Resumen de Fábricas constrictivas de ejes-c de cuarzo en arcosas deformadas por disolución por presión
Francisco José Fernández Rodríguez, D. Brown, Joaquina Álvarez Marrón, Andrés Pérez Estaún, Rosa Ana Menéndez Duarte
Arkosic sandstone interlayered within calcite mylonites at the base o f the southern Urals accretionary prism preserves their original sedimentary microstructure and presents only a weak shape and crystallographic preferred orientation (SPO and CPO, respectively). SPOs of XZ-sections show fabrics mainly formed by pressure solution, where quartz and feldspar grains have a characteristic bimodal shape and the mean axial ratio of the finite strain is c. 2. The unusual pattern described by the quartz c-axes fabrics formed during the acquisition o f their SPOs is characterised by girdles normal to Y At the light o f our results, and accordingly with the deformation conditions o f the calcite mylonites, the quartz c-axis preferred orientation may be formed by pressure solution under constrictional strain, and not as usually occurs by intracrystalline plasticity.
