APPLICATION OF PRODUCTION LOGGING & NOISE LOGGING FOR

WELL LEAK DETECTION, CASE STUDY IN PERSIAN WELLS

REZA SALEHI-MOORKANI, SPE, NISOC, & MARYAM MOHAMADIPOUR -SPE 141770-

Production Logging• Tools use to measures flow properties (P,T, ρ) • To diagnose the illness of old wells• Run through tubing • Detect the leaking pipe, leaking packers, fluid movement behind casing• Evaluate effectiveness of well treatment

Introduction of Field K• Oil reservoirs in Dezful Embayment, north of Persian Gulf• Discovered in 1970• Have 2 reservoir;-

Asmari reservoir-oil Bangestan reservoir – gas

• March 2009, a surface leak detected that could be seen around 600m away from the well location

• Observations of oil on the rocks • Run Noise Logging and Production Logging from surface to bottom to check the

downhole leak.

Well schematic

Noise Logging results

• Indicate that fluid flow is from Asmari formation behind 9 5/8” casing shoe

• Flow continues to moves behind casing up to 13 3/8” casing. & lost at depth 234m.

• Peak shows possible outflow fracture in the Mishan formation

• Casing leak identified at 2290.5m using other tools

• However, this leak not contribute too much on flow behind the casing in the well.

Production Logging results1. Flowing Survey- Spinner• Part A: from 1800m to bottom noisy

record• From 1780m to 690m, smooth

reading since only oil flow• From 3632m t0 1780m indicate

water column• Part B: gas effect• However, no traces of production

2. Density• Part A: ρ decrease from 1.1 g/cc to 0.9-1 g’cc,

shows that mixture of oil & water flow together.

• No indication of water production to surface.

3. Temperature• Part B:

❶sharp changes at 3632m due to openhole section.

❷at 690m shows release of gas

• No sign of leak

❷

❶

Shut-in Survey1. Spinner• Small decrease at 2290m• An inflow/outflow occurred • No sign of extending up to surface• Therefore, it might be a casing damage.

2. Density • ρ decrease as depth increases• This is due to temperature fall • Sharp change at 2290m because of

fluid falling back.

2. Temperature• At 2290m shows suspicious

inflow/outflow zone.• It is believed there is an inflow zone

at 2290m due to behaviour of density.

Conclusion • Run a pressure test to find the real source of leak by plugged in the openhole

section• It is proved that noise logging more accurate about the leak is from 9 5/8” casing

shoe.• Noise Logging can detect flow behind casing but cannot determine the type of

fluid flow.• Production Logging helps with noise logging helps to have better understanding

about leak points.

References • James J. Smolen. Cased Hole and Production Log Evaluation. PennWell Books,

1996.• Henri Cholet. Well Production Practical Handbook. Technip edition, 2000.• http://petrowiki.org/Production_logging