisciplinary study of some new sections.

Grotta Savi, which opens on the flanks of Monte Stena in Rosandra Valley (Carso Triestino, Italy), consists in a network of sub-horizontal galleries developed from 300 to 350 meters a.s.l., and a total extension of >4 km. SV1 stalagmite, which comes from the inner part of the cave, is the first European speleothem that spans continuously the last 17 ka. Eighteen MC-ICPMS U/Th method datings were obtained from the 27 cm tall stalagmite, and 345 stable isotope analyses were carried out along its growth axis (mean resolution: 50±43 yrs). The stalagmite began to growth at 16.8±0.51 ka, and the axial growth rate was very low (below 10 µm/yr) until the end of the Younger Dryas From ~10.67 to ~7.59 ka a faster axial growth rate was recorded (30 to 44 µm/yr). The δ18O record reflects the amount of water that fed the stalagmite, which depends on mean annual rainfall amount and by the evapotranspiration at the surface. The δ18O record is positively correlated with the same record from Soreq Cave in Israel (BAR-MATTHEWS ET AL., 1997), and inversely with the 18O record of GISP2 ice core (GROOTES ET AL., 1993). For the more recent part of SV1, we observed a positive correlation between δ18O-calcite and the reconstructed mean annual temperature for the last 500 years in the Alps (LUTERBACHER ET AL. 2004). The strong temperature increase between 1800 AD and today is replicated by the positive δ18O trend in SV1.

Sulla parte più recente (72 cm) di una carota assiale estratta da una grossa stalagmite ancora in formazione nel sistema carsico “Grotta del Fiume - Grotta Grande del Vento” (Gola di Frasassi, Ancona) sono state effettuate datazioni col metodo MC-ICPMS U/Th, analisi isotopiche di O e C e uno studio petrografi co. La parte più antica della carota (da 104 a 72 cm dal top), caratterizzata da elevata porosità e tracce di dissoluzione, non è stata analizzata. L’analisi petrografi a ha rivelato che la stalagmite è costituita quasi interamente da calcite “colonnare allungata”. A 11 mm dalla sommità della concrezione, si osserva un marcato passaggio tessiturale da colonnare allungata (sotto) a dendritica (sopra). Le datazioni hanno permesso di stabilire che lo speleotema ha iniziato a formarsi prima del Dryas Recente, con tasso medio di accrescimento di 227 μm/anno tra 9,63±1,06 e 8,84±0,49 ka e una successiva brusca diminuzione a 51 μm/anno tra 8,60±0,34 e 5,35±0,37, cui fanno seguito tassi di crescita tra 23 e 31 μm/anno per i restanti 5350 anni. Si nota una tendenza positiva del δ18O dall’inizio alla fi ne del concrezionamento (da -8,0‰ a -7,2‰) interrotto da due singoli picchi negativi a 3,6 ka e 2,0 ka, evidenziati anche nel record del δ13C. L’andamento del δ18O potrebbe rispecchiare un graduale riscaldamento da 12 ka ad oggi, oppure essere legato ad una progressiva diminuzione della piovosità media annua, con conseguente arricchimento nell’isotopo pesante nella zona di evaporazione (Mediterraneo Orientale), analogamente a quanto evidenziato nella Grotta di Soreq (Israele). Il trend generale del profi lo del δ13C è negativo fi no a circa 2 ka (da -5,8‰ a -9,5‰), mentre gli ultimi 2000 anni sono caratterizzati da un aumento del δ13C fi no al valore attuale di -5,07‰. In particolare, si osserva un arricchimento molto rapido di quasi il 2‰ tra il 1200 e il 1350 AD che riporta i valori medi del δ13C a quelli tipici dell’Olocene inferiore e Dryas Recente. Una tendenza verso valori più alti in entrambi i profi li isotopici contraddistingue gli ultimi 300-400 anni circa ed è verosimilmente legata ad attività antropiche (deforestazione, trasformazione a pascolo ecc.). Il forte incremento registrato nelle ultime due analisi del record del δ13C, che si accompagna alla variazione tessiturale prima menzionata, potrebbe testimoniare un aumento nella circolazione dell’aria in grotta a seguito della realizzazione di una galleria artifi ciale per l’ingresso dei visitatori. MC-ICPMS U/Th dating, oxygen and carbon isotopic determinations and petrographic investigations have been performed on the upper portion (72 cm) of a core, axially drilled from a large, actively growing stalagmite in “Grotta del Fiume - Grotta Grande del Vento” karst system (Frasassi Gorge, Ancona). The younger portion of the core (from 104 to 72 cm from the top), characterised by a relevant porosity with traces of dissolution, has not been analysed. The petrographic study has shown that the stalagmite almost completely consists of “elongated columnar” calcite. At 11 mm from the top there is clear evidence of a marked textural change from “elongated columnar” to dendritic. The stalagmite started to form before the Younger Dryas with an average growing rate of 227 μm/a between 9.63±1.06 and 8.84±0.49 ka and a later abrupt decrease down to 51 μm/a from 8.60±0.34 to 5.35±0.37 ka, followed by rates of 23 and 31 μm/a for the remaining 5350 years. A positive δ18O trend is evident along the axial growth axis of the speleothem (from -8.0‰ to -7.2‰), interrupted by two single negative peaks at 3.6 ka and 2.0 ka, also found in the δ13C record. The δ18O trend could be connected with a gradual warming from 12 ka up to the present times, or with a progressive decrease of the average annual precipitation and a consequent enrichment in the heavy isotope in the evaporation area (Eastern Mediterranean), as recorded at Soreq Cave (Israel). The general δ13C trend is negative until 2 ka (from -5.8‰ to -9.5‰), whereas the last 2 ka are characterised by an increase of δ13C up to the present value of -5.07‰. In particular, a very rapid increase of about 2‰ is evident from 1200 to 1350 AD, reaching the values typical of the Lower Holocene and the Younger Dryas. An increasing trend in both the isotopic records characterises the last 300-400 years and is probably due to anthropic activities. The strong increase measured in the last two δ13C analyses, connected with the above mentioned textural change, could testify for an increase of air circulation in the cave triggered by the opening of an artifi cial tunnel for the entrance of visitors.

