Details zur Publikation

Referenztyp Zeitschriften
DOI / URL Link
Titel (primär) 14C dating of Gorleben groundwater
Autor Buckau, G.; Artinger, R.; Geyer, S.; Wolf, M.; Fritz, P.; Kim, J.I.;
Journal / Serie Applied Geochemistry
Erscheinungsjahr 2000
Department HDG;
Band/Volume 15
Sprache englisch;
Abstract Previous attempts to apply 14C for dating of groundwater in the Gorleben aquifer system has given results with conflicting 3H and stable isotope data and hydrological estimates. 14C model ages of 1–10 ka have been found for 3H containing recharge water, up to 31 ka for groundwater with Holocene stable isotope signatures and 6–10 ka for groundwater at 35 m depth. In this paper it is shown, that the reasons are assumption of to high 14C concentration in recharge groundwater and not correcting for the influence of 14C dilution by dissolved inorganic C (DIC) from microbiologically mediated mineralization of organic components in deep sediments. To overcome these difficulties a new approach is applied evaluating the site-specific 14C source term (including the influence of nuclear atmospheric testing), and the already previously used overall dilution of DIC. Closed system conditions are assumed and no isotopic fractionation is considered. For most of the groundwaters, the 14C ages achieved by the present method are in agreement with 3H, stable isotopes and hydrological estimates. It is shown that down to approximately 140 m depth no 14C decay can be detected. Situations are also discussed, either where the 14C method is not applicable (shallow peat-bog like groundwater) or does not yield reliable groundwater ages (brines at <200 m depth).
ID 7053
dauerhafte UFZ-Verlinkung http://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=7053
Buckau, G., Artinger, R., Geyer, S., Wolf, M., Fritz, P., Kim, J.I. (2000):
14C dating of Gorleben groundwater
Appl. Geochem. 15 , 583 - 597