GSPC awaits high-temperature charges for Ambethi

Vol 10, PW 25 (19 Apr 07) Exploration & Production

Gujarat State Petroleum is awaiting the arrival of explosive charges that can withstand high temperatures before resuming tests at its successful Ambethi-2 well at CB-ONN-2000/1 near Ahmedabad, where it holds 50% alongside GAIL, which also holds 50%.

PETROWATCH learns that initial testing of Ambethi-2 was unsuccessful because the bottom hole temperature reached a searing 335 degrees Fahrenheit. “This is the highest temperature GSPC has ever encountered onland,â€‌ we are told.

“This caused problems during the test.â€‌ Confident of the well’s potential, GSPC decided not to abandon it, but instead to import charges that work in extreme temperatures.

These charges are expected to reach the site towards the end of this month (April). Ten days ago GSPC drilled Ambethi-2 to TD of about 3200 metres.

Oil shows were recorded from around 3000 metres onward, almost all the way to the final depth. GSPC plans to test an interval of between 50 and 60 metres with the high-temperature charges over a period of one week.

Examination of logs has already revealed a 40-metre oil pay. If confirmed by tests, it will be the thickest pay so far on this block, the most hotly contested of NELP-II.

Production is already underway, but not as much as GSPC would like. Under DGH instructions, it is producing just 350 b/d from one of three potential producers: PK-2, PK-2-A1 and PK-2-A2.

The other two are on observation till completion of a three-month study. These wells are producing from a fractured reservoir and the DGH is concerned that unless injector wells are drilled from the start the fractures will close during production.

Disagrees GSPC: “One month of production is already over and the fractures do not seem to be closing and there is no pressure drop.â€‌ More, GSPC tells us external consultants have told it that, contrary to what the DGH believes, injector wells are not necessary at the start of production.

“Two more months are left for the study,â€‌ we hear. “GSPC believes these three wells can safely produce 15,000 b/d.