by Jessica Riekenberg

Summary

During Expedition 397, the Bruker D4 XRD was used to analyze all sediment samples. Sediment (unignited) was weighed out from each XRD sample to make beads for ICP analysis. The Bruker Tracer 5 pXRF was used for high resolution measurements of a depth interval of interest at site U1587B, Cores 1 and 5-7. A new safety presentation and an updated safety guide were completed for pXRF operations with the new device. The full user guide and a quick start guide have been started and drafted, respectively, for the Tracer pXRF. A remote in to the Bruker Tracer 5 pXRF was completed, restoring the missing application and fixing one of the results files produced by the Limestone application. The uploading of pXRF data was configured by the Developers and successfully completed. The Labconco freeze dryer was delivered without the bell, so installation is on hold until that arrives at the Exp 398 port call. Otherwise, all instruments are in working order at close of expedition.

Sample Totals

Instrument Updates

Bruker Tracer pXRF

The Tracer was received toward the end of port call in Lisbon. The device was checked and found to be operating properly. A few days of being powered on and plugged in recharged the internal battery and the date and time were reset. A ship laptop was set up for the Tracer that will allow server access without a hard wire connection. Scientist should sign in with their own login to the OES to be able to download and save data to Uservol. This information has been included in the Quick Start and User Guides for the Tracer pXRF. The shore laptop that was sent out with the Tracer has been given to the MCSs to store in Lower Tween. It still works with the device and can serve as a backup.

The EPM and scientist requested to use the Tracer to measure several section halves of a core with areas of interest during the second site. A quick start guide for the scientists was drafted and a brief presentation on operating the device was presented to the scientist performing the measurements. The Tracer was used with the desktop stand and lowered onto the section half, which was covered in Ultralene (Fig. 1). Moving the device up and down on the attachment rail was found to be challenging and not smooth. A plastic holder that the device could be set in during measurement was prototyped and 3D printed (Fig. 2). This provided a stable means of measuring on section halves while also incorporating more shielding for the device during measurement (although this is not required by the manufacturer). This holder addresses the concerns of the scientists on Exp 393 who found it difficult to hold the device on a section half and measure. The holder opening allows the nose of the device to stick out underneath by several millimeters (Fig. 3), which should allow the device to be able to sit flat against the sample surface. If the sides of the core liner are too high, which could happen with hard rock core liners, use the putty to prop the piece up in the liner. Subsequently, because the nose sticks out, the Tracer needs to be taken out of the holder before moving to the next area of interest - do not slide the holder with the Tracer in it along the section half! This could damage the measurement window and/or the surface of a sediment core. To aid with this, a stand to hold the Tracer in between measurements was made from the initial shielded holder prototype (Fig 4). Feet were added and this became a stable dock that the Tracer can be taken in and out of quickly. Additionally, special section half holders were also 3D printed that can hold a ruler next to the section half for easy reference when measuring (Fig. 5). These holders can be used with the printed box holder and a ruler (Fig. 2, Photos 1 and 4).

Open

Open

During this time, leak testing was performed with the ion chamber to determine the level of scattered radiation occurring during the measurement of section halves. The radiation profile provided for our pXRF (Fig. 6) from Bruker indicates the highest amount of scatter is detected at points H and I, perpendicular out to the side of the nose of the Tracer. When used pointed away from the operator, this is not a concern. However, as we use it when measuring on a section half, this scatter is in a direction toward the operator. The Bruker measurements are done at a distance of 10 cm. We performed measurements at multiple distances, with and without the shielded holder (Table 1). Shielding is not required by the manufacturer, but additional shielding within the holder decreased scatter to only slightly above background at less than 10 cm and by 20 cm, there is only background radiation levels detected. This helps decrease scatter for the operator and any potential unintended bystanders, depending on the location the Tracer is set up. 

With the Tracer being fairly new onboard, it was prudent to update the safety presentation and the safety guide with the safety features of the Tracer. This also seemed a good time to refresh the safety presentation and guide with up-to-date information on regulation dose levels and general information on radiation and radiation safety. These have been drafted and await review. 

The Quick Start Guide provided the scientists will need editing and additional information. 

The full User Guide has been started and will need to go through quite a bit of editing as we move forward and agree on how all aspects of sample preparation, measuring, and data management are to be handled. Some very important issues to cover are:

• Clearing the internal memory, potentially after each site, or when we get to a specific run number.

• Also keeping the USB clear. The vendor has indicated that a lot of data files on the USB in the Data folder contributes to the device freezing up. Therefore, the data should be removed from the USB to a separate folder on the laptop or copied to data1 before deleting off the USB.

• The trained operators should use the User password, not supervisor password. They can still download the data as a User, but they do not need access to some of the other functions available with the Supervisor password.

• ALL the data files should be downloaded to the Data IN folder before the data is copied elsewhere.

• The barcode scanner has been programmed to scan the TextID, which can be used when editing the sample information. The JR6 rules were used, which sends everything up to the comma, so it works for both 11 or 12 digit TextIDs.

• The run numbers do not have to be automatically reset when the internal memory is deleted. For the option 'Reset Assay file name counter' (Fig. 7), making sure this box is not checked, will allow the run numbers to continue after the internal memory is deleted. 

