Jacka, D.; Salt, G. 1982 Investigation of plastic clayey silt near Tarras for core material at Queensberry dam. Lower Hutt: New Zealand Geological Survey. New Zealand Geological Survey report EG 368 38 p.
Abstract:A deposit of heavily over-consolidated Tertiary sediments has been identified adjacent to the Tarras golf course, about 7 km from Queensberry (Maori Point) dam site. The sediments, (which may be classed as soft rocks) vary from silty gravels to clays but with a moderate amount of selective excavation it would apparently be feasible to obtain a plastic, impermeable clayey silt available for dam core material (auth)