METHOD OF WELL OPERATION Russian patent published in 2004 - IPC

FIELD: oil industry, particularly for determining damaged areas inside casing pipe and for detecting cross-flows in annulus space.

SUBSTANCE: method involves performing current gamma-ray logging and carrying out control gamma-ray logging with the use of radioactive rock elements as radioisotopes; comparing current and control gamma-ray loggings by superposing next and previous gamma-ray logging curves; drawing curve demonstrating difference between gamma unit values of next and previous curves; taking maximal difference between gamma unit values change as 100%; determining dynamics and percentage change of gamma unit values in well areas; determining damaged areas and repairing the damaged areas. When determining casing pipe damaged areas above liquid level into well damage is detected in dry part by initial changing difference between gamma unit values. Source of water entering in annulus space is detected by end of above curve change. Indicator of casing pipe damage corresponds to difference between gamma unit values of 80-100% and absence of dynamics and rapid change of gamma-ray logging characteristics. When indicating casing pipe damage below liquid level the damage is determined by beginning in change of curve demonstrating difference between gamma unit values of next and previous curves of gamma-ray logging. Indicator of casing pipe damage corresponds to difference between above gamma unit values of 5-60%. Absence of dynamics and rapid change of gamma-ray logging characteristics, interval of annulus cross-flows is determined together with temperature logging by changing temperature of damaged area and by smoothing of temperature curve.

EFFECT: increased simplicity, improved accuracy.

2 cl, 3 ex