23 research outputs found
Grotta Romanelli (Southern Italy, Apulia): legacies and issues in excavating a key site for the Pleistocene of the Mediterranean
Grotta Romanelli, located on the adriatic coast of southern apulia (Italy), is considered a key site for the Mediterranean Pleistocene for its archaeological and palaeontological contents. The research team had to deal with the consequences of more than 40 years of inactivity in the eld and the combined effect of erosion and legal, as well as illegal, excavations. In this paper, we provide a database of all the information published during the rst 70 years of excavations and highlight the outstanding problems and contradictions between the chronological and geomorphological evidence, the features of the faunal assemblages and the limestone artefacts
Using a scale model room to assess the contribution of building material of volcanic origin to indoor radon
AbstractIn the frame of Radon rEal time monitoring System and Proactive Indoor Remediation (RESPIRE), a LIFE 2016 project funded by the European Commission, the contribution of building materials of volcanic origin to indoor radon concentration was investigated. First, total gamma radiation and related outdoor dose rates of geological materials in the Caprarola area (Central Italy) were measured to define main sources of radiation. Second, 222Rn and 220Rn exhalation rates of these rocks used as building materials were measured using an accumulation chamber connected in a closed loop with a RAD7 radon monitor. Among others, the very porous "Tufo di Gallese" ignimbrite provided the highest values. This material was then used to construct a scale model room of 62 cm × 50 cm × 35 cm (inner length × width × height, respectively) to assess experimental radon and thoron activity concentration at equilibrium and study the effects of climatic conditions and different coatings on radon levels. A first test was carried out at ambient temperature to determine experimental 222Rn and 220Rn equilibrium activities in the model room, not covered with plaster or other coating materials. Experimental 222Rn equilibrium was recorded in just two days demonstrating that the room "breaths", exchanging air with the outdoor environment. This determines a dilution of indoor radon concentration. Other experiments showed that inner covers (such as plasterboard and different kinds of paints) partially influence 222Rn but entirely cut the short-lived 220Rn. Finally, decreases in ambient temperature reduce radon exhalation from building material and, in turn, indoor activity concentration
Relationships between geogenic radon potential and gamma ray maps with indoor radon levels at Caprarola municipality (central Italy)
Exposures to relatively high indoor radon (222Rn) levels represents a serious public health risk because Rn is
associated with lung cancer (Darby et al., 2001; WHO, 2009; Oh et al., 2016; Sheen et al., 2016). The risk is high
because radon, and its short-lived decay products in the atmosphere, contributes for about 60% of the total annual
effective dose (UNSCEAR, 2000; WHO, 2009). Cancer risk is increased by smoking being almost 9 times higher
than the risk to non-smokers exposed to similar levels (EPA, 2009). Due to these reasons, it is very important to
assess the indoor exposure of public to radon and their daughters. Rn is a natural ubiquitous gas and its abundance
is mainly controlled by the geology, and in particular by the soil and rock content of its parent nuclide (238U).
Furthermore, bedrock characteristics (i.e. permeability and porosity) and also fault activity can affect the amount
of Rn released in the ground (Ciotoli et al., 2007; Barnet et al., 2018). As such, in conditions of permeable and/or
fractured bedrock and high uranium content, high indoor radon concentrations are expected (Bossew and Lettner,
2007; Gruber et al., 2013; Cinelli et al., 2015; Ielsch et al., 2017; Ciotoli et al., 2017). A non-natural contribution
that controls the indoor Rn levels is home construction type and building materials (Vauptic et al., 2002; Appleton,
2007). Additionally, meteorological factors, such as wind, temperature and humidity, can affect the rate of Rn
entry into the buildings (Porstendörfer et al., 1994; Miles et al., 2005; Schubert et al., 2018).
