Henderson, J.; Ongley, M. 1920 The geology of the Gisborne and Whatatutu subdivisions, Raukumara division. Wellington: Government Printer. New Zealand Geological Survey bulletin 21 88 p.
Abstract: The area described includes the survey districts of Uawa, Waikohu, Waimata, Patutahi, and Turanganui, and may for convenience be termed the Gisborne subdivision. In addition, a hurried examination was made of Waingaromia and Mangatu survey districts to check the results of a survey carried out in 1908-9 by J.H. Adams. The united subdivisions contain in all an area of about 1102 square miles. They consist for the most part of deforested uplands that rise from 800 ft near the coast to an average height of about 1,600 ft along the western and northern borders of the district. Farther westward the land rises to over 3,000 ft above sea level and forms the main divide of the North Island. A portion of this highland enters the north-west corner of the Whatatutu subdivision, where peaks nearly 4,000 ft in height occur. The area examined is essentially an agricultural and pastoral district, and practically the whole of it is now being so utilized. Surface indications of oil are suggestive of hidden mineral wealth, but up to the present attempts made to find petroleum in commercial quantities have been unsuccessful. (auth/DG)