RT Journal Article
T1 Regional-scale high-plasticity clay-bearing formation as controlling factor on landslides in Southeast Spain
A1 Azañón, J.M.
A1 Azor Pérez, Antonio
A1 Yesares, Jesús
A1 Tsige Beyene, Meaza
A1 Mateos Ruíz, Rosa María
A1 Nieto, Fernando
A1 Delgado, Jorge
A1 López Chicano, Manuel
A1 Martín, Wenceslao
A1 Rodríguez Fernández, José
AB Complex landslides in clay-bearing sediments are investigated in two moderate-relief regions of Southeast Spain. Both regions, more than 100 km apart show landslides affecting the same Flysch formation, which outcrops widely in the central and western Betic Cordillera along the contact between the External (South Iberian Domain) and Internal (Alborán Domain) zones. Intense rainfall episodes can be considered as the main triggering factor for slope failures in these two areas. We have chosen two landslides (Diezma and Riogordo landslides), one from each area of study, to investigate their morphological and geotechnical features in order to establish the relative importance of the different controlling factors. From a kinematic point of view, the two features studied in detail can be referred as to rotational failures, evolving downhill to slow earthflows. The movement was concentrated on several surfaces developed on a clay-rich layer mostly constituted by smectite. This clay mineral is of critical relevance to the mechanical behaviour of soils and Flysch-like formations, being very consistent at dry conditions, but rapidly losing its strength at wet conditions. Thus, softened smectite-rich clay layers with high water contents can approach the properties of a lubricant, which, in turn, can be critical for slope stability. In addition to their high plasticity, these clays have a high swelling potential, which can induce significant vertical overpressure, thus reducing even more the strength properties of the Flysch formation. In Southeast Spain, a region with a Mediterranean rainfall regime, slope stability can be seriously influenced by the presence of these smectite-rich clay layers in a formation of regional extent, as is the case of the Flysch formation. Therefore, this lithologically-controlled factor should be taken into account when evaluating landslide hazard in the Betic Cordillera.
PB Elsevier Science B.V., Amsterdam
SN 0169-555X
YR 2010
FD 2010
LK https://hdl.handle.net/20.500.14352/43423
UL https://hdl.handle.net/20.500.14352/43423
LA eng
NO Consejería de Obras Públicas de la Junta de Andalucía
NO Spanish Ministry of Science and Innovation
NO TOPO-IBERIA CONSOLIDER-INGENIO
DS Docta Complutense
RD 17 abr 2025