LABORATORY ACTIVITIES

Chemistry Lab
While support for the leg science was fairly routine, considerable trouble was encountered with special projects and preparing the lab for the coming leg. After the CNS oxygen bottle was changed, double nitrogen peaks were noted. After changing more oxygen cylinders and rebuilding a leaky autosampler it was determined that the UltraPure oxygen was contaminated. Logistics personnel were informed.

While trying to improve the reproducability of the Dionex 100 anion values, the computer supporting it failed. This hampered the preparation of a new digital Dionex 120 unit that was to be used during the next leg. Problems with the computer, software, and networks cards for the new unit are being worked on. The Dionex 100 anion values were improved.

Erik Moortgat, the physical properties lab specialist, was trained in and supported the chemistry lab routine.

Computer Services
As we sailed, network availability was lost throughout the bridge deck. Initially the blame was focused on a new version of the Winfrog navigation system but the fault was finally traced to jerked wires in the radio room, a consequence of the Marisat-B installation. This effort also illuminated the fact that the network wiring labels were gone or had never been put in place when the wires were run. This problem was corrected. Later in the cruise, one small logging file was apparently sent successfully via the Marisat-B transmitter.

Network, server, and CC:mail support consumed a good part of the specialists' time. While things worked well for many, there were a few troublesome areas.

This was a Macintosh computer preference leg and three major difficulties hampered these users. Some could not save Microsoft programs to a server, others were Canvas users who needed/preferred different incompatible versions and, finally, there was network or backup software that subtlety corrupted the Macontosh programs available on the servers.

Corruption in the VAX camp took several days to overcome and reminded everyone how vulnerable the MATMAN and shipping programs are. The effort to transfer these programs to FoxPro is scheduled to continue during the next leg.

Two of the projects initiated this leg included sorting out the many PCs and Macs that are going out of warranty and putting them on the DEC service contract, and preparing some shipboard HELP files for inclusion on the local WEB page.

Core Lab
High-resolution sampling using the multisensor track (MST) and the Oregon State University split-core analysis track (OSU-SCAT) resulted in occasional backlogs of twenties of cores. It was sometimes necessary to switch logging to cores from a different hole (out of order logging) to allow real-time correlation control and optimized coring depth offsets for the construction of composite sections. The OSU-SCAT was located on the outboard wall of the core lab, reducing the table space available for the science staff.

The high incidence of liner failure made core processing on the catwalk more tedious and time consuming.

Heavy-duty bar-code and label printers replaced lighter duty models that were prone to break printing ribbons. The printer locations were modified somewhat to accommodate the significantly larger size of the printer.

Curation
An objective of this leg was to generate a plan for deferred high-resolution sampling, based on the shipboard physical measurements. This plan made use of composite records from multiple holes at each site and of the results of processing the shipboard paleontology samples. Work on the plans and strategy continued until docking. Guidance will be in place before the sampling in Germany takes place.

For reasons yet unclear, there was a 47% rate of failure in the core liners used during this cruise, from a few holes or dents to complete fractal fracturing. This resulted in extra time on the catwalk repairing the damaged sections and exhausted the supply of patching material. Soupy sediments in the top sections complicated this issue.

The 606 boxes of cores collected during this leg will be transported to the Bremen Repository.
Downhole Tools Support
The Adara temperature tools was deployed 24 times with 22 good runs. The Davis-Villiger temperature probe (DVTP) was deployed three times and returned good data on each occasion. Quality of the data was hampered by rough sea states during the measurements, but temperature gradients could be generated anyhow albeit with larger error margins than usual.

Electronics Support
The new hires became familiar with much of the equipment and helped diagnose and fix problems with the bridge-deck network wiring. Xerox service in Cape Town contributed to good service from both of the copiers.

Magnetics Lab
Problems with the Compumotor power supply interrupted data acqisition for a few hours in the middle of the leg. One Tensor toole failed and the second was impaired enough that no data were collected on one site.

Paleontology Lab
The Paleontology laboratory was heavily utilized during this leg by five paleontologists and a sedimentologist that used the lab to prepare XRD samples. Supplies were adequate and few problems were mentioned. The 21K Marathon centrifuge will be returned for repair. The sieve inventory was updated.

Physical Properties
The lab received reduced attention (few hours a day) by the lab specialist because he was being trained and helped in the chemistry lab as well. Several problems with data acquisition (P-wave logger [PWL], P-wave on split cores [PWS3], natural gamma ray [NGR]) and data upload (NGR, moisture and density [MAD], PWS3] were noticed by the scientists, sometimes quite late when they were writing their reports. Some of the problems could be fixed ad-hoc while others remain for Leg 178.

Control measurements are still not measured (for the MST) and/or uploaded (for MAD) on a routine basis. This makes it hard to identify problems early and impossible to correct data later.

The OSU-SCAT produced the bulk of the diffuse reflectance data on this leg, and also acquired resistivity data using Wenner-type probes inserted ~1-2 mm into the core. The Minolta CM-2002 photospectrometer was mainly used for XCB cores where "blind sampling" with automated sampling increments does not produce reliable data, or when the SCAT could not keep up.

The SCAT was a bit slow because the motion control was not optimized for ODP cores and the time crunch on ODP legs. The distance the instrument is traveling up and down could be reduced to ~20% and logging would be at least twice as fast (sampling twice as dense).

Underway/Fantail
WinFrog version 2.60 navigation software was installed during the port call with the annotation changes expected. A review done during the initial transit resulted in a critique that was sent to the Pelagos programmer. A revision is expected for the coming port call.

A new Ashtech GPS/GLONASS receiver was installed during port call; the original unit was installed in DP to provide an independent positioning option should the network or beacons fail at the same time. The increased accuracy of the combined positions may contribute to a margin of safety.

X-Ray Lab
Nearly 400 samples were submitted for XRD bulk analysis. Eight standards provided by a shipboard scientist were also analyzed so that quantitative analysis of opal concentration in the samples could be done onboard. Many of the samples were treated with HCL by a shipboard scientist, who did the drying and grinding as well. The opal standards and a new shareware version of MacDiff (3.0.0) were left for us to use on future legs.

The unit was out of service during one week while a series of problems with the detector, the generator wiring, and the system controller card were diagnosed and repaired.




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