Rapolano Terme Research Articles

Travertine depositional systems of Central Italy: Rapolano Terme and the Acque Albule Basin. An overview of geometries and lithofacies associations of the depositional setting

Travertine depositional systems of Central Italy: Rapolano Terme and the Acque Albule Basin. An overview of geometries and lithofacies associations of the depositional setting

Effectiveness of Vascular Balneotherapy in the Treatment of Chronic Venous Disease (CVD)

Aim: Inside the “Antica Querciolaia” Thermal Station, located in the municipality of Rapolano Terme (Siena), there is a well, called “Well 5 – Cold Bath”, from which gushes a homeothermic alkaline bicarbonate-sulphate mineral water, considered suitable for thermal use with venous vascular address. The main endpoint of the study was to demonstrate the effects of vascular balneotherapy with thermal mineral water on classical symptoms, such as edema and quality of life of patients with chronic venous disease in the lower limbs, while the secondary endpoint was to verify the efficacy and tolerability of vascular balneotherapy carried out in predefined vascular paths and with a standardized protocol. Materials and Methods: In the double-blind, randomized controlled study, 60 patients with chronic venous disease of the lower limbs were enrolled in the first three stages of the CEAP classification. The patients were divided into two equivalent groups: “Balneotherapy Group”, treated with baths in thermal mineral water from “Well 5 – Cold Bath” and venoactive drug therapy and “Control Group” which only took drug therapy in an equivalent dose and duration. Results: The results of the study show a clear improvement of the “Balneotherapy Group” compared to the “Control Group” in the treatment of chronic venous disease of the lower limbs, concerning both the primary and secondary endpoints set by the study. Conclusions: Our findings show the undoubted efficacy and excellent tolerability of vascular balneotherapy in the treatment of chronic venous disease of the lower limbs.

Comunità di mestiere: percorso etnografico sulle cave di travertino di Rapolano Terme

Building on ethnographic research, this article focuses on briefly presenting the history of social, economic and cultural changes of the sienese travertine extraction and transformation in the Rapolano Terme stoneworking district. The research is based on findings from interviews with quarrymen and stoneworkers, key photographs and documents contained in a variety of archives, which together provide an overall view of the narrative of this territorial identity. The aim of the text, as the author points out, is to look at how the craft continuity and transmission changes contribute to current processes of heritagisation built on the connections between economic potential, history, art, and skilled labour.

Key travertine tectofacies for neotectonics and palaeoseismicity reconstruction: effects of hydrothermal overpressured fluid injection

Travertine deposits have long been considered as powerful tools for investigating neotectonics and reconstructing palaeoseismic events. We document, for the first time, the effects of overpressured hydrothermal fluids injected within travertine deposits. We also describe tectofacies interpreted as a consequence of coseismic events. Calcite veins, banded or massive, associated with hydrofracture and fluid-escape features, promoted hydrothermal eruptions and lithoclast formation in latest Quaternary travertine exposed in two quarries near Rapolano Terme (Northern Apennines, Italy). The isotopic composition of the calcite veins confirms the hydrothermal origin of the parent fluids and their rapid ascent, as indicated by the estimated palaeo-temperatures (43–50°C). Integration of U–Th ages obtained for the calcite veins with palaeoseismic evidence from a local archaeological site built at the top of one of the analysed travertine deposits suggests that hydrofracture and fluid-escape structures were associated with five main seismic events that occurred from the latest Pleistocene to the fourth century AD. In sum, the travertine tectofacies have a key role in better constraining the seismotectonic setting of a region and thus offer a powerful tool for the evaluation of seismic hazard for areas characterized by low seismicity and travertine deposition.

