Technician: Ty Cobb 

Summary

Expedition 383 was a moderate recovery Expedition; samples run in the X-Ray lab were predominantly clay samples. No Zi correction factor was need for the D4 after the QAQC run at the beginning of the expedition. The Bead Maker ran without issue, it was serviced and the rotation block cleaned. It is highly recommended that the Bead Maker not be run during transits.

The high storage shelf was extended to allow for 2 rows of flux vials to be placed in the space, freeing up the shelf under the user station. The two computers were attached to the cabinets off the floor and to free up space under the forward bench top. The oven was placed under the forward bench top in preparation for the new instrument arrival. The spare XRD computer was place on the high storage shelf.

A D4 service call is scheduled for the San Diego port call (1st or 2nd is unclear), they will replace the x-ray tube and do a full preventative maintenance check. Malvern Panalytical will be delivering the benchtop AERIS to the first San Diego port call. The delivery is scheduled for 3 days, the first day is meant to be for instrument install and the two remaining days are intended to train the technical staff on board.

Totals

XRD SAMPLES: 141 Clay; 2 Bulk
XRD TEST: 455 Clay; 2 Bulk
ICP: 141
XRF: 283

XRD

The D4 ran without issue for the extent of the expedition. The instrument was opened and cleaned upon arrival into Punta Arenas.

There was a suspected contamination issue within the D4 after the end of the previous Expedition, the following method was used to determine that was no issues with the instrument:

• Testing using blank zero background disc - suspect results only from 3.5 - 40 (10 runs) show a peak (hump) at 37-40, when the same is run from 3.5-70 (10 runs) the peak is not observed

• Cleaning of the sample spinner using air and non silicon lubricant has seemed to help, there appears to be a lot of material in the spinner bearings.

• Inside the instrument was extremely dirty, what is thought to be pyrite was found on most surfaces. In a set of 10 runs the instrument was cleaned after each run.

• Further testing, running a background disc loaded with our calcite standard continuously for 10 runs, shows minimal impact.

• Ran old zero background disc, no peak seen at 37-40 for 20 runs continuously without cleaning the instrument. After there was minimal residue found, meaning that cleaning may have alleviated one of the problems, no change in data was observed.

• The new zero background disc (Disc 1) was placed in the furnace at 550C for 1 hour, then ran once specifically looking to see if the peak at 37-40 remains, there was an obvious drop in counts.

• All 7 new background disc were run once, and then placed in the furnace at 500C for 1 hour. Disc 1 which has been through the furnace once already is being processed again. There is no change across the seven disc. The only one that shows a different diffractogram is disc1 with no change in the second run.

• There is no obvious change in the 7 disc after running them through the furnace. Disc 1 which was put through twice had no drop the second time it was run.

To make sure there was no issue with the silica disc, Bruker was contacted and they responded to this issue by saying that the zero background disc are not meant to be run empty.

The runs of the Corundum standard from numerous Expeditions were compiled and showed decay of the x-ray tube is at 70% although no Zn correction was needed, Bruker recommends replacement at 50%. A service call has been scheduled for the San Diego port call.

Software

On the D4 host computer, the .EVA software was giving an issue when printing, where it would only print on a small portion of the page. Bruker did a WebEx session during port call and was not able to solve the issue, they offered to send out a new version of the software to fix the issue. Once, the new software was installed the printing issue went away. However, the software is not optimized for 4K monitors and is slightly jumbled in sections, it does not effect usage only the view.

HASKRIS

The Haskris ran without issue. The flow rate on July 17th was 6.85. The filter was cleaned at the beginning of the expedition. The water was changed on May 26, 2019.

Freeze dryer

The Freeze dryer ran without issue. Please note: In Auto mode there is no need to turn on the vacuum; the instrument will automatically do this. If the vacuum pump is manually turned on while using Auto there is a chance for water to get to the vacuum pump.

Vacuum Pump

The vacuum was serviced, oil and filter were changed on June 7th, 2019. The oil was very dirty and had not been changed for a while.

ICP

Shatterbox/Mixer Mills

The Shatterbox ran without issue this Expedition. The Mixer Mill was not used.

Beadmaker

The Beadmaker had no issues. During transit with heavy seas, the extreme flux in the power to the bead maker caused an unknown electrical noise to occur during running. As there have been several problems with power in the past, we decided to turn off the bead maker and wait until we were more stable. After arrival on site, the bead maker was turned on and no noise was observed and the machine ran without issue. It is recommended that the machine stay off during times where the power may flux in extremes.

After discussion with the vendor, the machine was serviced and the rotation block was cleaned. The instructions on how to do this are on the confluence tech manual page. The gold fitting that sits between the rotary and the base had a lot of corrosion, which was causing a loud high pitched sound to be emitted when the agitation step was being performed. Removing the corrosion, alleviated the sound. Also, the 2 quartz pads that sit under the glass in the sample holder where worn down to crumbs. New pads were put in, but a decrease in temperature of the sample was observed and when running blank flux. The sample had to be heated to 1150 in order for it to completely melt. The vendor was contacted and had the following response:

Response from Vendor - They suggested not to use quartz pads at all. Removing the quartz pads, a sample was able to run the normal method at 1050 with no issue.
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Hello Ty Cobb


Regarding to the quartz pads, we had recommended to use this only alkali 
fusion for ICP-MS purpose. But now we don't recommended at all for any
application, any customers.

And we are not sure this affect to the performance of heating system, 
but we recommend to not use this quartz pad.

By those reasons, we don't have any stock in our yard.

Anyway we are really happy, sharing information about our product seems
to be contributing your research activities in somewhere on this globe...

BR.

Shirota
Amenatech

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XRF

The pXRF was used for half-section measurements. The scientists asked that the data be exported in percentage instead of ppm. The units are officially (will remain) off the LORE report. The pXRF expanded report is now functioning properly, the LWG has been asked to review the reported columns and decide what should be included/excluded from the report.

User guides

The SOP and all user guides were reviewed and updated as needed during the Expedition. All documents are up to date.