Il metodo 230Th/234U applicato alla datazione di speleotemi. Evoluzione delle tecniche analitiche - Il metodo 230Th/234U è la tecnica di datazione più frequentemente applicata agli speleotemi. Gli speleotemi si formano nelle grotte per precipitazione dalle acque che circolano nell’ambiente ipogeo. Il metodo 230Th/234U è basato sul forte frazionamento che si realizza nell’idrosfera tra gli isotopi genitori (238U e 234U) e il loro fi glio a vita lunga, il 230Th. L’uranio è facilmente mobilizzato in ambiente meteorico, mentre il torio precipita o viene adsorbito dalla frazione detritica. Le concentrazioni di uranio e torio negli spleotemi generalmente rifl ettono le abbondanze relative nell’idrosfera. L’uranio coprecipita con il CaCO3 per liberazione di CO2, mentre il torio è essenzialmente assente e si forma in situ per decadimento radioattivo. Se una componente detritica è associata alla fase autigena (CaCO3), una quantità signifi cativa di torio, che non proviene dal decadimento dell’uranio, sarà presente nel sistema. L’entità di questa contaminazione può essere valutata e corretta con l’ausilio di diversi schemi di correzione che sono presentati. Segue una breve descrizione delle tecniche analitiche (spettrometria alfa, spettrometria di massa a termoionizzazione e spettrometria di massa con sorgente al plasma) e una loro evoluzione nel tempo The 230Th/234U method is the most widely-used dating technique applied to speleothems. Speleothems are bodies of mineral material formed in caves as the result of chemical precipitation from groundwater fl owing or dripping in a cave. The 230Th/234U dating is based on the extreme fractionation of the parent isotopes (238U and 234U) from their long-lived daughter 230Th in the hydrosphere. Uranium is readily mobilised in the meteoric environment, whereas thorium is easily hydrolised and precipitated or adsorbed on detrital particulates. U and Th concentrations in speleothems generally refl ect relative abundances in the hydrosphere. Uranium is co-precipitated with CaCO3 on exsolution of CO2, while thorium is essentially absent and forms in situ by radioactive decay of co-precipitated U. If a detrital component is associated with the authigenic phase of calcite, a signifi cant amount of thorium (not produced by radioactive decay of uranium) is present. The extent of this Th contamination can be corrected using different approaches which are presented here. A short description of analytical techniques (alpha spectrometry, thermal ionization mass spectrometry and inductively coupled plasma mass spectrometry) and their evolution follows.

