CATEGORIZED | News

Regulator: Industry must not get complacent about UKCS well control

Posted on 19 March 2009

Among the myriad results of the study, it was found that the total number of kicks over the last 10 years were evenly spread among the Southern North Sea, North North Sea, Central North Sea and Moray Firth. But when the data is corrected for the level of rig activity, it becomes evident that the southern region had the highest kick frequency.

This was in line with the results from dissecting incidents by rig type – it was found that jackups had the highest frequency of kicks experienced. Almost all wells in the Southern North Sea, exclusively a gas province, are drilled using jackups.

For development wells and for exploration and appraisal wells, the trends were markedly different. For the first category, the Northern North Sea had the highest number of reported kicks during this period, with a significant portion of them occuring during workover operations.

Mr Dobson explained that a major factor for this is because reservoirs in the northern region are typically Jurassic sandstone. Faulting is common, often with discrete fault blocks with little or no communication between them. The sands are also deltaic, and reservoir sands are frequently inter-bedded with shales, also with little to no communication. A significant number of kicks during workover occur because of a loss of kill fluid to adjacent depleted sands with the loss of head allowing a less depleted sand to flow.

For exploration and appraisal well kicks, the majority were concentrated in the Central North Sea and Southern North Sea regions. In the Central region particularly, this is where a majority of the UK’s high-pressure, high-temperature wells have been drilled. Many kicks since 2006 were due to encountering higher than expected formation pressures or by swabbing, mostly in HPHT wells.

Overall, the study was able to help the regulator spot trends and showed that the majority of incidents were “benign,” caused by complex geological factors. But Mr Dobson pointed out that human error continues to be a factor in well incidents: “We must avoid complacency.”

SPE/IADC 119942, “Kicks in Offshore UK Wells – Where Are They Happening, And Why?” by JD Dobson, Health & Safety Executive, was presented at the 2009 SPE/IADC Drilling Conference, 17-19 March, Amsterdam.

Leave a Reply

*

FEATURED MICROSITES


Recent Drilling News

  • 26 January 2015

    Young professionals program at SPE/IADC Drilling Conference to target future leaders of the industry

    The oil and gas industry is constantly looking to the future. Whether this comes in the form of pushing the limits of pressure...

  • 22 January 2015

    Tullow Oil moves ahead with exploration, appraisal drilling onshore Kenya

    Tullow Oil has announced updates on several onshore projects in Kenya, including the Expir-1 exploration, Engomo-1 exploration, the Ngamia and Amosing...

  • 22 January 2015

    Petrobras reduces operating costs, time with new pre-salt subsea equipment deployment technique

    At the end of last year, Petrobras deployed its first wet Christmas tree using cables in the pre-salt area. The main change involved was the use of a subsea equipment...

  • 22 January 2015

    XACT, BP complete first deepwater deployment of SandSentry Acoustic Telemetry Network in Gulf of Mexico

    XACT Downhole Telemetry, in conjunction with BP, recently completed the first operational field trial of the SandSentry Acoustic Telemetry Network in the deepwater Gulf of Mexico...

  • 21 January 2015

    University of Houston to lead subsea engineering research center

    The University of Houston (UH) will lead a national research center for subsea engineering and other offshore energy development issues, including research and technology…

  • Read more news