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The development of progressive failure in slopes is a poorly understood process, and relatively few advances in terms of the mechanics of the development of failure have been made since 1967. However, advances in the understanding of the development of fractures in brittle materials provide new insights into landslide mechanics. In addition, the link between the deformation mechanism and movement type allows interpretation of displacement records to determine the mechanisms acting within a slope. This paper utilizes these insights into deformation processes, combined with 'reinflation' stress-path triaxial experiments, to propose a new model for the development of a progressive, first-time failure within a slope. This model is able to explain the development of failure when the factor of safety is greater than unity, the existence of 'Saito' linearity (a linear trend when the reciprocal of velocity prior to failure is plotted against time) during tertiary creep, and the development of failures during periods of apparently increasing normal effective stress. Keywords: landslides, deformation, microcracks, failure, strain.

The movement of rotational and translational landslides occurs as a result of either sliding on discrete shear surfaces or ductile deformation within a shear zone. In this paper we examine the movement histories of a number of landslides that occurred in a variety of materials in a range of settings, and demonstrate that one of two movement styles is evident during accelerating phases for all landslides observed. The first style, which has previously been noted, has a linear form in a plot of 1/v against time (v is velocity). The second style has an asymptotic form in the same plot, trending toward steady-state movement rates. We propose that the linear form occurs in landslides in which crack propagation (i.e., shear surface generation) is the dominant process, whereas the second style occurs where movement is taking place across existing planes of weakness or as a result of ductile deformation processes. This study demonstrates that the evaluation of plots of 1/v against time for landslides is a useful technique for forecasting movement styles and rates, and for interpreting ongoing deformation processes in real time. Keywords: landslides, acceleration, brittle deformation, ductile deformation displacements.

Landslides are a ubiquitous hazard in terrestrial environments with slopes, incurring human fatalities in urban settlements, along transport corridors, or at sites of rural industry. Assessment of landslide risk requires high quality landslide databases. Recently, global landslide databases have shown the extent to which landslides impact on society and identified areas most at risk. Previous global analysis has focused on rainfall-triggered landslides over short ~ 5 year observation periods. This paper presents spatio-temporal analysis of a global dataset of fatal non-seismic landslides, covering the period from January 2004 to December 2016. The data show that in total ~ 56 000 people were killed in 4862 distinct landslide events. The spatial distribution of landslides is heterogeneous, with Asia representing the dominant geographical area. There are high levels of inter-annual variation in the occurrence of landslides. Although more active years coincide with recognised patterns of regional rainfall driven by climate anomalies, climate modes (such as ENSO) cannot yet be related to landsliding, requiring a 30+ year landslide dataset. Our analysis demonstrates landslide occurrence triggered by human activity is increasing, in particular in relation to construction, illegal mining and hill-cutting. This supports notions that human disturbance may be more detrimental to future landslide incidence than climate. [ABSTRACT FROM AUTHOR]