Details of VECTOR-TRANSMED-07 IV leg. Vertical profiles of 210Pb, 137cs and 226Ra in sediment cores.
BackDataset identification
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Title of dataset | VECTOR-TRANSMED-07 IV leg. Vertical profiles of 210Pb, 137cs and 226Ra in sediment cores. |
Narrative summary of dataset | This dataset was acquired in the framwork of Project V.E.C.T.O.R. (VulnErability of the Italian coastal area and marine Ecosystems to Climatic changes and Their rOle in the Mediterranean caRbon cycles).The project studies the most significant impacts of climate change on the Mediterranean marine environment and the role of this basin on the planetary CO2 cycle. |
Summary of processing methodology | All sediment cores were sampled using a cylindrical (ID, 32 cm; height 52 cm) box corer equipped with top valve which ensures the recovery of surface sediment with minimal disturbance. Subsamples were collected by PVC tubes (10 cm diameter) onboard and sliced with a precision extruder at 0.5 cm intervals in the top 2 cm, and at 1 cm resolution thereafter down to the core bottom. Once in the laboratory, sediment samples were weighed wet, then dried at 50 °C to constant weight, in order to determine wet and dry bulk density. 210Pb, 226Ra and 137Cs were measured on 10 g aliquots of dried sediment samples in a standard geometry by gamma spectrometry. Samples were sealed and sample counting took place 20 days after, a time interval sufficient to re-establish radioactive equilibrium between 226Ra and 222Rn. Three ORTEC HPGe gamma detectors were used to perform analyses; the detectors have an efficiency of 30–60% and a nominal resolution from 1.9 to 2.5 keV at the 1.33 MeV 60Co gamma emission. Sediment samples were counted for 2–3×105 s and 210Pb activities were corrected for self-adsorption effects for the detection of low-energy gamma rays, such as the 46.5 keV ray of 210Pb (Cutshall et al., 1983). Excess 210Pb (210Pbxs) activity was determined as the difference between total 210Pb and supported 210Pb (in equilibrium with the parent radionuclide 226Ra). Dataset variables decoding: PORO: Porosity MSDP: Mass depth Bot. Depth [m]: length of sediment core Depth [m]: sediment core layer PB0S: 210Pb excess activity (sediment) EPBS: 210Pb excess activity error (sediment) RA6S: 226Ra activity (sediment) ERAS: 226Ra activity error (sediment) |
Supporting documentation | Barsanti, Mattia et al. 2011, "Sediment reworking rates in deep sediments of the Mediterranean Sea", Science of the Total Environment, (409):2959-2970, doi:10.1016/j.scitotenv.2011.04.025 |
Project/programme | VECTOR-Vulnerability of coasts and marine ecosystems to the climatic changes and their role on Mediterranean C cycle |
Start date | 2007-07-02 |
End date | 2007-07-10 |
Frequency of observations | inapplicable |
Responsible organisations
Country | Italy |
Organisation name | ENEA Centro Ricerche Ambiente Marino (La Spezia) |
Role of organisation | Originator of Dataset |
Dataset availability
Original dataset download link | https://cloud.emodnet-ingestion.eu/index.php/s/gfpeDPQKC9zm1TJ |
Date of original dataset publication | 2018-03-09 |
Dataset format | Text or Plaintext |
Public access | No limitations |
License for use | CC BY-SA 4.0 |
Type | Dataset |
DOI | https://doi.org/10.1016/j.scitotenv.2011.04.025 |
Locations
Map | © OpenStreetMap contributors |
Latitude north boundary | 38 |
Longitude east boundary | 29 |
Latitude south boundary | 32 |
Longitude west boundary | 18 |
Coordinate reference system | World Geodetic System 84 |
Sea area | Mediterranean Sea, Eastern Basin |
Data types, collection and processing
Observation type | Isotopes |
Parameter | Geological sample radioactivity |
Instrument type | gamma-ray spectrometers |
Instrument name | GEOTEK Multi-Sensor Core Logger XYZ {MSCL-XYZ} core analyser |
Platform type | research vessel |
Platform name | Urania |
Data quality processing information | The ORTEC HPGe gamma detectors have an efficiency 30–60% and a resolution from 1.9 to 2.5 keV at the 1.33 MeV 60Co gamma emission. Each detector is accurately calibrated as follows: for 210Pb, the CANMET (CANada centre for Mineral and Energy Technology) reference standard DL1a is used; calibration for 137Cs and 7Be is performed using the multi-elemental Amersham reference standard solution QCY48. The accuracy of the results is verified through quality controls routinely realized by analyzing standard reference materials of the International Atomic Energy Agency (IAEA-300, IAEA-315 and IAEA-385). Detector blanks are monthly determined from measurements performed on empty sample containers over a few days. Sediment samples were counted for 2-3 days and the gamma-ray spectra were analysed for the selected radionuclides at the following photopeaks: 210Pb at 46.5 keV, 226Ra (as an estimate of supported 210Pb), via 214Pb at 352 keV and 214Bi peaks at 609 keV, 7Be at 477.7 keV, 137Cs at 662 keV. 210Pb activities were corrected for self-absorption effects for the detection of low-energy gamma rays, accordingly to Cutshall et al. (1983). Excess 210Pb (210Pbxs) activity is the difference between total 210Pb and supported 210Pb (in equilibrium with the parent radionuclide 226Ra). |
Process information
Submitting organisation | ENEA Centro Ricerche Ambiente Marino (La Spezia) |
Submission identifier (UUID) | aa3559be-8e4c-46a3-842a-0382ab0284dc |
Date of dataset creation | 2009-01-01 |
Date of dataset revision | 2009-01-01 |
Date of metadata creation | 2017-11-22 |
Date of metadata latest revision | 2018-02-27 |
Date of publishing | 2018-02-26 |
Processing data centre | ENEA Centro Ricerche Ambiente Marino (La Spezia) |
Summary record-ID | 74 |