Along the eastern coast of Mallorca, many littoral caves partly filled with brackish waters occur. The most peculiar aspect of these caves is the presence of abundant phreatic overgrowths formed on pre-existing supports located at the underground pools’ water table, which corresponds to the present sea level. Besides a specific geomorphological interest, these subaqueous speleothems provide an excellent record of Quaternary sea level stands. The clear relation between phreatic speleothem growth and the contemporary sea level allows the control of the tectonic evolution of an area, by comparing speleothems’ ages and heights with the regionally established eustatic curves. In the studied region different altimetric positions of coeval phreatic speleothems suggest the existence of a recent tectonic activity. The characteristics and chronology of this tectonic event are the objectives of this paper, pointing out at the same time the potential of phreatic speleothems in structural geology investigations. Along the coastline of the studied area, alignments of phreatic speleothems attributed to high sea stands 5a, 5c and 5e are recorded at increasing elevations northwards. This is an evidence of a significant tectonic tilting that took place, at least partially, after substage 5a because phreatic speleothems of this substage are now located at different altitudes. Considering that tectonic tilting has been continuous from post-substage 5a (approximately 85 ka) until now, and that normal displacement is approximately of 1.5 m, the average minimum velocity of the tilting can be estimated about 0.02 mm/year in the southern part with respect to the north end. Data obtained from phreatic speleothems have been compared with other regional, stratigraphical, geomorphological and tectonic evidence that all together point to the same existence of the postulated tectonic tilting. Consequently, phreatic speleothem investigation results in a new method that allows the quantification of average velocities of tilting as well as other tectonic movements with high precision. This methodology can be extended to any littoral karstic landscape where phreatic speleothems are present.

The results of isoleucine epimerization ratios in pelecypods (Glycymeris sp., Arca sp. and Cerastoderma sp.) and U-series dating of bivalves and Cladocora caespitosa sampled from different Late Pleistocene units in the Ch!eradi Islands and in the coastal areas of Mar Piccolo and Mar Grande near Taranto (Apulia region, Italy) are presented. U-series measurements on pelecypods and on corals directly associated with mollusc samples provide an independent calibration of amino acid data. The D=L ratios of isoleucine show a strong correlation with age, and thus may be considered as a predictive dating technique. This correlation also supports the reliability of U-series ages obtained for molluscs. These results, including the stratigraphic position, the lithological lateral continuity, the morphological evidence and the palaeontological characteristics of the various units, made it possible to attribute them to different marine trangressive phases referable to oxygen isotope stages (OIS) 5e–c, 5a and 3. No evidence of land emersion between OIS 5e and 5c has been found in the area. Pinkish/red sands deposits located above present sea level (B1m) have been referred to OIS 3. The Late Pleistocene morphological evolution and uplift of a complex area between the Apulian foreland and the Bradanic foredeep have been reconstructed. Due to the lack of incontestable indicators of past sea level stands the facies analysis has been performed on U-series dated 89.8 ka, OIS 5c shoreline north of Mar Piccolo and an uplift rate ranging from 0.21–0.27 mm/yr has been calculated.

Six travertine bodies outcropping along the Middle Velino Valley (Central Italy) have been studied and dated using the U/Th method in order to obtain new chronological constraints for the recent geological evolution of the area. The lithological and sedimentological characteristics of travertines have been described,showing that such deposits can be referred to waterfall,pool terraces and gentle slopes environment. Travertines have formed during warm periods and can be referred to marine oxygen isotope stages 5,3 and 1. Travertine deposition seems to stop around 5 ka BP according to other European and Italian sites. Pollen stratigraphy and ostracod assemblages from the close sequence of Valle di Castiglione,characterized by the same climatic conditions of Velino Valley, have confirmed that periods of Velino Valley travertine deposition were effectively characterized by warm and wet climatic conditions. Seismic activity strongly active in the area since the Middle Pleistocene has deeply influenced the location and the discharge of springs which have deposited the travertines,influencing in turn the shape and size of travertine bodies.

