Isaac, M.J.; Brook, F.J.; Hayward, B.W. 1988 The Cretaceous sequence of Whatuwhiwhi, Northland, New Zealand, and its paleogeographic significance. Lower Hutt: New Zealand Geological Survey. Record / New Zealand Geological Survey 26 32 p.
Abstract: At Whatuwhiwhi, Karikari Peninsula, New Zealand, late Early Cretaceous acidic and basic submarine volcanics of the Rangiawhia Volcanics, Houhora Group, are intercalated with Tokerau Formation mass flow breccia, sandstone, thin bedded sandstone and mudstone. A major unconformity separates Houhora Group from the overlying Whatuwhiwhi Formation, which comprises a post- orogenic, upward-fining sequence of four major lithofacies associations, with unsorted breccia near the base, and mudstone at the top. ... It is concluded that Houhora Group rocks constitute a ''suspect terrane'' with respect to the Permian-Jurassic Waipapa basement, that Whatuwhiwhi and Waiari Formations are essentially autochthonous and that at Whatuwhiwhi, neither the Houhora group nor the overlying units are a part of the Northland Allochthon.