Paterson, B.R. 1974 A preliminary geological appraisal of the Mangaio Tunnel proposals, Tongariro power development. Lower Hutt: New Zealand Geological Survey. New Zealand Geological Survey report EG 176 9 p.
Abstract: The purpose of this report is to summarise the geology and anticipated tunnelling conditions for the unexcavated section of the Mangaio Tunnel. Most of the information included was discussed during a meeting at Project Office, Turangi on 30 November 1973. (auth)