399 X-Ray Technical Report

Summary

Expedition 399 Building blocks of life, Atlantis Massif, occurred in Ponta Delgada, Azores. The expedition lasted from April 12th to June 13 of 2023. We drilled a total of 2 sites for the extent of the expedition recovering hard rock on both sites. The samples processed in the X-Ray lab where as follows:

• ICP samples taken form working core where analyzed for both XRD and pXRF powdered samples

• MBIO samples taken from the whole round where analyzed for ICP and XRD

• Some XRD samples where taken directly from the cores. 

The material recovered was more than what was expected, we had many samples and with that a lot of the supplies where finished or left at a restock level. The materials that we are low on are weighed flux vials, and empty vials for ICP samples. The recovery of peridotites presented certain challenges when chrysotile was found in the cores. Samples for XRD analysis were reduced because of powdering dangers, and only MBIO ICP samples where allowed to be processed in a safe enclosure. The scientists volunteered to do this processing of samples and the X-Ray technician processed the samples that where gabbro as usual in the lab. 

Sample Totals

METTLER TOLEDO BALANCE

The balances were used to weigh LOI and Flux for the chemistry lab. In order to weigh flux correctly it was measured within this limits 0.3997 to 0.4003. The balances are also being used by the chemistry technicians, since their balance broke during this expedition. 

BEADMAKER

The beadmaker bead quality improved with the polishing of the crucibles. Many beads where left intact upon drying without breaking, if possible it is suggested that the most recently polished crucibles are used over the older ones. All of the crucibles where used due to the high amount of samples collected during this expedition. 

LABCONCO FREEZE DRYER

The oil from the vacuum pump was serviced during expedition 399 on 6/6/2023.

AERIS XRD

The AERIS was used for the XRD, it was serviced during the transit and the only re-occurring problem was the motion control  arm when restarting the machine. 

Midway through the expedition the DI water had to be refilled because it was running low (Figure 2). The screw in the fill plug was tightened so much that it was very hard to take out. When I tried to remove the screw it would roll the halo surrounding it making it impossible to remove (Figure 1). In order to remove this screw it required two technicians one to hold the surrounding halo and the other one to turn the screw. It is suggested that the screw is not tightened at all it just need to be in place to protect the water. 

Open

Open

Since, the water was running low on the AERIS and the machine was getting warm I made the decision to turn off the machine until we could refill the water. After turning the machine back on the motion control error in the arm re-appeared, the arm was gently moved into place and a sample was loaded into the machine. The computer screen froze and nothing could be done after that, not even turn off the machine. Therefore, the AERIS had to be unplugged in order to restart it and after that the machine resumed its normal operation. 

ICP Prep

In this expedition we had a sample total of 263 ICP requested both from MBIO and from the working cores.

Flux Weighing

Due to the high amount of samples we ran out of several supplies for processing ICP samples, these include: weighed flux and vials. In order to process all of the samples Lithium Metaborate found in the X-Ray safe locker had to be weighed and placed in MAD station vials.

The process of weighing the flux was as follows:

1. Tare the Mettler Toledo balances, putting a weighing paper on each balance, to 1000 counts. 

2. Add the Lithium Metaborate for weighing 

3. The weight goal had to fall between 0.3997 and 0.4003

4. After the goal weight is reached place the lithium metaborate in a vial.

Crushing Samples

In the beginning of the expedition crushates of ICP samples where requested as a pool sample. The rocks were hard to crush in the x-press to the desired grain size of the scientist and it was very hard to crush to with a hammer, so the Jaw Crusher was used for ICP prep during this expedition. The ET checked the Jaw Crusher to make sure it was functioning properly before using it with the samples. The Jaw Crusher is more effective at crushing rocks than the X-Press, so it will be left in the surface of the ICP prep area. It can crush the samples to a smaller grain size than the x-press and after that the sample can go into the shatterbox. The Jaw Crusher should be properly cleaned with isopropyl between each sample on the inside where it crushes the sample as well as the tray where the sample falls into. 

Sample Processing

Sample processing in the x-ray lab was done by X-Ray Technician and Scientists. The chemistry scientist was processing her samples that contained chrysotile in the paleo lab's enclosure, while I processed the gabbro, norite, troctolite, diabase, basalt, and diorite samples. This was done for powdering and making beads as well. Beadmaking for the chrysotile samples was done by two scientists. It was noted that three of the crucibles had bent edges on one side, but they are still usable (Figure 3). One of the crucibles seems to have been hit very hard from underneath to get the bead out and the bottom was bent, I would say this crucible preferably won't be used anymore as it would not do a good job mixing the beads (Figure 4 and 5).

Shatterbox

The new shatterbox was relocated to the Paleo Prep Lab, where the enclosure for powdering chrysotile was located. In order to make sure the samples would not leak powder the ET made some gaskets to fit the tungsten carbide containers. After the specialized cleaning crew come to clean the labs the shatterbox can be returned to its original location. 

Bruker Tracer 5 Handheld pXRF

A first draft of the pXRF track was created during this expedition to measure sections of hard rock. The track was placed underneath the TV was seen in Figure 6. The gun can be easily moved between its two setting the benchtop stand and the track. The track is easily used and it has a ruler on the side where you can measure your offset in the core. The gun slides through the section and once you decide on where you want to measure you can lower the gun using the red button (Figure 7). It was observed during this expedition that the preference for the scientists is usually to use the benchtop stand and place the hard-rock pieces in there. Regardless, using the track or the benchtop stand will be up to the scientist preference, so they should both be set up for them to use. 

Bruker data uploader works well although it had issues during the expedition. MUT would be extremely slow making it really hard to check the data because it would not respond every time you tried to click something in the program. The developer reinstalled the program several times and after doing so the settings for the uploader had to be re-adjusted (Figure 8). After analyzing the issue the developer concluded that the issue occurred when trying to open excel at the same time that MUT was reading the files.