SITE 858



Hole 858G

A Datasonics 354M retrievable commandable beacon (208 dB) was dropped at 2115 hr on 22 August on the dGPS coordinates for Hole 858G: Latitude 48°27.360'N, Longitude 128°42.531'W. A data logger retrieval BHA was run as follows: modified CORK running tool, pony drill collar, 2 X 8-1/4" drill collars (DC), tapered drill collar (TDC), 2 stands of 5-1/2" transition drill pipe, crossover (XO), and 5" drill pipe (DP). The BHA was positioned over Hole 858G at the given dGPS coordinates when the VIT-TV was run. The modified CORK running tool was jayed-in after numerous attempts by setting down a 15K lb weight and applying left hand torque. A 10K lb test-pull confirmed latch-in. The wireline fishing tool was run to retrieve the data logger. A 400 lb overpull was noted and it was assumed that the data logger released and was being retrieved at 2 m/min on the wireline. When the 400-m-long thermistor string would have been clear of the CORK, numerous unsuccessful attempts were made to unjay from the CORK. Something appeared to be preventing movement of the running tool. The ship was offset about 5 m in a circle around the site, and about 15K lb of weight were set down with right-hand torque to release the running tool. After unjaying, the ship was moved 20 m off the hole to retrieve the data logger overshot; however, it was empty and did not appear to have engaged the data logger. The running tool was pulled for inspection to determine why engagement and release were so difficult. The bottom end of the funnel was bent in two places (from setting down on ROV platform ribs?) and some brinelling was noted in the jay-slots, indicating that the running tool may have been tilted slightly relative to the CORK. The funnel was shortened by three inches, the jay slots were dressed, the skirt lip was beveled in the jay slot, the running tool was painted black to reduce glare from the TV lights, and the 75 W TV light was replaced with a 50 W bulb. The modified CORK running tool was run again; however, the seas had increased to 6-7 ft, heave was 1-2 m, the roll was erratic, and the weight indicator was varying by 20-30K lb. Although winds were only up to 17 kts on location, locally seas were in a confused state. The attempt to stab over the CORK was aborted and the tools were pulled out. The beacon was turned off and left in place for the return as soon as weather permitted.


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