Modelling of slope stability is a common practice in Plaxis. Modelling of a volcanic edifice of 16 km wide and 2 km high however, required some pioneering in the familiar finite element package. For geological processes such as magma intrusion and water expansion, Plaxis offers no ready made features. Nevertheless this article will show that with creative use of the program one can accomplish more than might be expected on first sight. The island of San Miguel de la Palma is the most north-western island of the Canary Islands archipelago, situated about 400 km from the coast of central Morocco. The South-western part of the island, which is formed by the Cumbre Vieja volcano has been considered to be more or less unstable by various authors (Ancochea et all, 1994; Carracedo et al, 1999; Day et al, 1999). (Figure 1) Ward and Day (2001) even forecast that an effective collapse of the Island may cause a tsunami in the Altantic ocean. 

This research emcompassed quantifying the likelyness that the supposed La Palma
landslide will actually take place. The (boundary) conditions under which the West flank of the Cumbre Vieja volcano could start sliding have been investigated. Moreover the time lapse from the present day to the day such mass movement would occur was assessed. The purpose of this article is to inform the reader about the specific problems encountered during the modelling of a volcano and the applied solutions. At the same time the results of the research objectives will be discussed briefly.