www.centralpetroleum.com.au
Central Petroleum (ASX: CTP) holds an extensive package of prospective acreage of over 270,000 km2 in central Australia, which is predominately in the Pedirka Basin, along with 25,000 km2 in the Southern Georgina Basin.
Apart from conventional gas potential, the company has had independent estimates of over 10,000 trillion cubic feet in UCG "syngas" prospective recoverable resources.
Central Petroleum to flow test Surprise-1 well this week
Central Petroleum (ASX:CTP) will flow test the Surprise-1 re-entry well late this week to gain an understanding of the potential flow rate and prospectivity of the well.
Over 230 metres of horizontal drilling of Surprise met with continuous oil and gas shows in sandstone completed.
Gross vertical thickness of continuous oil shows of approximately 28 metres were encountered.
A Measured Depth of around 2,854 metres with a True Vertical Depth of approximately 2,534m has been reached in the target reservoir.
Tight hole conditions have developed in the angle build section of the wellbore and consequently further drilling has been discontinued to safeguard the well integrity.
It is planned to run a sleeve of 2.875” production tubing through this section to counter sloughing claystones and siltstones of the Middle Stairway Sandstone Member before testing commences. This will prevent any problems during testing and possible subsequent production.
Throughout the horizontal drilling, while dip changes were encountered the drill bit remained in sandstone with continuous oil shows and during only approximately 10 metres of horizontal drilling were oil shows rated "at less than good to excellent."
100% dull to bright yellow fluorescence and instant blue/white cut fluorescence were commonly recorded.
A drill break was evident at 2,676m Measure Depth. On circulation to the surface, black oil was evident on the shale shakers and a gas peak of 1,167 units was recorded.
Similar “heavy gas” dominated recordings were evident throughout drilling and circulation averaging in excess of 30-50 units with occasional much higher peaks.
Most of the time during drilling and circulation, free oil droplets were observed in the drilling fluid; on occasion covering approximately 60% of the surface of samples taken.