Various morphological types of thermogenic travertines in Northern Euboea and Eastern Central Greece

In the northern part of Euboea Island and the neighbouring part of the mainland in eastern central Greece, many hot springs exist and some of them create travertine deposits. The objectives of the study were to identify and describe the various morphological types of the thermogenic travertine deposits. The samples were studied at the lab with optical microscopy, X-Ray Diffraction, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS), in order to verify their main mineralogical composition and their mineral chemistry. The studied travertine deposits consist mainly of aragonite and calcite, but in some cases, as main mineral phase, an amorphous hydrous ferric oxyhydroxide (ferrihydrite), was also identified. The morphological types that were identified were of great variety (mounds, travertine caves etc) and some of them were quite rare (cascades, remora etc). Morphological data and field observations suggest possible inorganic and organic controls on carbonate precipitation. Similar morphological types have been recorded at large travertine systems like Mammoth hot springs, Yellowstone National Park in USA and at Rapolano Terme, Italy.

Low Angle Normal Fault (LANF)-zone architecture and permeability features in bedded carbonate from inner Northern Apennines (Rapolano Terme, Central Italy)

Fault zones have the capacity to be hydraulic conduits within upper crustal levels, allowing migration of large volume of fluids through shallow and deeper geological environments. Low-angle normal faults (LANFs) crosscutting carbonate rocks produce damaged volumes that may have a relevant role in channelling or hosting geothermal fluids, therefore deserving of investigation to better predict mining targets. Deformation along LANFs zones, dissecting carbonate successions, produces permeable volumes presently exploited in the Larderello and Monte Amiata geothermal areas (Italy). In this paper, the architectural and permeability features of an exhumed LANF-zone exposed in the Northern Apennines, (Rapolano Terme, central Italy), affecting Cretaceous bedded limestone, are presented. Such a fault was not affected by circulation of geothermal fluids, but its features could reveal much on the potential impact on fluids migration in the active geothermal areas, therefore resulting an intriguing analogue. The study LANF-zone consists of faults, which enucleated at depth >4km. During its earlier stage of evolution, dissolution seams, often arranged in s–c fabric, characterised the whole damage zone. Dissolution seams developed under very low-grade metamorphism (T=100–150°C) as indicated by illite crystallinty analyses. Fault zone architecture and permeability features changed during the fault growth and exhumation. Permeability heterogeneity and anisotropy characterised the LANF zone during its development. If geofluids circulated within the fault zone, it could be an effective barrier during its earlier evolution, being accompanied by dissolution seams. On the contrary, it could play as combined barriers–conduits during its later evolution (progressively at shallower levels) being characterised by intersecting fault planes, which define pipe-like conduits parallel to the direction of the tectonic transport. Such a configuration could have the capacity to impact on fluids migration for long paths across the upper crustal levels. This adds significant information for predicting deeper geothermal circuits and the location of potential exploitable reservoirs in active tectonic environments.

Distribution, lithotypes and mineralogical study of newly formed thermogenic travertines in Northern Euboea and Eastern Central Greece

Abstract In the northwestern part of Euboea Island and the neighbouring part of the mainland in eastern central Greece, many hot springs exist. We collected and analysed the newly formed material around the hot springs. The samples were studied at the lab with X-Ray Diffraction, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). In all cases the studied materials were thermogenic travertine presenting many different lithotypes. The studied travertine deposits consist mainly of aragonite and calcite, but in some cases, as the main mineral phase, an amorphous hydrous ferric oxyhydroxide, probably ferrihydrite (creating a laminated iron-rich travertine deposit), was identified. The lithotypes that were identified were of great variety (spicular, shrubs, etc). Some of them (pisoliths, rafts and foam rock types) are quite rare and one of them (framework type) is described for the first time. Morphological data and field observations suggest possible inorganic and organic controls on carbonate precipitation. Similar lithotypes have been recorded at Mammoth hot springs, Yellowstone National Park in USA and at Rapolano Terme, Italy.

