The Geology of the Te Wharau-Flat Point Area, Eastern Wairarapa

Abstract

The stratigraphy and structure of the Te Wharau-Flat Point area, Eastern Wairarapa is described and illustrated by a map. Strata in upward succession are: Taitai greywackes with spilites; Ngaterian to Piripauan gradational group of feldspathic to quartzose sandstones, siltstones and conglomerates; Haumurian and Teurian, brown siltstone with glauconitic sandstone; Teurian and Lower Dannevirke, limestone and greensand; Upper Dannevirke and Bortonian, sandstone and siltstone with bentonitic mudstones. Southland alternating sandstone and siltstone lie unconformable on older strata and show a distinct erosion interval in Clifdenian-Lillburnian times. Pleistocene and Recent deposits consist of marine terrace veneer, aeolian and fluviatile material. Dolerite intrusions, possibly Maestrichtian, cut Clarence and Raukumara strata, have alkaline affinities and appear to be of the same age as teschenite intrusions further north. The strata are much deformed by slumping, major and later folding occurred along north-north-east foldaxes, but most folds are disrupted by faults striking parallel to the fold-axes.