Late Neogene stratigraphy of the Carrington area, western Wairarapa, North Island, New Zealand

Abstract

Abstract Nearly two kilometres of mostly marine sediment accumulated in western Wairarapa during Late Neogene basement subsidence, Fossil content and lithological trends within the Upper Neogene marine strata record episodes of rise and fall in sea level which are related to the combined effects of basement subsidence, local faulting and tilting and global changes in sea level. The stratigraphy of western Wairarapa is similar to that described for Upper Neogene sediments adjacent to the Aorangi Range in south-east Wairarapa. The oldest Cenozoic sediments exposed in the Carrington area, west of Carterton are a fining-upward sequence of fluvial then marine conglomerate, sandstone, siltstone and deep water, tuffaceous mudstone (Mangaoranga Formation of Neef, 1974), which accumulated during rise in sea level between lOMy BP and 5.5 My BP. Fall in sea level after 5.5 My BP is indicated by a sudden change in lithology to shallow water limestone (Hururua Limestone Formation; new name). The limestone contains wel...