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Accueil du site → Doctorat → Royaume-Uni → 1997 → Modelling mass movement risk under semi-arid mountainous conditions : the Alpujarride complex, Spain.

University of London (1997)

Modelling mass movement risk under semi-arid mountainous conditions : the Alpujarride complex, Spain.

Alcantara-Ayala, Irasema

Titre : Modelling mass movement risk under semi-arid mountainous conditions : the Alpujarride complex, Spain.

Auteur : Alcantara-Ayala, Irasema.

Université de soutenance : University of London

Grade : Doctor of Philosophy (Ph.D.) : 1997

Résumé
Interactions between geology, topography and climate determine complex processes, such as mass movement. In semi-arid environments the magnitude and frequency of different meteorological events have a major control on short term, seasonal and long term groundwater conditions, inasmuch as seepage is related to topography and topography is related to river under-cutting, depending on the geological conditions.In the Alpujarras, Southern Spain, mass failure processes take place over a large area due to the interrelationships among these elements. Phyllites outcrop over a large part of the region and cause slope stability problems not only in Southern Spain, but within the Mediterranean. A conjugate faulting system existent on these rocks is reflected in a set of preferential planes of weakness, which in addition to the material properties enhance mass failure. The analysis of the interrelationships of these structural, morphological, hydrological and climatic factors by means of modelling and in order to predict mass movement in space and time under semi-arid environmental conditions is the aim of this research.Three models have been coupled to test this kind of interaction. First of all, a hydrological budget model for percolation to groundwater has been used, followed by a finite element model for groundwater flows, and finally, the results are incorporated into a slope stability model. The modelling results suggest that failure is, in general, strongly related to morphology and erosional processes, rather than climate, except in the case of the shallow failures controlled by events of high magnitude and low frequency.

Mots clés : Slope stability ; Groundwater ; River under-cutting Geology Mineralogy Sedimentology Hydrology Meteorology Climatology Geology Hydrology Meteorology

Annonce : EThOS (UK)

Proquest Dissertations & Theses

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