The Kaiwera-Mimihau district, Southland, New Zealand, is partly mantled in loess a metre or more thick. Three soil series (Tuturau, Otaraia, and Rosemarkie) have been mapped in the loess. Tuturau soils, nearest the Mataura River, have similar sand-and silt-sized heavy minerals to Mataura River alluvium, indicating probable derivation from the Mataura River floodplain. Otaraia and Rosemarkie soils, which are further from the Mataura River, contain higher amounts of hornblende, similar to those in locally outcropping tuffaceous greywacke rocks, indicating that the local rocks were another source of loess.