The Geological Map of Otago

As his geological survey proceeded, James Hector produced geological maps of the areas he explored, with the ultimate aim of producing a geological map covering the whole of Otago (including Southland). He was assisted by draftsman John Buchanan, who was to work for him for the next twenty years.

1865 Dunedin International Exhibition

Hector played a leading part in the organisation of the 1865 Dunedin International Exhibition, and contributed several displays based on his exploration during the preceding three years. The catalogue lists rocks, minerals, birds, woods, dried plants, as well as plans and maps. Exhibit 865 is identified as a “Geological Map of the Province of Otago with unpublished details of the West Coast district” at a scale of eight miles to one inch. Hector also supplied a similar map to Sir Roderick Murchison, which is now in the archives of the Geological Society of London.

The University of Otago map

The giant geological map at Otago University poses some interesting questions. Drawn on Whatman wove paper watermarked 1862, it is dated 1864 and attributed to Hector. Although widely believed that it was prepared for the Dunedin Exhibition, it is not the same as exhibit 865. Drawn at a scale of approximately four miles to one inch, it is twice the width of exhibit 865, over 1.5 metres across. At this size it would have been a striking feature of the exhibition, but there is no mention of such a map in the catalogue, nor in the judges’ report or in newspaper accounts.

A topographic map of Otago and Southland Goldfields at a scale of approximately four miles to one inch was published in Dunedin by Ferguson and Mitchell in 1866, and a copy “Geologically Coloured from Reconnaissance Surveys by Dr Hector”, dated 1866, is held in Archives New Zealand, Wellington (R17917204). The geological boundaries are very similar to those on the Otago University map.

However, there is one crucial difference. The topography of the mountainous parts of Fiordland was poorly known in the 1860s. The 1866 map does not show ridges or streams in areas that were unexplored. In contrast, the large Otago University map shows a detailed pattern of ridges and streams that correspond to later knowledge of the topography.

It is difficult to resolve the conflicting evidence, and further research is needed. It is possible that the map is a late 19th century copy of Hector’s 1864 or 1866 map plotted on a later topographic base map.

Lost and found

For many years the large Hector geological map was on display in the Geology Museum at the University of Otago, and is recalled by past staff and students.  In his unpublished memoirs, James Park (Professor of Mining from 1901-31) recalls that the Hector's large map of Otago had been on display at the university throughout his career.

In the late 1970s there was concern about deterioration of the map, leading to discussions with the Hocken Library about its repair and conservation. It was sent away for restoration with a grant from the Art Galleries and Museums Association of New Zealand, but little documentation has survived.

For over 25 years the map was overlooked. Around 2005, during research on Hector's Otago career by A.G. Hocken, it became clear that the map was missing, and was unable to be traced. Finally, in 2007 it was located in the Auckland Art Gallery, and returned to the Hocken Library.