García Cuevas, C.González Casado, J. M.2015-04-132015-04-131997http://hdl.handle.net/10272/10322In the central part of the Cameros basin (NW Iberian Chain) has been analysed the orientation of calcite c-axes and e-twin from the sparitic grains that filled extension veins in this region. The c-axls orientations allow to establish that during the mesozoic extensional episode, when was developed this basin, besides of an extension NE-SW also existed another with a NNW-SSE trend, this last extension direction probably has a regional character. The calcite e-twins show the existence of two different orientations for strain ellipsoids. A first group has orientations that would be compatible with structures associated with the development of the basin inversion and with the NE-SW schistosity. While the other is almost perpendicular to the former and it is compatible with a NW-SE compression not described until the moment. This last deformation episode probably has a regional meaning (Cuadarrama compression? from Capote et al., 1990), and it likely also has a relative importance in the development of structures that show this regionspaAtribución-NoComercial-SinDerivadas 3.0 Españahttp://creativecommons.org/licenses/by-nc-nd/3.0/es/Iberian ChainCameros basinsCalcite veinCalcite e-twinsStrain determinationsjournal articleopen access