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doi:10.2204/iodp.proc.336.104.2012

Packer experiments

Drill string packer experiments were attempted in Hole U1382A with the intent of assessing the transmissivity and average permeability of the open-hole zone deeper than the casing shoe. The plan was to inflate the single-element packer centered at ~60 m into casing and then conduct two constant-rate injection tests of 1 h duration each. However, although the packer inflated properly, we were unable to maintain packer inflation, most likely owing to the effect of large swells (up to 3 m) produced by Tropical Storm Philippe. The packer has a single moving part, a sleeve that slides down ~25 cm after setting weight down from the rig to keep the packer inflated. This part has been reliable in past operations but is vulnerable to large swells that, if not perfectly compensated for, can pull the sleeve open and allow the pressurized fluids within the packer element to vent. This apparently occurred during four different attempts to set the packer at inflation pressures ranging from 1000 to 1500 psi and applied set-down weights of 10,000–15,000 lb (Fig. F49). Each time, the inflation held for roughly 10 min before unplanned deflation, which is barely enough time to register a borehole pressure reference, let alone conduct a useful test of formation hydrologic properties. After the fourth swell-induced deflation, we decided the swells were too much to handle and terminated the attempted packer experiments.

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