Forecasting the occurrence of large, catastrophic
slope failures remains very problematic. It is clear that in order advance this field a greater understanding is needed of the
processes through which failure occurs. In particular, there is
a need to comprehend the processes through which a rupture
develops and propagates through the slope, and the nature of
the inter-relationship between the stress and strain states of
the landslide mass. To this end, a detailed analysis has been
undertaken of the movement records for the Selborme Cutting slope failure, in which failure was deliberately triggered
through pore pressure elevation. The data demonstrate that it
is possible to determine the processes occurring in the basal
region of the landslide, and thus controlling the movement of
the mass, from the surface movement patterns. In particular,
it is clear that the process of rupture development and propagation has a unique signature, allowing the development of
the rupture to be traced from detailed surface monitoring. For
landslides undergoing first time failure through rupture propagation, this allows the prediction of the time of failure as
per the “Saito” approach. It is shown that for such predictions to be reliable, data from a number of points across the
landslide mass are needed. Interestingly, due to the complex
stress regime in that region, data from the crown may not be
appropriate for failure prediction