RT Journal Article
T1 El metamorfismo en la Cuenca de los Cameros. Geocronología e implicaciones tectónicas
A1 Casquet Martín, César
A1 Galindo, Carmen
A1 González Casado, J. M.
A1 Alonso, Ángela
A1 Mas, Ramón
A1 Rodas, M.
A1 García, E.
A1 Barrenechea, J. F.
AB A case of hydrothermal metamorphism is described from the Cameros Basin along the rio Cidacos transect. The highest grade is reached at the base of the Urbión Group, a fluvial sequence Upper Jurassic to Lower Cretaceous in age (Wea/d facies). Physical conditions at the thermal peak are estimated at ab. I Kb (PL) and 326± 130 C (i.e. very Iow grade metamorphism). Fluids were largely water brines with minor amounts of gases, C02 and CH4. f02 and fS2 were close to the graphite and Po-Py buffers respectively. This metamorphism is spatially associated with a deformation band (5-6 km. in width) with schistosity in the pelitic beds and prominent tensional, quartz infilled veins in the more samitic ones. 1<-Ar dating on authigenic illites has given ages from 708 to 86 M.a., i.e. Middle Cretaceous, and thus younger than the basin filling (Urbión GroupÆnciso F.+Olivan F.). Metamorphism migth be related with the circulation of hot migratory fluids (i.e. tectonic brines), along the deformation band. The tectonic significance of this deformation band is still uncertain
PB Sociedad Geológica de España
YR 1991
FD 1991
LK http://hdl.handle.net/10272/17982
UL http://hdl.handle.net/10272/17982
LA spa
DS Repositorio Institucional de la Universidad de Huelva
RD 31 may 2026