Waghorn, D.B.; Morgans, H.E.G. 1997 Calcareous nannofossil and foraminiferal biostratigraphy of the Oligocene to Early Miocene interval 3048-3505 m Mangahewa-1 well, onshore Taranaki. Lower Hutt: Institute of Geological & Nuclear Sciences. Institute of Geological & Nuclear Sciences science report 97/11 11, 5 p.
Abstract: A combination of re-interpreted foraminiferal data and a detailed calcareous nannofossil biostratigraphic investigation of the interval 3048 -3505 metres has established the age relationship and New Zealand Stage correlation of the lower part of the Early Miocene to Oligocene marine interval in the Mangahewa-1 well. The interval ranges in age from Waitakian at the top to early Whaingaroan at the base. Unconformities or condensed sections between the early Whaingaroan Matapo Sandstone Member and the late Whaingaroan-Duntroonian Otaraoa Formation and within the Taimana Formation can be recognised. Benthonic foraminifera indicate that deposition of the most interval occurred at mid to upper bathyal depths. (auths)