When working with the Tracer to start the user guides, it was discovered that the Mudrock (Air) application had not been reinstalled when the device was in Germany for repair this past September. Additionally, when testing the Limestone check sample, it was discovered that the Limestone.tsv results file was missing the reporting of values for CaCO3. A product specialist with Bruker was able to fix these issues during a TeamViewer session with the Tracer connected to the XRDIH computer. The Bruker pXRF software was installed on the XRDIH computer to accomplish this and can be utilized in the future if needed.  The specialist copied the Mudrock (Air) application files to the device and corrected the script of the Limestone.tsv file. Both of these were tested during the TeamViewer session and seemed to be operating properly. 

One further issue was that the Limestone application check sample values were out of tolerance based on the ranges provided by Bruker in the calibration certificate for the Limestone application. A set of 10 measurements were performed and all results files sent to Rick at US Analytical to consult with Bruker. The product specialist at Bruker, Dayeeta, says everything looks fine and she changed the calibration values for our instrument and sent a new calibration certificate for the Limestone application. 

There is an issue with the proximity sensor, so at times it will stop a measurement for no apparent reason, prevent a measurement from executing, or it would indicate something was in the measurement window when it was still several inches away. Communication with Rick at US Analytical indicates that something may be loose with the sensor. He suggested disabling the proximity sensor if this becomes too frequent. The backscatter sensor is still in place, which will terminate the measurement if no backscatter is detected (if the device is pulled away from the sample mid measurement) and this feature cannot be disabled. This should be addressed if the Tracer is sent in for repair again, but is not an issue that prevents measurement (because it can be disabled while there are still other safety features in place that cannot be disabled) or affects data quality.

Working with Developer Tim, the data for this expedition was able to be uploaded in a format similar to the previous device. MegaUploadatron2 (MUT2) utilizes the '.tsv' files produced to upload the element % weight  results for each sample. Each sample also has a '.pdz' spectra files and the 'Results.csv' uploaded with it. Details of the upload procedure are outlined in the full User Guide for the Tracer.

Bruker D4 XRD

The Bruker was used to analyze all XRD samples for this expedition. Samples were initially taken at a resolution of 2 per core at the first site (U1586A). All subsequent sites were sampled at 1 XRD sample per core (U1587A, B, and C, U1385F, and U1588A). The Bruker D4 XRD was used to analyze the XRD samples.  The first site scan parameters were 5-70° 2θ, 0.008° step, 0.22 s/step (30 min), then changed to 4-70° 2θ, 0.008° step, 0.40 s/step (56 min) for all remaining sites. This change helped decrease the signal to noise ratio for analysis of minor element. The bolts of the sample table cover were found to be loose on the left side and with ET Garrick's assistance, both sides were checked and tightened. Additionally, preventative maintenance was performed as indicated in the maintenance schedule. The instrument worked without issue for all samples.

Haskris

Preventative maintenance was performed on the Haskris as indicated in the maintenance schedule, including changing the water and cleaning the filter. The flow rate was documented as 6.32 L/min after the maintenance. The Haskris worked without issue during the expedition.

Aeris XRD

Daily checks were analyzed on the Aeris, however, no samples were analyzed. Preventative maintenance was performed as indicated in the maintenance schedule, namely cleaning of the fan filters. One system error occurred, but was cleared by powering the instrument off and on again. It is important to refill the reservoir on a routine basis (once a month!). There were errors in the Error Log indicating the instrument had reached high temperatures and when investigated, the coolant reservoir was found to be below the 'Low' level. This was refilled and checked routinely and the error did not reoccur. Otherwise, the instrument worked without issue the remainder of the expedition.

Beadmaker

The beadmaker was used to make 247 beads for ICP analysis and operated without issue for the duration of usage. As indicated in the maintenance schedule, the water filter of the beadmaker was changed at the end of the expedition. Thirteen crucibles were sent off for recasting, while ten remained onboard and were well used during the expedition. The water filter was changed as it was overdue for being replaced.

Software Updates

New license for the PDF-4/Axiom mineral database (2023) were received digitally in early October and installed on the virtual computer and XRD Instrument Host (XRDIH). These license are good for 3 years (until the end of September 2025). A third license was also purchased and installed onshore. A copy of the database has been saved at V:\TAS\dml\software\labsystems\XRD Software\Databases Phase identification\ICDD PDF-4-Axiom 2023 Database.

A program for XRD file conversion, PowDLL v2.9, was installed on XRDIH to facilitate converting XRD scans between files types for scientists who use programs other than DIFFRAC.Eva and HighScore Plus.

The Bruker pXRF software programs, Bruker RemoteCtrl and Instrument Tools, were installed on the XRDIH computer to facilitate the TeamViewer session with Bruker. The Tracer can now be connected to that computer and use Bruker RemoteCtrl and Instrument Tools. This can be utilized in the future if a remote session is needed or to manage/delete data files when needed.

Lab Updates

XRD Lab Notebook instrument pages were updated, as well as the Preventative Maintenance schedule.

Because of the shortage of the16ml snap cap vials (LS0113), 8ml snap cap vials (LS0276) were used to store the XRD residues.

A kit for sampling vein material from hard rock cores was put together previously (Exp 393). This kit includes several fine tools (Fig. 8) and is stored in the 'Special Curation Tools' drawer in the splitting room.

Freight

Received

• Bruker Tracer 5 pXRF from repair in Germany

• Labconco Freeze Dryer main unit (Did not include bell)

• 4 Boxes of flux vials

Oncoming

• Bell for Labconco Freeze Dryer