(Table 1) Radionuclides and ESR dating of sediment cores PS1535-10 and PS1535-8

• Main Authors: Hoffmann, Dirk L, Woda, Clemens, Strobl, Christopher, Mangini, Augusto
• Format: Dataset
• Language: English
• Published: PANGAEA 2001
• Subjects: Age; dated; dated standard deviation; electron spin resonance (ESR); Age model; optional; stable isotope stratigraphy; ARK-IV/3; Calculated from weight/volume; DEPTH; sediment/rock; Dose rate; standard deviation; Equivalent dose; Fram Strait; GIK21535-10 PS11/430-10; KL; Method comment; Piston corer (BGR type); Polarstern; Potassium; PS11; PS1535-10; Thorium-230; Thorium-232; Uranium-234/Uranium-238 activity ratio; Uranium-238; Water content; wet mass; Arctic; Foraminifera*
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.120604; https://doi.org/10.1594/PANGAEA.120604

ESR-spectra of foraminifera in arctic sediment cores display the [CO2]- -signal (g=2.0006). Research on the thermal behaviour of the [CO2]- -signal shows that both natural and artificial irradiation generates a precursor and a thermal unstable component of the [CO2]- -signal. The precursor can be transfered to the stable radical, and unstable radicals can be removed by heating. The signal-change by heating depends on the irradiation dose. Because of the varying response on thermal treatment, the dose-response curves show systematic differences depending on the applied procedure (single- or multi-aliquot method with or without heating). A model for the description of the [CO2]- -signal-change is presented. The combination of two exponential saturation functions seems to be an adequate analytical description of the dose-response curve of the [CO2]- -signal in foraminifera. Due to the limited thermal stability this signal can be used for dating foraminifera with ages up to about 190 ka.