Modelos cinemáticos de la deformación varisca en la zona de cizalla de Hiendelaencina (Anticlinorio del Ollo de Sapo, Zona Centroibérica)

Resumo

The kinematic models applied to evaluate the ductile shear zone of Hiendelaencina (second Variscan phase affecting the Ollo de Sapo Anticlinorium, Central Iberian Zone, Iberian Massif) are based on untenable assumptions about the non-simultaneous activity of the distinct acting flow components (simple shear, pure shear, volume change). In this work, the finite strain and plano-linear fabric data from the Hiendelaencina shear zone are tested against recent models considering triclinic flow histories. Two sectors (A to the NW, and B to the SE in the original arrangement of the sub -horizontal to gently NW-dipping shear zone) have been identified according to their contrasted kinematic characteristics. The simple shear component implies top-to-the -SE displacement for both sectors. The pure shear component includes sub -vertical shortening and E-W extrusion for sector A, and sub -vertical lengthening and E-W shortening at sector B. These differences are interpreted as due to heterogeneous flow partitioning within a general restraining bend structure.