| Summary: | In the Inangahua and Fletcher Creek areas, North Westland, Greenland Group greywackes and argillites, into which the Tuhua Group granitic rocks have intruded, are unconformably overlain by lower Tertiary to lower Pleistocene transgressive and regressive sediments. Several reference sections in the Tertiary strata have been measured, of which the thickest totals over 1000 m, and is subdivided into the Brunner Formation (coal measures): Island Formation; sandstone and algal limestone and the Kaiata Formation, mudstone, interpretted as a transgressive sequence. The Cobden formation, unconformably lapping onto the Kaiata Formation is delimited at its base by a breccia, deposited during Whaingaroan basin warping and basement faulting, and at its top by a glauconitic phosphatic richly fossiliferous horizon. The regressive sequence is represented by the Inangahua Formation of graded bedded foraminiferal limestones, sandstones and silts conformably overlain by coal measures in Fletcher Creek. Overlying the coal measures is a thin sequence of fossiliferous marine strata of possibly Waitotaram age, overlain by Old Man Gravels deposited at the beginning of the Kaikoura Orogeny. Calcareous Algae and a Teredenit are described in detail.
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