By Choice and Neccessity: Integrated Non-Seismic Exploration in the Southern Georgina Basin

Ian Whitchurch¹, Clarke Petrick², and Andrew Mulder^3
1 Northern Territory Oil, Sydney, Australia
² Northern Territory Geological Service, Alice Springs, Australia
³ RPS Troy Ikoda, Perth, Australia

The Southern Georgina basin is a 100 000 square kilometer part of the Cambrian-era Centralian Superbasin.

Northern Territory Oil's leases comprise about 30 000 square kilometers, and have a total of about 200 km of existing 2D seismic in those leases, acquired by the previous leaseholder, Pacific Oil and Gas. New seismic will be expensive to acquire, both because both the onshore seismic crews in Australia tend to be booked and because the mobilisation and demobilisation will add approximately $400 000 to the cost of a program.

Two exploration wells by the pervious leaseholders showed oil, Randall-1 and Macintyre-1. This shows that hydrocarbons were formed from the high TOC Arthur Creek “hot shales”, and we know it migrated into and within our leases; the question is can we find where it was trapped at acceptable costs.

The exploration plan is to

• do a basin-wide analysis, to define what the source is, when was it producted, where could it have migrated to, and what could be the reservoir and seal couplet;
• reprocess the existing 2D seismic, especially around the Randall and Macintyre wells;
• look for remte evidence of trapped hydrocarbons near to our existing wells with shows by using a combination of satellite analysis of vegetation patterns and aeromagnetic and areoradiation data;
• look for surface indications of hydrocarbons by soil analysis;
• using electro-telluric and dense-packed surface gravity to establish enough hints of a structure near to Randall and Macyntire and justify seismic work.