1,721,091 research outputs found
USING C-14 BOMB PULSE FOR THE STUDY OF CARBON EXCHANGE FLUXES IN TERRESTRIAL ECOSYSTEMS. Oral communication at the ESF-IAAMS workshop:”Applications of cosmogenic isotope analysis in earth and environmental sciences”, Vienna.
No full textEstimating soil organic matter dynamics by means of 14C models: Theoretica l and experiment al evidences. Invited introductory lecture at COST Action ES806 Stable Isotopes in Biosphere- Atmosphere -Earth System Research (SIBAE): WG2 Workshop: “Applicati on of stable isotopes for studying and modelling soil respiratio n and soil organic matter cycling”.
No full textCOST Action ES806 Stable Isotopes in Biosphere- Atmosphere -Earth System Research (SIBAE): WG2 Workshop: “Applicati on of stable isotopes for studying and modelling soil respiratio n and soil organic matter cycling”
Characterization of a new protocol for mortar dating: 13C and 14C evidences
Full text linkThis paper reviews the present knowledge about the analysis of mortars in the framework of artworks absolute chronology determination with the aim to formulate a new methodology capable of systematically and accurately estimating the age of these constructive and/or art materials. The core of the proposed methodology is represented by a physical procedure (ultrasonication) selecting only carbonaceous materials represented by carbonates formed after the absorption of
atmospheric CO2 (carbonatation) by mortars (binder) during their setting. With the aim to evaluate the procedure efficiency in the isolation of binder signal from the most important source of carbonates, the proposed procedure was tested on a series of laboratory mortars produced, in a simplified version, in the laboratory environment. Mortar production was characterized by means of a series of measurements allowing to draw important indications about the applied procedure. The radiocarbon value of isolated binder carbonates was compared with the CO2 signal sampled
form laboratory air during mortar setting. The observed results confirmed preliminarily the good protocol accuracy for radiocarbon dating suggesting its capability for the application to real study cases
Using elevation gradients to study climate controls on soil carbon dynamics. Invited talk at the European Geosciences Union General Assembly 2009
No full textDating mortars: Three medieval Spanish architectures
No full textOne of the major issues in building archaeology is finding the age of elements and structures discovered. Mortars represent a class of material basically constituted by a mixture of different phases (i.e. binder, aggregates, water) and are widely used for constructive uses and artworks. Current scientific literature regarding the possibility of accurate radiocarbon dating for mortars reports different and still contradictory results. In this study, a new protocol for radiocarbon dating of mortar developed at the Centre for Isotopic Research on Cultural and Environmental heritage (CIRCE) is used to perform 14C measurements on archaeological mortars coming from three medieval architectures of northern Spain (two churches and the walls of a castle). Results observed will be discussed and compared with independent age estimations (i.e. radiocarbon dating performed on organic materials found in the same study site, archaeological analyses) in order to frame experimental observations in the actual site knowledge by means of a multidisciplinary approach
The beginning of the Iron Age at Arslantepe: a 14C perspective
Full text linkThe Iron Age chronology at Arslantepe is the result of the interpretation of Luwian hieroglyphic inscriptions and archaeological data coming from the site and its surrounding region. A new round of investigations of the Iron Age levels has been conducted at the site over the last 10 years. Preliminary results allowed the combination of the archaeological sequence with the historical events that extended from the collapse of the Late Bronze Age empires to the formation and development of the new Iron Age kingdoms. The integration into this picture of a new set of radiocarbon (14C) dates is aimed at establishing a more solid local chronology. High precision 14C dating by accelerator mass spectrometry (AMS) and its correlation with archaeobotanical analysis and stratigraphic data are presented here with the purpose of improving our knowledge of the site’s history and to build a reliable absolute chronology of the Iron Age. The results show that the earliest level of the sequence dates to ca. the mid-13th century BC, implying that the site started developing a new set of relationships with the Levant already before the breakdown of the Hittite empire, entailing important historical implications for the Syro-Anatolian region at the end of the 2nd millennium BC
Inter-comparison of methods for quantifying above-ground leaf litter decomposition rates
No full textForensic applications of 14C at CIRCE.Contributed Talk alla conferenza europea sull'applicazione degli acceleratori alla ricerca e la tecnologia (ECAART). Atene 13-19 Settembre 2010.
No full textRadiocarbon dating versus volcanic event stratigraphy: Age modelling of Quaternary marine sequences in the coastal region of the Eastern Tyrrhenian Sea
No full textWe present the results of an integrated stratigraphic study conducted on eight marine sediment cores collected in the Naples and Salerno Bays, Eastern Tyrrhenian Sea. The aim of the study is the understanding of the timing and the impacts on the sedimentary environment of explosive volcanic events that occurred over the coastal zone of the Campania region during the latest Quaternary. Accurate dating and correlation have been essential for the construction of reliable models of the sediment architecture and influx rates in this area, as well as for establishing the links between changes in sedimentation and palaeoenvironmental events. While in case of deep marine sequences distal ash layers usually offer a significant potential for accurate geochronology, in the case of shallow marine sequences (continental shelf to upper slope) radiocarbon dating revealed to be essential in order to refine correlation among clusters of marine tephra layers with the equivalent proximal pyroclastic deposit onland, particularly where depositional rates are high and the chemistry and age of tephra layers display little variability. The integrated use of AMS 14C dating on marine materials and the tephrostratigraphic approach based on reconstructions of historical volcanic events is fundamental in order to minimize the uncertainties that affect chronologic constraints derived from radiocarbon-based age models. © 2009 Elsevier B.V. All rights reserved
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