Explanatory notes to accompany New Zealand Soil Survey report 6

Content Partner: Manaaki Whenua – Landcare Research. Loess is widespread in central and southern North Island where it covers large areas of terraces and rolling hills. In places it is up to 15 m thick and, where it covers old landscapes, it usually consists of several beds demarcated by paleosols, indicating that there were several periods of loess deposition, each followed by an interval of weathering and soil development. Loess is an important parent material of both present-day soils and paleosols in the North Island, and there is much research into its nature, chronology, and detailed distribution. These notes and the accompanying 1 : 1 000 000 map of surface deposits of loess summarise the distribution and nature of loess deposits in the North Island. They have been compiled from information taken from publications by Fleming (1953, 1972), Cowie (1964b, 1968), McCraw (1967), Rhea (1968), New Zealand Soil Bureau (1968), Vucetich & Pullar (1969), Milne (1968, 1973a, 1973b, in prep.), and Pullar (1972); and from information obtained by current and past soil surveys by Soil Bureau, DSIR, and by J. D. G. Milne during recent field work in the Rangitikei drainage basin of south-western North Island. Much of the available information concerns loess in the Rangitikei and Manawatu districts of the south-western North Island, and consequently many of the statements about North Island loess are generalised from the loess sequence in these districts.