Geologia dell’area di Rapolano Terme in Provincia di Siena (Appennino Settentrionale)

Geologia dell’area di Rapolano Terme in Provincia di Siena (Appennino Settentrionale)

Short- and Long-Term Effects of Spa Therapy in Knee Osteoarthritis

To assess both the short- and long-term effectiveness of spa therapy in patients with primary knee osteoarthritis in a prospective, randomized, single-blinded, controlled trial. Eighty outpatients were enrolled in this study; 40 patients were treated with a combination of daily local mud packs and bicarbonate-sulfate mineral bath water from the spa center of Rapolano Terme (Siena, Italy) for 2 wks, and 40 patients continued regular, routine ambulatory care. Patients were assessed at baseline time; after 2 wks; after 3, 6, and 9 mos after the beginning of the study and were evaluated by Visual Analog Scale for spontaneous pain, Lequesne index, Western Ontario and McMaster Universities Index for gonarthrosis, Arthritis Impact Measurement Scale-1, and symptomatic drug consumption. We observed a significant improvement of all evaluated parameters at the end of the cycle of spa therapy, which persisted throughout the whole of the follow-up period, whereas in the control group no significant differences were noted. This symptomatic effect was confirmed by the significant reduction of symptomatic drug consumption. Tolerability of spa therapy seemed to be good, with light and transitory side effects. The results from our study confirm that the beneficial effects of spa therapy in patients with knee osteoarthritis lasts over time, with positive effects on the painful symptomatology and a significant improvement on functional capacities. Spa therapy can represent a useful backup to pharmacologic treatment of knee osteoarthritis or a valid alternative for patients who do not tolerate pharmacologic treatments.

Nuovi dati litostratigrafici e biostratigrafici sulla Scaglia Toscana nella Toscana meridionale (area di Rapolano Terme)

Nuovi dati litostratigrafici e biostratigrafici sulla Scaglia Toscana nella Toscana meridionale (area di Rapolano Terme)

Travertine deposition and faulting: the fault-related travertine fissure-ridge at Terme S. Giovanni, Rapolano Terme (Italy)

In this paper we describe an example of travertine fissure-ridge development along the trace of a normal fault with metre displacement, located in the eastern margin of the Neogene–Quaternary Siena Basin, in the Terme S. Giovanni area (Rapolano Terme, Italy). This morphotectonic feature, 250 m long, 30 m wide and 10 m high, formed from supersaturated hot waters (39.9°C) flowing from thermal springs aligned along the trace of the normal fault dissecting travertines not older than Late Pleistocene (24 ± 3 ka). A straight, continuous fissure with a maximum width of 20 cm occurs at the top of the ridge, along its crest. Hot fluids flow from cones mainly located at the extremities of the ridge, where travertine is depositing. The travertine fissure-ridge shows an asymmetrical profile since it buries the fault scarp. The difference in height of slopes corresponds to the vertical displacement of the normal fault. Fissuring of the recent travertine deposits along the strike of the crestal fissure, as well as recent hydrothermal circulation, lead us to believe that the Terme S. Giovanni normal fault may be currently active. On the whole, the Terme S. Giovanni fissure ridge can be defined as a travertine fault trace fissure-ridge, adding a helpful example for studying the relationship between faulting and travertine deposition.

Hot spring travertines in the Rapolano Terme area, Toscany, central Italy

Hot spring travertines in the Rapolano Terme area, Toscany, central Italy

The Effect of Elevated Atmospheric CO2 Concentration on Two Populus Clones Grown in a FACE System

SUMMARY Two poplar clones, hybrid Populus deltoides Bartr. Ex Marsh X Populus nigra L. (Populus xeuramericana), clone I-214, and Populus deltoides, clone Lux, were grown from hardwood cuttings for one growing season in either ambient (360 μmol mol−1) or elevated (560 μmol mol−1) [CO2] in FACE-systemrings at Rapolano Terme (Siena, Italy). Both clones I-214 and Lux exhibited a higher aboveground bio-mass, photosynthesis at light saturation and instantaneous transpiration efficiency (ITE) in CO2-enriched air. The elevated [CO2]-induced responses of clone I-214 included increased investment in branch and leaf biomass, and enhanced stem volume. The elevated [CO2]-induced responses of clone Lux included an increase in the number of branches (and foliage area). Indication of photosynthetic acclimation under elevated [CO2] was found during the early morning, but only in clone I-214. Stomatal conductance decreased under elevated [CO2] particularly in clone Lux. Clone differences in response to elevated [CO2] should be taken in account when planning future poplar plantations in forecast warmer and drier Mediterranean sites.