A geological, geomorphological and topographical survey has been carried out, together with the air photo interpretation and the analysis of topographic maps (1:5000 scale) along the Licosa cape promontory. Four different orders of well-preserved wave-cut terraces are identified at 20-25, 6.5 -10, 5 and 1,5 m. asl. respectively. The relative age of these four orders of marine terraces can be inferred on the basis of their correlation with the morphostratigraphical data coming from the surrounding area of S.Maria bay (northen boundary) and Ogliastro bay (southern boundary) that has been studied in a previous paper (CINQUE ET AL. 1994). Particularly the highest order can be ascribed to the end of the middle Pleistocene, oxygen isotope stage (OIS) 7, while those located at lower altitude seem to correlate quite well with the main sea level high stands of the OIS 5 (5e, 5c and 5a respectively). To test these hypotheses we try to obtain data from U-series dating of the few marine deposits we found associated with the +5 wave-cut terrace and for this aim an accurate sampling of the biogenic calcilutitic deposits has been carried out. These deposits consist of two basic components: a first detrital phase, more or less bioclastic, and another biogenic mainly formed by crusts of coralline algae with minor bryozoans. This represents a first attempt to apply U-series disequilibrium method to algae samples. The present authors believe that a rigorous protocol must definitely be followed in sample selection and preparation and independent evidences must confirm the reliability of U-series ages. By means of cursory petrographic examination, we have selected the sample for radiometric analysis that contained the thicker red algae crusts. Very thin slices (around 0.5 cm) have been cut with an ordinary saw; these have been then broken to isolate fragments consisting almost uniquely of algal crust. In this way we have tried to keep to the minimum the contamination by the calcite cements. The fibrous carbonate in the conceptacula is apparently very early in origin and should not introduce a significant error in the dating. The red algae sample was then cut into thin sections with a small diamond. Any sections was broken into several-millimetre-diameter pieces with a stainless-steel chisel. The fragments were accurately examined under a binocular microscope and any pieces that showed signs of secondary alteration were discarded. Sampling was rigorously restricted to areas dominated by talli of encrustant red algae. Areas with trace of detritus (rich in quartz, mica and feldspar grains), bioclatic fragments (bivalvia, anellida, foraminifera, echinodermata and bryozoa) and post-depositional carbonate cement were discarded. The remaining pieces were ultrasonically cleaned in distilled water twice. The U-series dating of the red algae has given an age of 102 +/- 4 ky which is in agreement with the morphostratigraphical data and can be accepted as real Some considerations have been added related to the altitude of the various orders of wave-cut terraces and the paleo-sea level eustatic curve reconstructed in other area of the Mediterranean basin. For what concern the sea level fluctuations of the last interglacial (substage 5e) recordered in Licosa cape, we underline the occurrence of two paleo sea level, respectively testified by the terraces of +9 and +6.6 m, that resembles the behaviour of the sea level during the substage 5e reconstructed in several mediterranean and extra-mediterranean coast. Moreover we established that the Licosa headland can be considered tectonically stable since the substage 5a, i.e. during the last 70 ka.

