Miocene oil pay buoys Coastal off Thailand
Coastal Energy Co., Houston, will divert a mobile offshore production unit to its Bua Ban North B field in the Gulf of Thailand to begin testing well in the Miocene reservoir discovered in 2010.
By OGJ editors
HOUSTON, May 25 -- Coastal Energy Co., Houston, will divert a mobile offshore production unit to its Bua Ban North B field in the Gulf of Thailand to begin testing well in the Miocene reservoir discovered in 2010.
Two Bua Ban wells found oil in Miocene in 2010, the first time productive Miocene sands have been encountered in the Songkhla basin.
Coastal will case its most recent well, Bua Ban North B-05, which went to 7,600 ft true vertical depth and cut 178 ft of net pay with 27% average porosity in the Miocene objective. The company will then spud the B-04 well to appraise the Miocene reservoir updip from B-01 discovery well.
As it diverts the MOPU from Bua Ban North A to begin testing Bua Ban North B first, Coastal is procuring a second MOPU for Bua Ban North A for arrival in the third quarter of 2011.
Coastal said, "The B-05 well was designed to encounter maximum net pay by drilling along the bounding fault plane within a single structural trap. The Bua Ban North A-03 well was drilled with a similar well design and had similar results. We plan to utilize this drilling technique in future wells to optimize pay zones.
“The results of the B-05 further validate the tremendous upside potential of the Miocene trend in the Songkhla basin. Based on recent drilling results, we believe the Miocene trend extends into the central part of the basin and becomes shallower as it moves east. Once appraisal work is completed at Bua Ban North B and testing has begun, we plan to move the rig to a new location further to the east to continue exploring the Miocene trend.”
The company’s production averages 8,500 b/d offshore and 2,000 b/d of oil equivalent onshore. Bua Ban field, which went on production in mid-2010, produces from Oligocene and Eocene reservoirs.
Production at Songkhla A field has fallen due to declining rates from the wells drilled in the previous two quarters. The three wells discovered new Oligocene and Eocene reservoirs that are not in communication with the main Songkhla reservoir and consequently are not benefitting from existing water injection wells.
The company will drill water injection wells on the new reservoirs to restore aquifer support and production rates once approval is received, which is expected within 2 months.