“Fugro was engaged to analyse the amplitude information from the acoustic data of the 3D seismic survey of the P-impedance properties (rock) density of the gas-charged reservoirs identified by the Heron-1 well,” MEO said.

By locating fracture-induced porosities, the P-impedance mapping helps identify sweet spots in the reservoirs. It can also find possible gas saturation, differentiating between gas and water-filled reservoirs.

Fugro integrated all available geoscience data – well, seismic and petrology – into a single model through a pre-stack inversion process to provide better characterisation of hydrocarbon reservoirs.

This helped reduce drilling risks by identifying gas-charged zones, according to MEO, which claims to be one of the first companies to use this process in Australia.

The mapping found a zone immediately under Epenarra – the Echuca Formation shale, which is a prolific hydrocarbon source rock in this region – had relatively lower impedance.

But the Heron Plover Formation was interpreted to have higher impedance, indicative of extensive fracturing, which would improve gas flow rates and gas saturation.

MEO said the Fugro inversion analysis had increased the explorer’s confidence in its mapping and interpretation of the target structures, the potential presence of hydrocarbons in the main reservoir units and optimal locating of the planned wells.

The company said the West Atlas jack-up rig has completed endurance testing, inspections and compliance approvals. The rig constructor, Kepel FELS released the completed rig to the owner, Seadrill, yesterday.

Handover to MEO is still expected on September 22. The rig will be loaded in Singapore on to the heavy transport vessel, the Blue Marlin, for delivery into Darwin harbour by the end of September.

The West Atlas will then be provisioned and wet towed to the Heron-2 site. MEO expects to spud the well on or about October 6.

Meanwhile, Fugro has also completed drilling shallow boreholes and recovering core samples at the Heron-2 site and each of the short-listed locations for the follow-up well – Heron-3B, Heron-3C and Blackwood-1.

The sampling provides soil stability data for the seafloor at each well location and estimates the seabed penetration for the legs of the jack-up rig.

Fugro will also drill deeper boreholes and recover core samples at the proposed sites of MEO’s LNG and methanol production projects on Tassie Shoal, some 25km east of NT-P68.

“The subsoil data from the shoal would allow immediate commencement of front-end engineering and design studies of the substructural elements for these projects, providing the 2007 drilling program confirms commercial gas resources in NT-P68, MEO said.