Report on source rocks of oil in the southern Ruatoria area especially Hikurangi & Mata Survey Districts New Zealand.

Stratigraphical assessment of southern Ruatoria especially Hikurangi and Mata with mention of the structure and source rock potential. It is concluded that the black shales in the Rakauroa formation are by far the most probable source rocks of the gas seepages of the Ruatoria district; they could also be considered as a very promising potential source for generating commercial deposits of oil. The Maungatapere formation could be a potential source of oil, but it is less promising than the Rakauroa. It is also noted that the Cretaceous formations and Taitai are very unfavourable source rocks. It is recommended that no future examination be attempted in Hikurangi, Mata and Waipiro S.Ds, however, approximately 3 weeks work should be done in the core structures N of Gisborne. Report includes 6 pages of photographs.