Brown, I.R. 1974 Engineering geology of tunnel alignments, Auckland rapid transit project. Lower Hutt: New Zealand Geological Survey. New Zealand Geological Survey report EG 197 134 p.
Abstract: This report discusses the engineering geology of the tunnel alignment recommended by the Rapid Transit Steering Committee and that favoured by the Auckland Rapid Transit (ART) Project Directorate. Existing site investigation information was used to predict ground conditions and define areas where further investigations were required. A drilling and testing programme was undertaken along the ART alignment; conditions along the Steering Committee alignment were inferred from existing data. Both tunnel alignments are mainly in low strength Waitemata Group sandstones and siltstones. Tunnelling conditions in these rocks are expected to be uniform except for local areas that are weathered or fractured. The ART alignment has areas of mixed face tunnelling with Waitemata Group and basalts at Newmarket, and Waitemata Group and Pleistocene sediments at Eden Crescent. A landslide intersected by the alignment at Eden Crescent requires further investigation. (auth)