Hautotara, Te Muna and Ahiaruhe Formations, middle to late Pleistocene, Wairarapa, New Zealand.

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Abstract
The Hautotara, Te Muna and Ahiaruhe Formations are formally described for the first time. The Hautotara Formation contains the littoral marine and estuarine deposits of the Huangarua Cyclothem together with underlying freshwater deposits which have been added for mapping convenience, and is considered to be late Marahauan (c. 1.2 to 1.05 Myr) in age. The Te Muna Formation is a conformable sequence, 366 m thick, containing fifteen members. Alluvial gravels alternate with freshwater blue-grey silt and sand with lignite layers, tree roots in growth position and occasional paleosols. The Te Muna Formation also contains loess at one horizon, and localised rhyolitic tephra beds. The tephras and preliminary paleomagnetism indicate a Castlecliffian age (c. 1.0 to 0.4 Myr). The Ahiaruhe Formation consists of alluvial gravel varying from a few metres to more than 80 m in thickness, interbedded with water-laid, partly loessic silts locally containing Mount Curl Tephra (c. 0.23 ± 0.04 Myr; equals Ahiaruhe Tephra). It has a tilted but still well-defined depositional surface at the top forming terraces, and passes laterally westward to thick blue-grey lacustrine silt with a moa footprint and also containing Mount Curl Tephra. The tephra indicates an age greater than 0.2 Myr for the the base of the Ahiaruhe Formation and less than 0.26 Myr for the top. Kawakawa Tephra in overlying loess indicates an age greater than 0.02 Myr. The three formations correspond to most of the time represented by the late Nukumaruan Stage, Castlecliffian Stage and early Hawera Series. We infer that their deposition was controlled by climatic fluctuations and associated glacioeustatic sea-level changes coincident with Milankovitch cycles, superimposed on secular vertical tectonic movements.