Abstract A NNE-striking belt of Late Cretaceous-Early Tertiary sediments in the area between Whareama and Ngahape consists of a sequence, from base to top, of: sandstone, conglomerate, and minor siltstone (Glenburn Formation); thin-bedded sandstone and mudstone (Te Mai Formation); siltstone (Whangai Formation); black siltstone (Waipawa Formation); and glauconitic sandstone (Huatokitoki Formation). The belt is faulted against indurated, strongly deformed Early Cretaceous sandstone and siltstone (Pahaoa Group) in the west, and overlain unconformably by Late Tertiary (Miocene) sediments in the east. Shallow intrusions of dolorite and basalt, and submarine basalt flows, comprising the Ngahape Volcanic Complex (new), occur mostly in the upper part of the sequence. Volcanic activity was probably restricted to late Maastrichtian-early Paleocene (Haumurian-Teurian) time. The Late Cretaceous-Early Tertiary formations are considered to have been deposited in inner shelf or marine delta (Glenburn), tidal strait (Te Mai), and shallow restricted basin (Whangai and Waipawa) environments. Major faults, including the new Motuwaireka Fault, in the area mostly trend NNE. Significant discoveries with respect to faults are: repeated movement (late Cretaceous, Pliocene, and Recent?) on Adams Fault, forming the western boundary of the belt; a reverse component of movement on the low-angle (20–40°) west-dipping Pukeroro Fault; and strike-slip (dextral) movement on the ENE-trending Kaumingi Fault. Faulting and folding took place during deposition of Late Cretaceous-Early Tertiary sediments, resulting in penecontemporaneous erosion and slumping. Major tectonic upheaval occurred in post-late Paleocene time, probably in the early Eocene.