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The Montirone is a travertine-made hill (max. height 15.75 m a.s.l.) located in the Abano Terme area of the Euganean Geothermal Field (EGF), that extends on a plain band of 36 km² south of Padova (Veneto-Italy). The existence of an extensional relay zone, buried hundred meters beneath the alluvial cover, between segments of the Schio-Vicenza fault system (SVFS) has been proposed. This structure accommodates a local extensional regime that keeps open fractures in the subsurface of EGF and enhances the uprising of hot waters. The temperature of thermal waters, used mainly for spa, ranges from 60°C to 86°C. ³H and ¹⁴Cmeasurements suggest a residence time greater than 60 years, probably a few thousand years. At present, about 250 wells are active and the total average flow rate of exploited thermal fluids is 15 Mm³/y. Until the 1960, the only natural occurrence of thermal waters in Abano was located on the Montirone hill ; hot waters fed several pools located on the flat top and at the base of the hill and were partially channelled to move a mill-wheel. The intense exploitation of thermal waters, linked to the increasing number of thermal wells, lowered the potentiometric level from more than 16 m a.s.l. to -15 m a.s.l. (year 1982 ; at present is 5 m a.s.l.) and dried up the hot springs. The hill has a sub-circular shape, covers an area of 10000 m² and can be classified as a regular shaped travertine mound. The mound is affected by a network of fractures mainly composed of two sets (WNW-ESE and NNE-SSW) that can be interpreted as a fracture mesh developed in a dilational stepover between strike-slip or transtensional fault segments of the SVFS. The trend of fissures parallels the trend of the main regional structural elements (e.g. SVFS ; mainly oriented NW-SE) and is consistent with the direction of the anisotropy depicted in the variogram analysis of transmissivity calculated in the bedrock of EGF(N110°E). Two drillings (about 1m deep) were made to study the depositional facies of the travertine because of the absence of relevant cross sections. Thin sections of the core samples show the dominance of layered travertine made of lime-mudstone with paper-thin rafts and laminae of bacterial shrub, locally covered by crystalline crusts made of feather-like calcite. Moreover, soft sediment syn-depositional deformations and repeated phases of karstic dissolution and redeposition have been observed. Isotopic analyses on uranium-series, carried out on crystalline crusts sampled during the drillings, have given ages from 30±4 kY to 25±5 kY. Moreover, the low content of U (from 3 to 12 ppb) and the high activity ratio of 234U/238U (>2) clarify the high interaction between rock and water, typical of a deep geothermal system with high residence time of waters. Geophysical methods, and particularly Electromagnetic survey (EM) and Electrical Resistivity Tomography (ERT) were used to determine the mound geometry. The map of EM measurements (depth of investigation around 1.5m) shows the presence of two resistive areas along the slope and a more conductive region on the top of the mound. The latter can be interpreted as indicative of the uprising of thermal waters through a more fractured zone. ERT surveys confirm the vertical extent of the conductive and resistive anomalies, and support the interpretation above. The presence of the Montirone travertine deposit strongly supports the existence of a releasing structure in the subsurface, which controls the development of the EGF, and an ongoing activity of the SVFS, which is generally considered inactive. The analysis on U-series isotopes gives another important constraint on the deep circulation and a long residence time of thermal waters.

The southern and southeastern rim of the present caldera (La Fossa caldera) at Vulcano Island (Aeolian Islands, Italy) is crosscut by a network of fractures filled with calcite and minor chalcedony. Fluid inclusion studies indicate that both mineral phases were deposited from hydrothermal solutions. Several calcite samples were analyzed and their U, Sr, Nd, O and C isotopic composition was determined. UTh geochronological data suggest two discrete depositional episodes: one at 50 ka (southern rim) and the other at 25 ka (southeastern rim). Oxygen isotopic compositions, 87Sr/86Sr and 234U/238U ratios exclude that seawater was involved significantly in the hydrothermal system, in agreement with fluid inclusion studies which did not document the presence of NaCl. The Nd and Sr isotopic composition of calcite reflects the composition of the host rocks. The oxygen isotopic composition excludes a post-depositional interaction with meteoric water and suggests a depositional temperature consistent with that obtained from the fluid inclusion study (160–170 °C), assuming equilibrium conditions and a fluid isotopic composition close to present-day steam emissions. The positive correlation between U content and C isotopic composition indicates a rapid change in CO2 pressure during calcite deposition. This observation is consistent with a rapid fluid ascent, likely connected to two phases of collapse of the La Fossa caldera. The ages of the calcites which fill the fractures at the La Fossa caldera indicate the activation time of the fracture systems which, in turn, are connected to the above mentioned phases of the caldera collapse.

