Spudded on February 10, the Mira-1 core hole intersected eight metres of coal in the Bandanna Formation, after drilling reached a total depth of 252m on February 13 using the Mitchell Drilling Contractors Rig 120, Comet Ridge said.
Two drill stem tests were undertaken, one over the Castor seam and one over the Pollux seam. Both tests indicated presence of permeability, according to Comet Ridge.
On February 17, Santos used the same rig to start drilling Humboldt-1, which reached a total depth of 253m two days later.
About 4.5m of coal was intersected in the Bandanna Formation. A drill stem test has been run over the Pollux seam, with indications of permeability, and a second drill stem test will be conducted over the Castor seam, Comet Ridge said.
The DST results from the two core holes are currently being analysed by operator Santos.
Currently, all coal cores are degassing and undergoing desorption testing. Comet Ridge said final results of gas content and saturation are expected in the coming months.
Mahalo-2, the third well in Comet Ridge’s Phase II earning program, is due to start drilling mid-year, after the joint venture last week decided to source a different rig.
Mahalo-2 will initially be drilled to a point immediately above the Bandanna Formation coals to assess its productivity and provide initial reserves for the project, acording to Comet Ridge.
The company said the three wells – Mira-1, Humboldt-1 and Mahalo-1 – would fulfil its earning obligations, entitling Comet Ridge to a 40% interest, with Santos and Origin Energy each owning 30%.
In March last year, Santos determined potential volumes of gas in place, ranging from a minimum 181 billion cubic feet up to 990 BCF.
But Comet Ridge said the most likely volume is estimated to be more than 400 BCF. After considering a 40% recovery rate, the company said between 70 and nearly 400 BCF of gas might be recovered.
However, recovery factors of 60% to 70% have been recorded in several US CSM developments, it said.
Gas reserves developed within the ATP are well positioned to be transported into the significantly increasing Gladstone gas market, Comet Ridge said in an earlier report.
The Mahalo Project, about 100km north along a structural trend, targets the same productive coal seams as those produced at the Spring Gully and Fairview CSM gas fields in central Queensland.
The Spring Gully and Fairview CSM gas fields contain 1300 petajoules of proven reserves and 1947PJ of proven and probable gas reserves.
The Northern Denison Trough gas pipeline, part of the Wallumbilla-Gladstone pipeline, passes through the western edge of ATP 337P.
