A unit of Talisman Energy Inc., Calgary, has begun a cased-hole test program of the Oligocene reservoir at the Kurdamir-3 well on the Kurdamir block in the Kurdistan Region of Iraq.
Talisman (Block K44) BV drilled the well to 2,895 m about 5 km southwest and downdip of the Kurdamir-2 well in what the block coventurers interpret to be a thicker portion of the Oligocene reservoir. The Kurdamir-3 well penetrated the oil column without encountering the gas cap, said partner WesternZagros Resources Ltd., Calgary.
Talisman recorded oil shows and supportive log data indicative of oil over the majority of the Kurdamir-3 Oligocene section penetrated. The Oligocene comprises a gross interval of 372 m of naturally fractured marlstones and dolomitic limestones including an interpreted 194 m of porous reservoir interval.
By comparison, the Kurdamir-2 well penetrated a gross interval of 300 m of which 140 m comprises the Oligocene porous interval. Coring and wireline logging operations have ended, and the wellbore is cased with a 7-in. production liner in preparation for testing. No evidence of formation water has been detected.
In the first well test at Kurdamir-3, Talisman will perforate the deepest interval between 2,776 and 2,788 m. Based on initial logging results, WesternZagros believes that the lowest known oil could extend 150 m deeper than that proven in Kurdamir-2.
The test program will then move uphole to focus on testing the potential of the porous reservoir section. WesternZagros expects to complete the Oligocene testing program in the second half of August.
Meanwhile, the 184 sq km Kurdamir block 3D seismic survey has been completed in order to define more clearly the areal extent of the Oligocene, Eocene, and Cretaceous reservoirs. Following the completion of seismic operations on Talisman’s neighboring block, the seismic crew will shoot a 3D survey on the northern part of the Garmian block in August.
The North Garmian survey will cover 258 sq km to define more clearly the areal extent of the Oligocene reservoirs. The North Garmian and Kurdamir 3D surveys will be combined to provide contiguous seismic coverage in order to determine whether the Oligocene reservoir is connected as one large structure across the two blocks. The data will be used to decide on future appraisal and development well locations and to refine resource assessments.
Elsewhere on the Garmian block, a crew is rigging up to drill the Baram-1 well with an anticipated spud date in the first half of August. Baram-1 will explore the potential extension of the oil leg discovered in the Oligocene reservoir of the Kurdamir structure onto the northern part of the Garmian block. Drilling time is 5 months to planned total depth of 3,800 m.
WesternZagros said Baram-1 “is the highest impact well of the 2013 drilling program and has the potential to add gross unrisked mean contingent resources of up to 200 million to 300 million bbl of oil equivalent in the Garmian block and, if the structure is shown to extend onto the existing Kurdamir discovery, an additional 500 to 600 MMboe in the Kurdamir block.”
Also on Garmian, the Hasira-1 appraisal and exploratory well is drilling ahead at 1,860 m after setting 20-in. casing at 1,014 m. The next casing point is at 2,050 m. Setting the third intermediate string of casing is planned for 3,900 m, just above the Jeribe reservoir, before drilling to a planned total depth of 4,100 m in the Oligocene reservoir.
WesternZagros plans to complete the well either in the Jeribe or the Oligocene reservoir depending on drilling and test results. Drilling time is estimated at 7 months.
Also on Garmian, WesternZagros drilled two of the planned three wells in the Upper Bakhtiari formation. This shallow, inexpensive well program recovered formation water and oil and gas at subcommercial rates. The wells have been suspended, the third well canceled, and the rig released.
The Upper Bakhtiari program was exploring low-cost oil production potential in the South Garmian area but was not viewed as a high-potential program to add greatly to the Company’s resource estimates.
(Source: Oil & Gas Journal)