In the Otago Coal Region, Late Cretaceous sub-bituminous and lignite coal measures are present in eastern Otago, with the Kaitangata Coalfield the major deposit. Large lignite deposits of Miocene age are present in Central Otago. These lignites are of Miocene age. 6256 Mt recoverable. Coal at much greater depth within onshore and offshore sedimentary basins is the major source rock for New Zealand's petroleum resource.
Peat deposits are present in coastal plains throughout mainland New Zealand.
They are worked for horticultural use in the Hauraki Plains and Southland. Large peat deposits in the Chatham Islands have a high wax content, and have potential for wax extraction or conversion to liquid fuels. In 1992, 2.9 Mt of coal was mined within New Zealand. Coal exports continue to grow with over onequarter of the annual total coal production currently being exported. Today, most of New Zealand's high-quality bituminous export coal comes from the Buller Coalfield, and a proposal to mine coal for export is under investigation in the Greymouth Coalfield.