Sea level changes during Last Interglacial (substage Se) have been documented in two sites of the Western Mediterranean area: Mallorca Island (Balearic Archipelago) and Capo Caccia area (NW Sardinia). Past sea stands have been recorded by overgrowths of phreatic crystallizations developing around previously formed vadose speleothems. These carbonate coatings have been U-series dated, mostly using multicollector inductively coupled mass spectrometry. Two high sea stands have been recognised along the eastern coast of Mallorca at about 1.5 - 3 metres a.p.s.l, from 135 to 109 ka B.P., with a rapid episode of regression around 125 ka. The average duration of the older high stand episode can be estimated at 9.5 ka and that of the younger at 12.8 ka. So far only the younger stand has been found in Capo Caccia area at 4.3 m a.p.s.l., with a minimum duration of 3 ka. The difference in elevation of late Se high stand, recorded at Mallorca and Capo Caccia, can be only partly justified by neotectonic activity and is probably the result of different responses of the two areas, (owing to their different crustal thickness) to the change in the water loading characterising the glacial-interglacial cycles., Els canvis del nivell de la mar durant el darrer interglacial (subestadi isotòpic Se) han estat documentats en dues àrees de la Mediterrània occidental: l'illa de Mallorca (Illes Balears) i la zona de Capo Caccia, a I' Alguer (NW de Sardenya). A les coves costaneres d'aquestes illes, antigues estabilitzacions del nivell marí es troben enregistrades mitjançant sobrecreixements de cristal·litzacions freàtiques que es desenvoluparen al voltant d'espeleotemes vadosos preexistents. Aquests recobriments de carbonats s'han datat amb el mètode de les sèries de l'Urani, majoritàriament usant tècniques MC-ICPMS (multicollector inductively coupled mass spectrometry). Al llarg de la costa oriental de Mallorca, ha estat possible reconèixer dos episodis transgressius que assoleixen 1,5 - 3 m per sobre de I' actual nivell marí, ocorreguts entre 135 i 109 ka BP, separats per una ràpida regressió al voltant dels 125 ka. La durada de la pulsació transgressiva més antiga pot ésser estimada en 9,5 ka, mentre que la duració de la més recent seria de 12,8 ka. Fins al moment, tans sols la transgressió més recent es troba documentada a l'àrea de Capo Caccia a +4,3 m amb una durada mínima de 3 ka. La diferència d'altitud de l'episodi transgressiu més recent dins el subestadi Se, enregistrat a Mallorca i a Capo Caccia (Sardegna), pot ésser tan sols parcialment justificada per l'activitat neotectònica i és probablement el resultat de respostes diferents de les dues àrees (atribuïbles a les distintes gruixes de l'escorça continental) als canvis en la càrrega d'aigua marina que caracteritzen els cicles climàtics pleistocènics.

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A method for determining the ages of shoshonitic volcanics erupted within the last 5000 years is presented and assessed. This method is based on 226Ra/230Th radioactive disequilibrium and on a leaching procedure and γ-counting of volcanics containing Th-enriched, Rainitial-depleted mineral phases detected by microprobe analyses. K is used as a Ra-stable chemical analogue. The data are plotted on (226Ra/228Ra)− K(228Ra) Osmond-type diagrams in order to evaluate the 226Raradiogenic230Th activity ratio of the Th-enriched, Rainitial-depleted phases. Four samples of volcanics from Vulcano Island (southern Italy) gave ages consistent with historical reports andK/Ar chronology.

Chronological measurements have been carried out on speleothems from the Grotta del Fiume-Grotta Grande del Vento karst system in Frasassi (Ancona, Italy) by means of the 230Th radiometric method in order to date hypogean karst levels and related geological events. Higher levels were found to be older than the lower ones according to standstills and sinkings of the water table. The dated speleothems from the first and second level formed less than 10,000 years ago; the minimum ages of the third and fifth levels, which are respectively 130,000 and 200,000 years old, were correlated to climatic events. Dating different portions of a speleothem allows the measurements of the radial and vertical accretion rates and their variation over time. Such data together with the 234U/238U activity ratio and the uranium content of the speleothems have been correlated with the climatic variations connected to the glacial cycles. The same data have been used to fit a hydrogeological model.