Assessing New Zealand's Petroleum Endowment: The Atlas of Petroleum Prospectivity

Abstract

Where, in New Zealand's extensive offshore territory (Zealandia), does the geological evidence indicate that new petroleum fields are likely to be discovered, and which of New Zealand's numerous offshore sedimentary basins will host the next commercial discovery? A recently-initiated 4-year Government-funded research programme at GNS Science aims to address these questions by providing readily accessible digital maps in GIS format (with associated metadata) of potential subsurface petroleum habitats to aid conceptual development of exploration targets. The “Atlas of Petroleum Prospectivity” (APP) programme will synthesise the wealth of existing and new data, information, and knowledge within GNS Science and other open-file sources, to produce a nationally-significant baseline reference dataset that summarises in one place, for the first time, the current understanding of our geologically complex offshore petroleum basins. It will provide a consistent template for evaluating petroleum prospectivity within and between basins across Zealandia. It will also provide a basis for promulgation and technical administration of exploration permits and for identifying where new geoscience data and interpretations are required to better demonstrate petroleum potential. The APP will deliver a series of digital maps of all key petroleum systems elements in NZs offshore sedimentary basins. Map layers will include total sediment thickness, paleogeography, basement lithology, source and reservoir rock distribution, source rock maturity, heat flow, structure, trap distribution, and other salient information. We are adopting a “common risk segment” approach to delineate exploration play fairways, evaluate areas of highest prospectivity, and identify areas with poor data control or availability. Petroleum systems in each basin will be evaluated and calibrated with respect to previous exploration drilling successes and failures. The APP will provide a basis for developing new exploration concepts and strategies in the increasingly sophisticated search for new petroleum reserves. Compilation and assessment of the NW basins (Taranaki-Northland-Reinga) is well underway, and compilation and mapping of the SE (Great South-Canterbury) and eastern basins (Pegasus-East Coast-Raukumara) has commenced. Basins of the “far frontiers” will be progressively assessed in coming years. Programme outputs will be released via a web-server (e.g., GNS Science's Petroleum Basin Explorer) and data packs.

AAPG Datapages/Search and Discovery Article #90217 © 2015 International Conference & Exhibition, Melbourne, Australia, September 13-16, 2015