GNS Science

The Petroleum Exploration Geoscience Initiative (PEGI)

The Petroleum Exploration Geoscience Initiative (PEGI) has produced a web portal to the country's oil and gas exploration data and may be the most data-rich and interactive of its type in the world.

Completed in March after two years work by GNS, the system pulls together knowledge on New Zealand's sedimentary basins and petroleum systems. The suite of products developed includes the geochemistry of oils and gas condensates in those basins, seismic and metadata, data on reservoir properties, and comprehensive bio- and chrono-stratigraphy for key wells.

The Petroleum Basin Explorer was developed by adding 14 new GNS Science products to eight already available. Interactive web-based map tools within the explorer include the NZ Exploration Map, the Frontier Exploration Map and Offshore Prospectivity Atlas.

GNS says the resulting data are easy to use, linked geographically and free, and have been accessed by interested parties worldwide. By the end of May, 154 external registered users had logged on, including 43 exploration company staff and 28 consultants.

The $7.8 million development, jointly funded by GNS and the Ministry of Economic Development, involved 15 distinct projects and more than 60 staff.

In total, PEGI accesses and indexes more than 0.5 terabytes of New Zealand petroleum data, excluding well logs and raw seismic data. Some of the material, sourced from GNS, New Zealand Petroleum & Minerals, the National Institute of Water & Atmospheric Sciences, and Land Information New Zealand, was previously either difficult to find or inaccessible.

New techniques

The project has also involved the development of a number of techniques new to New Zealand and globally, and generated large amounts of new analytical data and added new insights into the country's petroleum systems.

A method developed to quantify the absolute maturities of oils and gas condensates using multivariate regression of source rock extracts data was a world-first, GNS says. Absolute maturities have been determined for most of the 239 oils and gas condensates in the PEGI databases.

Comparing the molecular fingerprints of petroleum samples and source rocks has seen new oil-to-oil and oil-to-source rock correlations developed which have in turn provided important insights into the country's petroleum `plumbing' systems, particularly in the Taranaki Basin.

They include indications that oils and condensates from the Kapuni and Kupe fields are almost certainly derived from the same `kitchen' area.

Oils and condensates from the Rimu and Kauri fields are from older source rocks than any other Taranaki discoveries to date, while production from the Maui and Tui fields also appear to be from separate and disconnected charges.

GNS says new oil and gas resources can only be discovered through drilling. But it says successful petroleum discovery is predicated upon the availability of high‐quality technical data, upon which informed exploration decisions can be made.

By improving awareness of New Zealand's unique petroleum geology, PEGI will help to reduce the geological uncertainty and financial risks associated with oil and gas exploration. It may also significantly reduce the time and cost that exploration companies need to invest before deciding whether to commit to exploration here.

As a result, PEGI may help New Zealand gain a competitive advantage in the global exploration market, ultimately supporting an increased rate of oil and gas exploration, hopefully to be followed by new discoveries.

The Energy Project of the Year award category is sponsored by ITL.