Faults linkage, damage rocks and hydrothermal fluid circulation: Tectonic interpretation of the Rapolano Terme travertines (southern Tuscany, Italy) in the context of Northern Apennines Neogene-Quaternary extension

The tectonic history of Neogene-Quaternary extensional structures has been documented in the inner part of the Northern Apennines (Rapolano Terme area) from Quaternary travertines and faults relationships. In particular, structural studies, field mapping and tectono-stratigraphical considerations on the pre-Neogene, Pliocene and Quaternary units indicate two fault populations of different ages. The travertines, broadly exposed in the Rapolano Terme area, were related to hydrothermal fluid circulation and upwelling along the damage zones of Pleistocene normal faults. These structures were superimposed upon normal (mainly NNW–SSE and SW–NE oriented) and transtensional (mainly SW–NE oriented) faults, Early–Middle Pliocene in age, related to development of the Siena Basin. The age of such Pliocene normal and transtensional faults has been inferred on the basis of the relationships between tectonic elements and Pliocene deposits. In fact, Middle Pliocene marine sandy and gravelly sediments suture the faults. The Pleistocene normal faults (mainly SW–NE oriented) reactivated the oldest SW–NE transtensional faults, cut the NNW–SSE normal faults, and displaced Middle Pliocene marine deposits. Pleistocene-Holocene travertines and present-day thermal springs mainly occur at the intersection points between the Pleistocene SW–NE faults and the Pliocene NNW–SSE normal faults, or along the SW–NE Pleistocene normal faults.

Impact of rising CO2 on emissions of volatile organic compounds: isoprene emission from Phragmites australis growing at elevated CO2 in a natural carbon dioxide spring†

ABSTRACTIsoprene basal emission (the emission of isoprene from leaves exposed to a light intensity of 1000 µmol m−2 s−1 and maintained at a temperature of 30 °C) was measured in Phragmites australis plants growing under elevated CO2 in the Bossoleto CO2 spring at Rapolano Terme, Italy, and under ambient CO2 at a nearby control site. Gas exchange and biochemical measurements were concurrently taken. Isoprene emission was lower in the plants growing at elevated CO2 than in those growing at ambient CO2. Isoprene emission and isoprene synthase activity (IsoS) were very low in plants growing at the bottom of the spring under very rich CO2 and increased at increasing distance from the spring (and decreasing CO2 concentration). Distance from the spring did not significantly affect photosynthesis making it therefore unlikely that there is carbon limitation to isoprene formation. The isoprene emission rate was very quickly reduced after rapid switches from elevated to ambient CO2 in the gas‐exchange cuvette, whereas it increased when switching from ambient to elevated CO2. The rapidity of the response may be consistent with post‐translational modifications of enzymes in the biosynthetic pathway of isoprene formation. Reduction of IsoS activity is interpreted as a long‐term response. Basal emission of isoprene was not constant over the day but showed a diurnal course opposite to photosynthesis, with a peak during the hottest hours of the day, independent of stomatal conductance and probably dependent on external air temperature or temporary reduction of CO2 concentration. The present experiments show that basal emission rate of isoprene is likely to be reduced under future elevated CO2 levels and allow improvement in the modelling of future isoprene emission rates.

