Author Retains CopyrightKustanowich, Solomon2011-05-052022-10-262011-05-052022-10-2619641964https://ir.wgtn.ac.nz/handle/123456789/24180A broad north-east trending horst of Upper Cretaceous grey to brown argillites (Whangai facies) occupies the greatest part of the area. It is flanked on both sides by younger sediments. Down-faulted to the east, is a Lower Miocene sequence of alternating, graded-bedded sandstones and mudstones. Down-faulted still further to the east is a small outlier on the coast at Castlepoint, consisting of a Lower Pliocene mudstone, and a Lower Pleistocene limestone. Down-faulted to the west of the Upper Cretaceous belt are complexly faulted sediments ranging from early to middle Tertiary in age. These outcrop in the Middle Tinui Valley. The Eocene - Lower Oligocene sediments consist of fine-grained light-coloured argillites, including bentonites and calcareous siltstones. The Upper Oligocene is represented by a basal conglomerate and graded-bedded sandstones and mudstones, locally overlain non-conformably by basal Miocene reef-limestone and calcareous sandstone. Down-faulted further to the west are middle Miocene massive blue-grey siltstones, passing into graded-bedded sandstones and mudstones in the Upper Tinui Valley. The structural trend is defined by continuous major north-north-east trending faults. Subsidiary west-north-west and north-trending faults are also present. The major fold structures are not as clearly defined.pdfen-NZhttps://www.wgtn.ac.nz/library/about-us/policies-and-strategies/copyright-for-the-researcharchiveGeologyWairapaTextAll rights, except those explicitly waived, are held by the Author