First fission-track age for the dinosaur-bearing Neuquén Group (Upper Cretaceous), Neuquén basin, Argentina

HUGO CORBELLA; FERNANDO E. NOVAS; SEBASTIÁN APESTEGUÍA; HÉCTOR A. LEANZA

Revista del Museo Argentino de Ciencias Naturales, nueva serie

Museo Argentino de Ciencias Naturales

Lugar: Buenos Aires; Año: 2004 p. 227 - 232

The first radiometric age for the Neuquén Group, based on fission track analysis made on an ashflow tuff at the base of the Huincul Formation is reported in this paper. The radiometric age offers a more precise chronological dating for the time of deposition of the first stages of the Neuquén Group. The tuff, exposed at Cerro Policía hill and other close localities in Río Negro Province (NW Patagonia), has yielded a radiometric age of 88+3.9 My. This value suggest that the Huincul Formation was deposited between an age range from 84.1 to 91.9 My, that is from the base of the Turonian to the top of the Santonian.