Rapid facies changes in Holocene fissure ridge hot spring travertines, Rapolano Terme, Italy

Holocene hot water travertine continues to form at Terme San Giovanni, near Rapolano Terme, central Italy, although artificial diversion of the water has reduced deposition. Mesothermal water (≈38–39 °C) emerging from fault‐controlled vents located on a hilltop has created a linear fissure ridge 240 m long and up to 10 m high. Active parts of the ridge crest are covered by small cones; inactive parts are locally neotectonically fissured and have small pools. Ridge deposits include crystalline crust, paper‐thin raft and shrub lithotypes. The ridge has both smooth and terraced marginal slopes, dominated by crystalline crusts with small shrubs in terrace pools. At the base of the ridge, there is a rapid transition to lateral flats and depressions, where water from the ridge collects and deposits shrub, irregular pisoid, reed, paper‐thin raft and fine‐grained and organic‐rich travertines. Water channelled to nearby valley sides deposits thick crystalline crusts on valley slopes and waterfall overhangs, locally with small pools filled by smooth spherical pisoids. On the valley floor, mixing of waters forms varied stream‐fill deposits that include micritic reed, paper‐thin raft and coated bubble travertines. The diversity of travertine facies observed results from the location of the Terme San Giovanni hot springs on a hill crest, thus providing a wide array of downslope locations for further deposition. The abrupt facies transitions observed are characteristic of hot spring carbonates and result from a combination of rapid decrease in precipitation away from vents, variations in local surface topography and the feedback effect of travertine deposition itself, which dams and diverts water flow.

Hot‐spring travertine facies and sequences, Late Pleistocene, Rapolano Terme, Italy

Late Pleistocene travertines up to 40 m thick near Rapolano Terme in Tuscany, central Italy, were precipitated by hot water issuing from springs on hillsides and flowing into adjacent depressions to mix with rainwater. Proximal light‐coloured slope and terrace travertines pass distally into darker reed mound and depression‐fill travertines. Lithotypes include crystalline crust, shrub, pisoid, paper‐thin raft, coated bubble, reed, and lithoclast‐breccia. High precipitation rates resulted in rapid slope aggradation and progradation. Dilution by rainwater likely lowered precipitation rates in depressions, but deposition was augmented by allochthonous material eroded from upslope travertines.Slope Depositional Systems consist of Smooth and Terrace Slope facies characterized by white crystalline crusts, with diverse additional lithotypes in terrace pools. Depression Depositional Systems have mixed light and dark travertines with horizontal to gently concave stratification. Extensive light‐coloured Shrub Flat travertine is dominant; darker Marsh‐Pool Facies composed of fine lithoclast and reed travertine is localized. Reed Mounds composed of mixed light and dark travertines localized by abundant reed growth, formed where spring water emerged near the bases of low angle slopes.Distal reduction in accretion rate was the major influence on sequence development. Light‐coloured slope travertines interdigitate with darker depression deposits. Vertical aggradation of slope deposits, mound progradation, and filling of topographic depressions is expressed by advance and retreat of facies. Evolution from depression to slope or mound sequences is termed ‘steepening up’. Up‐sequence change from slope or mound to depression facies is termed ‘levelling up’. Exposure surfaces associated with palaeosols are common in all facies and often constitute sequence boundaries. They are more closely spaced in depression sequences, reflecting slower and possibly also more discontinuous accumulation at sites furthest from hot springs.

Origin and diagenesis of Quaternary travertine shrub fabrics, Rapolano Terme, central Italy

