RT Journal Article T1 Estructura del sector norte de la Cuenca de Almazán (Cordillera Ibérica) T1 Structure of the northern border of the Almazan basin (Iberian Chain) A1 Maestro González, Adolfo A1 Cortés Gracia, A. L. A1 Casas Sainz, Antonio AB The Tertiary compressional structure of the northern sector of the Almazan basin is defined by several E-W to NW-SE trending folds. These folds extend from the northern and eastern basin borders to the central part. Ceometrical reconstructions obtained from the study of seismic reflection profiles and outcrop observations indicate that the folds in the Paleogene beds can be followed to the Mesozoic strata below them and to the Palaeozoic basement. Their wavelength varies between 7 and 5 l