An extended kinematic inventory, magnitude-frequency curves, and damage assessment of rock slope failures in the central Spanish Pyrenees

Guerrero, J. (Universidad de Zaragoza) ; Guerra, M. (Universidad de Zaragoza) ; Desir, G. (Universidad de Zaragoza) ; Serreta, A. (Universidad de Zaragoza) ; Yannick, T. ; Lucha, P.

Resumen: A new inventory of rock slope failures (RSFs) compiled in the central Spanish Pyrenees within the framework of the SPIRAL Project has identified 1232 RSFs, yielding a relatively low spatial density of 0.11 events per km2. These RSFs exhibit very slow to extremely slow average displacement rates, ranging from 5 mm to 75 mm per year. Rock slides and earthflows are the most prevalent failure types, accounting for over 93% of the total, whereas rock slope deformations (RSDs), composite failures, and rock avalanches are comparatively rare. This predominance of rock slides and earthflows results in a shallower magnitude–frequency distribution relative to other mountainous regions. Lithology, glacial debuttressing, and slope angle are identified as the most influential conditioning factors. Most RSFs occur on slopes between 20° and 30°, especially in deglaciated settings and in bedrock composed of fine-grained, low-strength lithologies, such as turbidites, slates, marls, and evaporitic sequences, where weathering plays a critical role in promoting slope instability. Unfortunately, these relatively moderate slopes, which often correspond to relict landslide deposits, provided favourable conditions for the establishment of at least 25 human settlements in the past. These communities are now under threat and will require multimillion-euro investments to stabilize active movements. Furthermore, 41 RSFs intersect communication and irrigation networks, 138 affect ski resort infrastructures, 94 compromise paved roads, and 29 pose risks to dam safety. The estimated direct costs associated with active RSFs already exceed €152 million, and additional substantial mitigation efforts are anticipated in the near future.

Idioma: Inglés

DOI: 10.1016/j.geomorph.2026.110172

Año: 2026

Publicado en: GEOMORPHOLOGY 498 (2026), 110172 [16 pp.]
ISSN: 0169-555X

Financiación: info:eu-repo/grantAgreement/ES/DGA/E02-23R

Tipo y forma: Article (Published version)

Área (Departamento): Área Expresión Gráfica en Ing. (Dpto. Ingeniería Diseño Fabri.)
Área (Departamento): Área Geodinámica Externa (Dpto. Ciencias de la Tierra)