JA Daily Science Report for Expedition 309, 17 July 2005

 

LOCATION: Site 1256

 

SCIENCE UPDATE: The drill string was raised to a depth of 4368 mbrf and the  WSTP was lowered into the drill string to obtain a water sample and temperature measurement at 724.6 mbsf (4369.6 mbrf). Upon return of the WSTP the water sample was found to be murky and a low salinity (26 per mil) indicated the filters had become clogged with silt before the sampler was completely purged of nanopure water. The WSTP temperature measurement gave a flat line temperature of 60 °C due to installation of the incorrect thermistor in the tool. It was decided to run the WSTP again to get a better water sample. While the WSTP was cleaned for its second run, the Adara tool was deployed to obtain accurate temperature readings above 60 °C. Temperature at 712.6 mbsf was 64.5 °C and at 724.6 mbsf was 65.8 °C. Our best estimate for temperature at the bottom of the hole is 68 °C. The second run of the WSTP, taken at 4357.6 mbrf, returned a better water sample. The drill string was raised to 3907 mbrf and preparations were made for logging. The Schlumberger logging tools were lowered into the drill string at 1200 hr on 17 July.