Review of mass movements with particular reference to Pipers Valley landslide

Abstract

Landslides and mass movements are serious natural phenomena, resulting from the interaction of several geological and environmental factors. For this dissertation, emphasis is placed on landslide classification, hazard assessment, monitoring, and slope instability, where examples have been drawn from New Zealand and overseas. Case studies illustrate the environmental effects of mass movement, as well as some current engineering geological practices with regard to slope instability and hazard assessment. A study programme was undertaken for the assessment of Pipers Valley landslide, Duvauchelle Bay, Banks Peninsula, associating field observations and measurements to determine the mechanism and mode of failure. Geomorphological mapping (with the aid of aerial photographs and field work) and ground displacement measurements were used to investigate the nature of the landslide. The combination of these various techniques provides a method of assessing ground conditions, and identified a possible hazard to a neighbouring farm property situated in the lower part of a gully. Observations from the preliminary landslide investigations have been correlated in order to propose interpretative cross sections. On the basis of the limited available data, assumptions have been made, and various measures for monitoring and stabilising slide movement are suggested.