Evolución geomorfológica en la transversal del río Besaya (Cordillera Cantábrica, España)
- J.F. Mediato 1
- F. Moreno 1
- P.P. Hernaiz Huerta 1
- C. Peropadre 1
- F.J. Solé 1
- F. Sarrionandía 1
- 1 INYPSA Informes y Proyectos S. A.
ISSN: 1576-5172
Year of publication: 2012
Issue Title: VIII Congreso Geológico de España, Oviedo, 17-19 de julio, 2012.
Issue: 13
Pages: 714-717
Type: Article
More publications in: Geotemas (Madrid)
Abstract
Landforms and related sediments located in the upper reaches of the Besaya river and its divide with the Ebro basin (Reinosa area) allow to understand the deeply incised Cantabrian drainage network evolution in comparison to the nascent fluvial incision in the Ebro headwaters.The most relevant feature of this evolution is the development of a palaeorelief corresponding to palaeovalleys bottoms which have been preserved in the lowest points of the divides between both rivers and as shoulders in the Besaya valley. Occasionally, this palaeorelief is covered by mixed (fluvial + gravitational) deposits of an inferred Mio-Pliocene age. The incision of the Besaya drainage network progressed in the referred palaeovalleys eroding its Mio-Pliocene sedimentary cover and reworking it in multi-episode mega fluxes (debris flows of considerable thickness) and alluvial fans, which in turn are being incised by present day drainage. Active tectonism in the area is revealed by the activity of a family of N-S striking normal faults, which cut at least one of these mega fluxes and trigger large landsides as well as hydrothermal sources.