UK-based Corallian Energy has begun drilling operations on the Colter appraisal well, using one of Ensco’s jack-up drilling rigs.
Corallian is the operator of offshore license P1918 which contains the Colter oil discovery located two kilometers south of Wytch Farm – Europe’s largest onshore oil field.
Initial discovery of the prospect was made in 1986 in the Sherwood Sandstone reservoir, the same play that has proven to be productive at Wytch Farm where over 450mmbbls have been produced to date.
The start of drilling operations on the appraisal well was reported by United Oil & Gas and Baron Oil, Corallian’s partners in the license.
United said that the well, designated Colter 98/11a-5, was spudded at 10:10h on February 6, 2019.
The Colter well is being drilled using the Ensco-72 drilling rig, contracted by Corallian for a two-well back-to-back program on Wick and Colter prospects.
The well is expected to take around three weeks to reach a planned total depth of 1,830 meters.
The company added that Colter would be drilled updip of the 98/11-3 well, which initially discovered the prospect. Gross un-risked mid-case oil contingent resources in the section proven by the 98/11-3 well have been estimated at 4mmbbls, with gross un-risked mean-case prospective resources estimated at 15mmbbls in the rest of the structure.
United Oil & Gas CEO, Brian Larkin, said: “Colter is the second well United has participated in within the last twelve months, the first being the successful Podere Maiar well at the Selva gas field in Italy.
“Targeting a historic discovery on the same play as the nearby prolific Wytch Farm Field and with an aggregate mid-case volume of 19 mmbbls of gross contingent and prospective resources, we believe Colter offers an excellent opportunity to emulate the success we enjoyed with Podere Maiar.
“Following our first competent person’s report covering the Crown oil discovery in the North Sea and the Waddock Cross field in the Wessex Basin, and with CPRs due for our offshore Jamaica and onshore Italy projects, we believe that 2019 is the year in which we will unlock the significant potential of the diverse portfolio that we have built.”
In a separate statement, Baron chairman and CEO, Malcolm Butler, said: “With gross, unrisked, recoverable mean prospective resources of 23 million barrels of oil equivalent, estimated to be present in the Colter structure by Corallian, success with this well will have a material impact on the value of the company.
“[The 98/11-3 well] discovered a 10.5-meter oil column in the Triassic Sherwood Sandstone, the main reservoir in nearby Wytch Farm oilfield, and 98/11a-5 is being drilled in a position which is interpreted to be significantly higher at Sherwood Sandstone level than the 1986 discovery.”
It is worth reminding that Corallian’s Wick exploration well located in License P2235 off the UK, completed in January, came up dry.