The offshore-A oil field is located in the Arabian Sea to the west of Mumbai India & is operated by ONGC under Asset based management system. The field is a saturated reservoir with three small gas caps & is under production with pressure maintenance by peripheral water injection. Some of the wells falling near to the gas cap produce with high GOR due to gas coning or cusping. Several efforts made to control the high gas production by conventional cement squeeze technique did not produce any result. As a result the wells were either closed or under production sub-optimally with a low choke size.

The low recovery from the area due to closure of the high GOR wells & unsuccessful attempt of cement squeeze jobs for Gas shut off warranted ONGC to search for new technology to control the high gas production with a deep penetration new gel technology.

Accordingly the gas control jobs were carried out in two wells after an extensive study on reservoir characteristics, selecting best candidate wells & right type of polymer gel, involving laboratory studies to see the compatibility of the gel with the core & formation fluids and using proper gel placement technique. This integrated approach with a multidisciplinary team effort was adopted for the first time under the asset based management system.

The post treatment production data showed significant reduction in total gas production along with substantial increase in oil production which indicates that the gas production from the gas cap has been blocked successfully by this treatment.

The paper deals in detail the integrated team approach adopted in the Asset team for a reservoir focussed conformance solution to improve the recovery which led to a success and has opened up a new era in the gel technology for gas shut off in carbonate reservoirs in Indian offshore fields.

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