REVERSE CEMENT SQUEEZING TECHNIQUE FOR LINER CEMENTING IN BURIED HILL RESERVOIR

Some severe lost circulation and sloughing accidents occurred usually during drilling in buried hill reservoir. To prevent these accidents from occurrence,the intermediate casing was run immediately before getting into the buried hill reservoir. Then it was forced to finish drilling through buried hill Interval. Finally liner was hanged to isolate the shale interval from intermediate casing shoe to the buried hill formation. During operation, reservoir formation was damaged seriously by lime milk plugging and liner cementing. This paper presents a reverse cement squeezing technique which sets the liner in the non major buried hill reservoir and then cements the liner utilizing the lost circulation in buried hill interval. It can meet the requirement of shale interval isolation as well as minimize formation damage by cement slurry during liner cementing.