March 14, 2007


Description

 

The original Mars A-14 well was drilled and completed in 1996. The well was worked over in 2000 because of a sand control failure. In 2003, the A-14 was again shut in due to increased sand production with concomitant decreased oil production. In 2004, after the slot had been recovered, the M1/M2 objectives were re-drilled.

Because of depletion and wellbore geometry, development drilling after years of production has become increasingly challenging. It is unavoidable to intersect both depleted and virgin pressured sands in the same interval. The high mud weights required for wellbore stability coupled with a narrow Pore Pressure / Frac Gradient window potentially subjected the well to the loss circulation – stuck – kick cycle, making any sidetrack an expensive and potentially hazardous endeavor.

Three sidetracks in close proximity to one another in the Gulf of Mexico in 3,000 feet of water were drilled into the same production horizons on the Mars Tension Leg Platform. Forty seven drilling days were spent attempting to drill Sidetrack01 with 61% of that time attributed to unplanned non-productive activities that included wellbore instability, lost circulation, and kicks. Over 6,000 barrels of synthetic base mud were lost to formation.

Nearly 32 days were spent attempting Sidetrack02 with 60% of the time attributed to unplanned non-productive time; primarily lost circulation and wellbore instability. Over 3,000 barrels of synthetic base mud were lost.

Both Sidetracks 1 and 2 were drilled in the conventional manner – overbalanced and in an open vessel. Managed Pressure Drilling equipment and techniques were employed to drill Sidetrack03 over a 33 day period. Seepage accounted for losses of 600 barrels of synthetic base mud. There were no recorded incidents of lost circulation, kicks, or wellbore instability that would have otherwise interrupted drilling operations. Unplanned non-productive time was less than 2%.

Significant improvement in drilling efficiencies were realized utilizing Managed Pressure Drilling technologies. A direct comparison of equipment and operational technologies will be discussed.

 


Featured Speakers

Speaker Ken Malloy
Staff Consultant Mohr Engineering Division of Stress Engineering Services   Ken Malloy is a graduate of the University of Houston and a Registered Professional Engineer. He has a long-standing interest in safe managed pressure drilling and underbalanced operations, drilling efficiency, HPHT issues, and well control. He has led numerous investigations ...

Staff Consultant
Mohr Engineering Division of Stress Engineering Services
 

Ken Malloy is a graduate of the University of Houston and a Registered Professional Engineer. He has a long-standing interest in safe managed pressure drilling and underbalanced operations, drilling efficiency, HPHT issues, and well control. He has led numerous investigations into root causes of equipment and operational failures.



He is a member of the IADC’s Underbalanced Operations and Managed Pressure Drilling Committee. He is also an active member of the American Association of Drilling Engineers, the Society of Petroleum Engineers, and the American Petroleum Institute; where he is Chairman of the Work Group studying the mechanics contributing to casing wear.



Malloy is co-investigator and project manager for joint industry project DEA155, a risk assessment study of managed pressure drilling. He is presently employed at Mohr Engineering, a Division of Stress Engineering Services in Houston.



 


Full Description



Organizer

Joe Wallace


Date and Time

Wed, March 14, 2007

11:30 a.m. - 1 p.m.
(GMT-0500) US/Central

Event has ended

If you do not have a full-time job in the oil and gas industry, are a full-time student or Member in Transition (MiT) member, and you do not see a discounted registration fee for students/MiT regarding this event, please contact the GCS manager at spe-gcs@spe.org.


Location

Greenspoint Club

16925 Northchase Drive
Houston, TX 77060
USA