The upgrade followed ongoing analysis of data, which revealed the underground Bottom Zone reservoir comprised a highly permeable fracture system with a much larger fluid volume than indicated prior and translating into a porosity thickness of 4.4 metres.

De Graaf, said depending on circulation test results, the upgrade justified developing a small demonstration plant.

Geodynamic has also developed a new reservoir 135 metres above the underground Bottom Zone, following hydraulic stimulation of fractures from Habanero-2.

The new Top Zone reservoir intersected the Habanero-1 well near the bottom of the casing, but Graaf said connecting the two wells by perforating the casing at this level for testing had been postponed until the Bottom Zone’s circulation test was complete.

Graaf said final evaluation of the Bottom Zone reservoir was hampered by a locally impaired connection between the Habanero-2 open hole section and the Bottom Zone reservoir.

Plans to improve this included a clean up program over several weeks, which included flow from Habanero-2 while injecting into Habanero-1 to further stimulate the Bottom Zone. Friction within the well completion tubing limited the injection rates to about 40 litres per second.