In this work, we propose a new geospatial technique to construct the geogenic radon potential (GRP) map of the
Caprarola municipality (northern Lazio, central Italy) characterized by recent (about 100 Kyr) volcanic deposits
with high content in radon parent nuclides (Ciotoli et al., 2017). GRP map has been obtained by using Empirical
Bayesian Kriging Regression (EBKR) technique with soil gas radon, as the response variable, and a number
of proxy variables (i.e. content of the radiogenic parent nuclides, the emanation coefficient of the outcropping
rocks, the diffusive 222Rn flux from the soil, the soil-gas CO2 concentration, the Digital Terrain Model (DTM),
the permeability of the outcropping rocks and the gamma dose radiation of the shallow lithology. Furthermore,
possible relationships between predicted soil radon values (i.e. GRP) and gamma radiation distribution with the
indoor concentrations measured in private and public buildings has been investigated, respectively. The obtained
results confirm that GRP maps provide the local administration of a useful tool for land use planning and that, the
mapping of gamma emission, allows to a fast and effective evaluation of indoor radon hazard because it is mainly
influenced by the building materials rather than other anthropic controls
European Atlas of Natural Radiation
Natural ionizing radiation is considered as the largest contributor to the collective effective dose received by the world population. The human population is continuously exposed to ionizing radiation from several natural sources that can be classified into two broad categories: high-energy cosmic rays incident on the Earth’s atmosphere and releasing secondary radiation (cosmic contribution); and radioactive nuclides generated during the formation of the Earth and still present in the Earth’s crust (terrestrial contribution). Terrestrial radioactivity is mostly produced by the uranium and thorium radioactive families together with potassium. In most circumstances, radon, a noble gas produced in the radioactive decay of uranium, is the most important contributor to the total dose.
This Atlas aims to present the current state of knowledge of natural radioactivity, by giving general background information, and describing its various sources. This reference material is complemented by a collection of maps of Europe displaying the levels of natural radioactivity caused by different sources.
It is a compilation of contributions and reviews received from more than 80 experts in their field: they come from universities, research centres, national and European authorities and international organizations.
This Atlas provides reference material and makes harmonized datasets available to the scientific community and national competent authorities. In parallel, this Atlas may serve as a tool for the public to:
• familiarize itself with natural radioactivity;
• be informed about the levels of natural radioactivity caused by different sources;
• have a more balanced view of the annual dose received by the world population, to which natural radioactivity is the largest contributor;
• and make direct comparisons between doses from natural sources of ionizing radiation and those from man-made (artificial) ones, hence to better understand the latter.JRC.G.10-Knowledge for Nuclear Security and Safet
European Atlas of Natural Radiation
Natural ionizing radiation is considered as the largest contributor to the collective effective dose received by the world population. The human population is continuously exposed to ionizing radiation from several natural sources that can be classified into two broad categories: high-energy cosmic rays incident on the Earth’s atmosphere and releasing secondary radiation (cosmic contribution); and radioactive nuclides generated during the formation of the Earth and still present in the Earth’s crust (terrestrial contribution). Terrestrial radioactivity is mostly produced by the uranium and thorium radioactive families together with potassium. In most circumstances, radon, a noble gas produced in the radioactive decay of uranium, is the most important contributor to the total dose.This Atlas aims to present the current state of knowledge of natural radioactivity, by giving general background information, and describing its various sources. This reference material is complemented by a collection of maps of Europe displaying the levels of natural radioactivity caused by different sources. It is a compilation of contributions and reviews received from more than 80 experts in their field: they come from universities, research centres, national and European authorities and international organizations.This Atlas provides reference material and makes harmonized datasets available to the scientific community and national competent authorities. In parallel, this Atlas may serve as a tool for the public to: • familiarize itself with natural radioactivity;• be informed about the levels of natural radioactivity caused by different sources;• have a more balanced view of the annual dose received by the world population, to which natural radioactivity is the largest contributor;• and make direct comparisons between doses from natural sources of ionizing radiation and those from man-made (artificial) ones, hence to better understand the latter.Additional information at: https://remon.jrc.ec.europa.eu/About/Atlas-of-Natural-Radiatio
Applications of Sr isotopes and U-series radionuclides to the hydrogeology of Sangemini area (Terni - Central Italy)
Sr isotopes and U series radionuclides in the Sangemini area (Central Italy): Hydrogeology implications
The strontium isotopic ratio (expressed as 87Sr/86Sr) of groundwater represents a useful method for studying and understanding the groundwater circulations, also, the U and Ra isotopic compositions can vary as function of the groundwater residence time.
