publication . Article . 2016

Goethite (U–Th)/He geochronology and precipitation mechanisms during weathering of basalts

Riffel, Silvana B.; Vasconcelos, Paulo M.; Carmo, Isabela O.; Farley, Kenneth A.;
Open Access
  • Published: 23 Dec 2016
  • Publisher: Elsevier
  • Country: United States
Abstract
(U–Th)/He geochronology of 33 goethite grains from in situ ferruginous duricrusts overlying the Paraná flood basalt in the Guarapuava region, Paraná, Brazil, reveals ages ranging from 3.6 ± 0.4 to 0.4 ± 0.1 Ma. Thirty-one grains from detrital fragments of ferruginous duricrust yield ages in the 6.2 ± 0.6 to 0.7 ± 0.1 Ma range. The results show that goethites from detrital blocks are generally older than those from the in situ ferruginous layers and that all the goethites from the Guarapuava sites are relatively young (≤ 6.2 ± 0.6 Ma). Goethites show variable U and Th contents depending on the mode of precipitation. Goethite that forms by progressive ferrugizatio...
Related Organizations
Download from
Caltech Authors
Article . 2016
Powered by OpenAIRE Open Research Graph
Any information missing or wrong?Report an Issue