Petrel Energy Ltd and its partner and Operator, Schuepbach Energy International LLC (SEI), is pleased to announce that the Cardozo Chico corehole has confirmed the existence of oil generation in the Piedra Sola block. The Cardozo Chico is the shallower of two coreholes being drilled as part of a 2,000 metre corehole programme, to assess the hydrocarbon potential of PRL’s and SEI’s very large 3.5 million acre concessions in the Norte Basin, Uruguay. Both coreholes spudded in the Piedra Sola block in early September 2013.
Corehole 1: Cardozo Chico E-1
The Cardozo Chico E-1 corehole which is still coring ahead at 620m intersected a 10m laminated shale at a depth of 457m. While more detailed analysis will be undertaken of this and other core samples when it is shipped to the US, three initial samples were analysed for their geochemical properties. Total Organic Carbon content (TOC) averaged 3.3% with a maximum value of 6% and amorphous kerogen averaged 53% with a maximum value of 70%. Maturation, based on vitrinite reflectance measured 0.76 to 0.78, which is within the peak oil window, and strong streaming fluorescence observed in two of the three samples confirming oil generation.
The shale is considered to be part of the Permian San Gregorio Formation and correlates favourably with the shale identified in the Canada de Charrua corehole drilled by ANCAP, Uruguay’s National Oil Company, earlier this year. This corehole discovered traces of oil in similar aged rocks just a few kilometres north of the northern boundary of the Piedra Sola Block and was the first indication of a working hydrocarbon system in the Norte Basin.
Petrel Energy’s Managing Director, Mr. David Casey said today: “While more work is still required, further confirmation of an active hydrocarbon system in a second Permian source and reservoir within these shale’s in excess of 100km from the Canada de Charrua well, in addition to the Devonian Cordobes shale, is very encouraging.”
Corehole 3A: Cerro Padilla E-1
The Cerro Padilla E-1 corehole, with a 1,250m prognosed total depth, reached 122 metres shortly after spudding with casing run and cemented in place for installation of a blowout preventer (BOP). Unfortunately the BOP supplied by the local drilling contractor was not to agreed specification and despite exhaustive efforts a replacement BOP had to be ordered from outside Uruguay, which has now arrived and is being installed.
David Casey said “While the delays to the deeper Cerro Padilla well are somewhat disappointing, given the encouraging and growing evidence of hydrocarbons, the additional depth of this well and its impact on potential reservoir charge, we thought it was important to work with our local contractor to ensure best practice and procedures were followed.”
He went on to say “Despite these delays we are confident some of the lost time can be made up as this rig will operate 24/7, and we are looking forward to the enhanced understanding of the basin that will result from the additional depth of this well. The delays are unlikely to impact scheduling of next year’s seismic programme with permitting and approvals processes already commenced. ”
Piedra Sola and Salto
Petrel’s Uruguay project, through its interest in Schuepbach Energy International LLC (SEI), covers two concessions totaling over 14,000 sq km (3.5 million acres) in the onshore Norte Basin. Both concessions have the potential to host very large unconventional and conventional oil resources in a virtually unexplored basin.
Petrel currently owns a 25% interest in SEI, a private US company, which holds a 100% working interest the Piedra Sola and Salto concessions. Petrel also holds two further options allowing the equity interest in SEI to be progressively increased to 60%. The first option allows Petrel to increase its stake to 51% through an additional investment of US$5.5 million. The first phase of an initial US$2.5 million exploration programme has been completed with acquisition of magnetotelluric (MT) data. The two coreholes in Piedra Sola will complete this programme.