Major new geological map series is completed - 23/04/2012
An 18-year-long project to produce a new series of geological maps of New Zealand has just finished.
Known as QMAP (Quarter million scale map), the project started in 1994 and has produced 21 geological maps covering all parts of New Zealand.
The series replaces earlier maps, mostly made in the 1960s, and has brought many improvements in accuracy and interpretation, as well as a versatile range of digital map products.
The series is a world-first example of a national geological mapping project conceived and implemented using the GIS technology.
The published maps have been popular with about 11,000 copies sold so far and increasing demand for digital data derived from the maps.
End users include local and central government, engineering consultants, utility companies, developers, mineral and oil exploration companies, universities, schools, and the public.
The GIS information layers with each map can be searched, analysed, and portrayed in a variety of ways to suit different applications.
The geological maps are accompanied by attractive explanatory texts that describe in more detail the geology of each area. Each map book contains information on the geomorphology, stratigraphy including detailed rock unit descriptions, tectonics, engineering geology, geological resources and geological hazards with extensive references to available geological information.
The texts are well illustrated and include superb aerial photographs by renowned landscape photographer Lloyd Homer.
Programme Leader Mark Rattenbury said accurate geological maps were a basic information resource for every country.
“They provide essential information for infrastructure planning, and for the development of mineral, petroleum, and groundwater resources,” Dr Rattenbury said.
“They also identify geological hazards such as active faults, potential landslides, and liquefaction-prone areas. They provide essential background information for assessing ground conditions at building sites and for urban planning decisions.”
Typically up to nine of the 21 maps were in various stages of preparation at any one time. Such was the level of detail, it could take up to five summer field seasons plus office and laboratory work for a team of two or three geologists to complete each map.
The maps were compiled from existing data wherever possible, but the geology of many areas of the country was relatively poorly known and significant time was spent undertaking fieldwork. Major campaigns were mounted in the more remote areas such as Stewart Island, Fiordland, the Southern Alps, and North Island’s axial ranges.
Dr Rattenbury said fieldwork had been a highlight of the project with geologists visiting little known parts of country and making many new observations of the rocks and geological structures.
“This has resulted in a much more even coverage of our knowledge of New Zealand’s geology.”
Geologists collected more than 10,000 rock samples during the fieldwork and these have been added to GNS Science’s National Petrology Reference Collection where they would be permanently available for reference and other research.
The QMAP project had been funded by the Foundation for Research, Science and Technology and its successor, the Ministry of Science and Innovation, through a series of research programme contracts.
Support from the two government agencies had been essential for the successful completion of the project, Dr Rattenbury said.
He believed the $25 million investment in the project would benefit New Zealand for many decades to come.
“Without the support of the geology departments of our universities this project would not have been possible,”
Geologists and technicians from GNS Science’s Lower Hutt and Dunedin offices undertook most of the work. They benefitted from access to thesis and other research data from all New Zealand universities.
“Without the support of the geology departments of our universities this project would not have been possible,” Dr Rattenbury said.
Some external specialist expertise had been crucial for compiling the geology of Stewart Island, Fiordland, Nelson-Marlborough and Northland.
A seamless GIS dataset, combining the 21 map sheets, is currently in production and is expected to be available in digital form by July 2012. It will meet requirements for fundamental geological coverage for New Zealand into the future.
With the conclusion of the QMAP series, the focus of new geological mapping research has shifted to more detailed maps of urban areas, beginning with Christchurch, and of areas with mineral, coal, petroleum, geothermal and groundwater resource potential, to support the exploration and management of our natural resources.