Hancox, G.T.; Bishop, D.G.; McKellar, I.C.; Suggate, R.P.; Northey, R.D. 1980 East Abbotsford landslide: presentation and assessment of engineering geological data and factors related to the cause of the slide. Lower Hutt: New Zealand Geological Survey. New Zealand Geological Survey report EG 332. 232 p.
Abstract: In this report the various factors which possibly contributed to the cause of the East Abbotsford landslides are discusses. The results of site investigations, presented in a previous report (EG328) are also examined and summarised. An appraisal of existing publications and reports on the geology and slope stability of the Green Island - Abbotsford area is also included, with an assessment of the significance of these documents in relation to slope instability and motorway construction. The form and nature of the East Abbotsford landslide is discussed and compared with other major slides in the area. Soil sampling and testing procedures are described, and the results of laboratory tests are presented and discussed in relation to the nature and position of the failure surface, and the possible mechanisms involved in the failure. The emphasis in this report has been to present and assess the available engineering geological data and to identify the factors that could have contributed to instability at Abbotsford, and to evaluate the relative importance of some of these. No attempt has been made to mathematically analyse the stability of the slide area, or to draw conclusions on the most likely cause or causes of the slide. These aspects will be the subject of a subsequent report (NZGS report EG 341).