Using the M/V Orient Explorer seismic vessel, PGS will acquire and later process about 500 square kilometres of 3D seismic data over the crest of the Epenarra prospect in the central part of the permit.
Last month, Multiwave Offshore Services, which is a subsidiary of Compagnie Generale de Geophysique (CGG), won a contract to acquire about 600km of 2D seismic data over the Blackwood lead in the northern part of NT/P68.
The 3D survey, which was recently expanded from 410sq.km to 500sq.km, is scheduled to start on September 13, according to Methanol Australia.
It is designed to identify the density, distribution and orientation of faults and fracturing in the 50m gas-bearing zone intersected 34 years ago by the Heron-1 exploration well.
The survey will also determine the best place to drill an appraisal well, planned for late next year, to test the productivity of this interval.
The expanded survey will also improve the imaging of the deeper Heron North and South Plover Formation structures. Subject to confirmation by appraisal drilling, the potential gas resource could underpin the company’s proposed LNG and methanol projects.
The Epenarra structure is a broad, low relief anticline at the Darwin Formation level with a mapped closure of about 1200sq.km. The formation has been estimated to contain 5620 billion cubic feet of P50 reserves.
Heron-1, drilled by ARCO in 1972, recorded several interpreted gas-bearing zones, including a 50m fractured carbonate interval in the lower section of the Darwin Formation. Studies indicate that the gas quality at this level may be low in carbon dioxide with the possibility for attractive levels of associated condensate, Methanol Australia said.