This paper reports an evaluation of the probable recharge area of the Sangemini mineral water springs (Terni-Umbria Central Italy) and an estimate of the residence time of the aquifer by coupling Sr and U series isotopic systematics. For this study have been analyzed four water sample for the isotope ratio of 87Sr/86Sr, and eleven samples, shallow waters and groundwaters, for U and Ra, furthermore were determined the values of isotopic ratio for sample of typical rocks of the area. The results of this study allow to identify: a recharge area in a restricted sector of the Meso-Cenozoic carbonates a longer and more effective water/rock interaction in the Quaternary series. U and Ra recoil models allow to estimate a groundwater residence time of about 350 years and a total water volume whose value (64*106 m3) agrees with the limited extension of the aquifer.
The extension of the aquifer was constrained by comparing Sr isotopic composition of waters and local geological formations. Groundwaters seem mainly to circulate in clayey sandy Quaternary series characterized by low redox conditions
\u3csup\u3e230\u3c/sup\u3eTh dating of the speleothems from the Grotta del Fiume-Grotta Grande del Vento karst system in Frasassi (Ancona, Italy) and Paleoenvironmental implications
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
Radium in groundwater hosted in porous aquifers: estimation of retardation factor and recoil rate constant by using NAPLs
A new method for estimating retardation factor and recoil constant of radium isotopes in groundwater hosted in porous aquifers is described. The method is based on the evidence that alpha-recoiled radium ions, supplied by thorium parent atoms which occur in phases immersed in NAPL (Non-Aqueous Phase Liquids), are not adsorbed on solid phases. Experimental evidence is given that manganese dioxide, zeolite 4A, natural clay, monazite and weathered volcanic rock, all phases normally adsorbing radium from aqueous solutions, when immersed in NAPL adsorb negligible amounts of radium. This allows using experimental data on rock samples, representative of porous aquifers, for estimating Ra retardation factor and its alpha recoil constant in groundwater, without using Rn data as a comparison term. Unlike estimation of retardation factor between the "NAPL method" and the method based on comparison with radon depends on the different process of entry from aquifer rock into groundwater for radon and radium. Precise estimates of retardation factor and recoil constants of radium allow to apply equations ruling the temporal evolution of radium isotopes in groundwater and to determine its age. Implications, useful for measuring the contamination age of soils by NAPL fluids, are described as well
Mapping the geogenic radon potential and radon risk by using Empirical Bayesian Kriging regression: A case study from a volcanic area of central Italy
A detailed geochemical study on radon related to local geology was carried out in the municipality of Celleno, a little settlement located in the eastern border of the Quaternary Vulsini volcanic district (central Italy). This study included soil-gas and terrestrial gamma dose rate survey, laboratory analyses of natural radionuclides (²³⁸U, ²²⁶Ra, ²³²Th, ⁴⁰K) activity in rocks and soil samples, and indoor radon measurements carried out in selected private and public dwellings. Soil-gas radon and carbon dioxide concentrations range from 6 to 253 kBq/m³ and from 0.3 to11% v/v, respectively. Samples collected from outcropping volcanic and sedimentary rocks highlight: significant concentrations of ²³⁸U, ²²⁶Ra and ⁴⁰K for lavas (151, 150 and 1587 Bq/kg, respectively), low concentrations for tuffs (126, 123 and 987 Bq/kg, respectively), and relatively low for sedimentary rocks (108, 109 and 662 Bq/kg, respectively). Terrestrial gamma dose rate values range between 0.130 and 0.417 μSv/h, being in good accordance with the different bedrock types. Indoor radon activity ranges from 162 to 1044 Bq/m³; the calculated values of the annual effective dose varied from 4.08 and 26.31 mSv/y. Empirical Bayesian Kriging Regression (EBKR) was used to develop the Geogenic Radon Potential (GRP) map. EBKR provided accurate predictions of data on a local scale developing a spatial regression model in which soil-gas radon concentrations were considered as the response variable; several proxy variables, derived from geological, topographic and geochemical data, were used as predictors. Risk prediction map for indoor radon was tentatively produced using the Gaussian Geostatistical Simulation and a soil-indoor transfer factor was defined for a 'standard’ dwelling (i.e., a dwelling with well-defined construction properties). This approach could be successfully used in the case of homogeneous building characteristics and territory with uniform geological characteristics.Published449-4646A. Geochimica per l'ambiente e geologia medicaJCR Journa