Holders of interests in the Coiron Amargo Block in Argentina’s Nequen basin and a unit of Royal Dutch Shell PLC have entered a series of agreements that would subdivide the southern part of the 100,000-acre tract and adjust holdings and roles (OGJ Online, Nov. 12, 2013).
The block has conventional oil production from the Jurassic Sierras Blancas formation and unconventional potential in the Lower Cretaceous Vaca Muerta shale. It’s divided into a northern exploitation concession of 26,598 acres and a southern evaluation concession of 72,738 acres.
According to Madalena Energy Inc., Calgary, which holds a 35% interest in the total block, the agreements would divide the southern concession into two evaluation lots: Coiron Amargo Southeast and Coiron Amargo Southwest.
Parties to the agreements, in addition to Madalena, are Shell unit O&G Developments Ltd. SA, not previously an interest holder in the block; ROCH SA; Apco Oil & Gas International Inc., a subsidiary of Pluspetrol Resources Corp.; and provincially owned Gas y Petroleo del Nequen SA.
Subject to governmental approvals, Madalena will assign its interest in Coiron Amargo Southwest to the counterparties and increase its working interest in Coiron Amargo Southeast to 90% and become operator. Gas y Petroleo will retain its 10% working interest in Coiron Amargo Southeast.
Madalena will continue to hold a 35% working interest in the northern exploitation concession, where Apco will become operator.
ROCH has been operator of the Coiron Amargo block with a 10% interest. Besides the ROCH and Madalena shares, interests before the new agreements take effect are Apco 45% and Gas y Petroleo 10%.