ABSTRACTMillimetre to centimetre sized arborescent shrub‐like calcite precipitates are common constituents of hot water travertine shallow pool deposits of Quaternary age at Rapolano Terme, Tuscany, Italy. In the presently forming travertines, the shrubs consist of apparently random associations of (i) micrite aggregates and (ii) subhedral to euhedral rhombic spar crystal aggregates. In thin section, the micrite aggregates appear dark and the spar‐rhomb aggregates light, giving the shrubs a mottled appearance.Travertines are basically produced by CaCO3 precipitation due to degassing and evaporation of the spring waters, although biological influence may also stimulate precipitation. The formation of masses of erect shrubs, rather than dense crystal crusts that form on slopes, is probably due to limited water flow in the pool environments.Microbes, including bacteria and diatoms, are important influences on shrub microfabric and external shape. The micrite aggregates are associated with bacteriform bodies, seen as tiny rods and spheres. The micrite precipitates around these bodies and in adjacent biofilm. Spar‐rhomb precipitation appears to be external to the biofilm, and may be related to the presence of diatoms which are locally closely associated with the spar‐rhombs, although an essentially inorganic origin, particularly for the more euhedral rhombs, cannot be ruled out.In the older Quaternary travertines, the original microfabric of the shrubs has been diagenetically altered. The original mottled appearance of the shrubs has become uniformly dark and micritic, and the evidence for the dual micritic and spar‐rhomb origin of the shrubs is obscured or destroyed. Spar‐micritization of the shrubs is probably due to abiotic, and locally biotic, dissolution. Previous studies did not recognize the diagenetic micritization and attributed shrub formation entirely to bacterial activity.

Aragonite laminae in hot water travertine crusts, Rapolano Terme, Italy

ABSTRACTSmall (5–30 μm) aggregates of aragonite needles occur in calcite crystal crusts of present day hot water slope travertines at Rapolano Terme in Tuscany, Italy. The aggregates are mainly concentrated in irregular, wispy and dark laminae which cross‐cut calcite crystal feathers to create a pervasive millimetre scale banded appearance in the deposit; they also occur less commonly scattered irregularly through the calcite layers. The aragonite needle aggregates are in the form of crosses, fascicles (sheaf shaped bundles, or dumbbell shaped), rosettes and spherulites. Locally, irregular masses of needles also occur. The fascicles, rosettes and spherulites have hollow centres which resemble microbial components (?fungal spores, bacterial colonies and pollen), suggesting that the aragonite crystals are biotically nucleated. The lamination is interpreted to reflect diurnal control. Stimulation of microbial activity during daylight concentrates cells in laminae and promotes aragonite calcification. Calcite feather crystals, although traversed by the aragonite aggregate laminae, have a clear appearance under the light microscope. They form more or less continuously through the diurnal cycle by abiotic precipitation. The constant association of aragonite with organic nuclei, irrespective of whether the latter are in laminae or scattered through the calcite layers, supports a biotic control on aragonite formation. Lamination in Pleistocene travertines is superficially similar to that in the present day deposits, but is diagenetically altered. In the Pleistocene deposits, the calcite feathers appear dark under the light microscope and the aragonite aggregates, where they are not altered to dark calcite, are dissolved, together with parts of the adjacent spar calcite, and therefore appear light coloured.

Microbial micritic carbonates in uppermost Permian reefs, Sichuan Basin, southern China: some similarities with Recent travertines

ABSTRACTThe uppermost Permian Chuenmuping reef formed on the western side of a carbonate platform situated in the eastern Sichuan Basin, southern China. Contrasts exist between this western patch reef and the better known Jiantianba barrier reef complex on the eastern platform margin in western Hubei Province, 250 km to the east. Microbial micritic carbonates form significant components of the Chuenmuping reef limestones. Three types of fabric can be identified: irregular, clotted and scalloped‐laminated. An additional, cuneiform fabric has been found only in fore‐reef facies at Jiantianba.Irregular fabric is comparable with the surface of presently forming travertines at Rapolano Terme, central Italy, which are produced by calcification of cyanobacteria. Clotted fabric shows indistinct peloids which tend to lack rims, and are amalgamated into irregular masses, some of which exhibit bush‐like arrangements where traces of filaments can be seen. Traces of filaments are observed in both dark and light layers in the scalloped‐laminated fabric, again suggesting a microbial origin. Cuneiform fabric consists of peloids and filaments, and closely resembles deposits in Quaternary travertines which may have been caused by bacterial action.Chuenmuping reef shows a shallowing sequence in normal marine conditions. The micritic fabrics interpreted here as microbial occur more commonly in the upper part of the reef. This indicates that microbial micrites, with a cementing role, formed coevally with reef growth within the upper part of the photic zone.