Offshore staff
CALGARY, Alberta -- Cirrus Energy Nederland has confirmed a commercial-quality gas accumulation in the North Sea which could be developed from the M7-A production platform.
The deviated M07-07 well, drilled from the platform, encountered the top of the prognosed Jurassic sandstone reservoir at a TVD of 2,792 m (9,160 ft) subsea. Cirrus says the true vertical gross thickness of the drilled reservoir section is 48.7 m (160 ft), the upper part of which is gas bearing, with an interpreted gas/water contact at 2,816 m (9,239 ft).
Early petrophysical analysis suggests average porosities of 9-12%, with an average net to gross ratio of roughly 50% over the reservoir interval. Permeability ranges from 0.1-10 md. Further analysis is in progress of both core and log data to improve quantification and understanding of the reservoir’s petrophysical parameters.
The M07-07 appraisal well tested at a stabilized rate of 10 MMcf/d with a flowing well head pressure of 110 bar (1,600 psi) through a 36/64-in. choke.
Following the initial clean-up test, however, Cirrus discovered that a permanent packer in the completion had failed, was leaking, and needed to be replaced. A workover was performed to replace the packer, but there was damage to the formation as a result of exposure to fluids used to kill the well, and only minor gas flow rates have since been measured.
Because of the low productivity resulting from formation damage, and the proximity of the gas/water contact, the existing wellbore is unlikely to be used for production. However, the well did meet its pre-drill objective. Cirrus will perform detailed engineering design and planning to optimize design of a potential future sidetrack of the M07-07 well.
Cirrus President David Taylor said: “The M07-07 well has established that there is a potentially substantial additional gas accumulation which can be developed and produced via the existing M07-A production platform and export infrastructure. With the substantial amount of data acquired from the M07-07 well, detailed work will now be undertaken to optimize the development of this new pool.“
08/31/2010