Downhole Measurements Laboratory
The Adara, Water Sampler and Temperature Probe (WSTP), and Los Alamos water sampler were operated by ODP personnel. Extreme hot water (>200°C) conditions constrained deployment of the WSTP and Adara. Confirmation that downhole conditions did not exceed 150°C and 100°C, for the WSTP and Adara respectively, was required before deployment in hydrothermally active holes. In holes with water temperatures exceeding these limitations the Los Alamos high temperature water sampler was used, but met with only minor success because of its aged O-rings and poor design. Technicians assisted the shipboard loggers with thermistor string deployments at the two CORK sites.
Activities in the core laboratory were normal for a hard rock leg except for the special handling of the sulfide cores. H2S monitors where installed on the catwalk, core locker, and air intake for the ship's house and hand held monitors were used as necessary. Although, this leg was identified a potential "H2S leg", no other H2S safety precautions (rig floor monitors, wind socks, classes, or drills) were taken by the ODP Drilling Operations Manager. The ship's crew completed a few maintenance projects on the core stack, nevertheless, the whole lab stack is rapidly deteriorating because of neglect at the last dry dock and the lack of a serious maintenance effort since.
Massive sulfides, borehole water samples and mineralized CORKs provided many curatorial challenges.
The new 2G magnetometer hardware functioned very well but the lack of adequate software was a problem. However, the newly written ODP labview software, CRYO, rectified this deficiency making the system adequate for shipboard needs.
In addition to the normal science support activities, a number of special projects were completed during the leg. These projects included 1) software upgrades for MST, VS, and MAD, 2) completion and verification of the JANUS upload software for the MST, VS, and MAD data, 3) evaluation of the GEOTEK Multi-Sensor Split Core Logger, and 4) installation of the new MST track.
Along with high resolution in situ water samples, open borehole samples of hydrothermal fluids were analyzed. Geochemists handled most of the wet chemistry analyses such as calcium, magnesium, and chloride titrations, spectrophotometer tests for boron, silicate, and NH4. They also handled the AAS analysis for Li, Sr, Zn, Pb, and Mn. The Dionex was utilized to run for anions and cations.
At the hydrothermal sites, heavy hydrocarbons were commonly encountered. Aromatic (benzene - toluene) and some other carcinogenic compounds were found in the samples. The cores containing potential health hazards were identified and marked. However the levels of these compounds were found to be very low, unless they were concentrated in tar balls.
Thin Section Laboratory
The thin section laboratory received only moderate use with the lithology types evenly distributed between basalts, sediments, and sulfides. The table top under the Logitech and Petrothin equipment was replaced.
Over 130 samples were analyzed by X-ray diffraction (XRD) on Leg 169. After a brief teaching session, scientist Damon Teagle prepared and ran virtually all of these samples throughout the leg. Approximately 40 samples were glycolated (designated with a `G' suffix) to help identify various sheet silicates and the rest were prepared as simple bulk mineral smear-slides. The results were used only for mineral identification and a wide variety of silicate and sulfide minerals were determined using the ODP-1 XRD pattern database.
The X-ray fluorescence spectrometer (XRF) was completely recalibrated for major and trace elements following a service call during the Victoria, BC portcall. The calibration took much longer than usual (3-4 weeks!) because of the need to sort-out the ARL software, and several elements required more than one calibration. Once running, the XRF worked very well analyzing 31+ samples for major and trace elements.
During this leg the preproduction testing of the JANUS system continued, with the goals of identifying problems and allowing the marine technicians to gain experience using the system. We entered all corelog data and the necessary operations data needed to support corelog. We also tested the sample application, although not all sample data for this leg were entered into JANUS. At the start of Leg 169S we rebuilt the Oracle database used with JANUS and at that time it was configured for the production environment. We used this leg to complete the transition of the shipboard Unix environment to follow closely the shore environment. This included completing the upgrade of the general purpose SUN work stations to Solaris 2.5. Splicer was upgraded to a Solaris version with minimum testing.
The laboratory equipment operated satisfactorily during the leg. No major problems occurred with the majority of the equipment that were out of the ordinary, compared to past leg experiences. As always the first two weeks were spent addressing minor problems that were discovered during start-up operations and setting up equipment to fit the personal needs and preferences of the laboratory scientists and technicians.
This was a low core recovery leg. There were, however, a large amount of close-up requests at Site 1035. Also, there were requests for photos of CORK operations and special events.
Underway Geophysics Laboratory
Navigation, bathymetry, magnetics, and seismic data were collected during Leg 169. The site locations were well surveyed from previous expeditions. All beacons were dropped on predetermined coordinates. A short seismic survey was done during the approach to Site 1037 and again on the transit to Los Angeles to test a new multichannel streamer. Both tests were successful. Hole positions were determined by averaging differential GPS fixes taken at a one minute interval over a period of several hours for each hole.
The 80" water gun was deployed to test the 6 channel seismic system. Otherwise, fantail maintenance projects were minimal.
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