Meeting 16: 1 August 2016

Meeting Minutes

Date: 1 August 2016; 0900-1100 CST in C140

Attendees: Chieh Peng, Kara Bogus, Don Sims, Vinny Percuoco, Jason Sylvan, James Zhao, Algie Morgan, Lisa Brandt, Lorri Peters, Brad Julson, Denise Kulhanek, Leah Levay ; Via Zoom: Becky Robinson, Erik Moortgat, David Houpt, Rachael Gray

**Please feel free to provide feedback or ask for clarification on any item(s) below.

Welcome to new external/internal members

- Jason Sylvan (in person), Marguerite Godard (will attend next meeting)

Suggest Lisa Brandt become new technical lead

- No objections, so Chieh has tapped out!

Presentation/Updates

1. Introduction to Olympus Delta handheld XRF system (Vinny Percuoco)

· Arrived 1 August (1 day early from Olympus)

· Calibration is done externally – suggested once per expedition (is this too long a lag? Suggestions welcome.)

· Quantitative on homogenized discs; qualitative on core surface (same as previous device)

· Vinny writing up UserGuide – will distribute when ready

· Two techs trained on it per crew – XRD tech responsible for sample prep and thin section tech is secondary

· Should be ready before 366 –

· Chieh to check with Trevor on supplies

· Data exported as .csv file, opened in Excel and uploaded into spreadsheet – how to handle data storage – quantitative data stored in database

· Health and safety license (X-rays) –

· Brad Julson on top of it

· Kara uploaded ICP vs. XRF presentation from Jeff Ryan (Exp. 352) to Google site for reference (under Support Information/Documents)

2. Update on ICP analyzer application (Vinny)

· Current external software (ICPAnalyzer) has had complaints from sailing geochemists

· To address this, Vinny has created a new Excel-based procedure and demonstrated it at the meeting – it looks very promising and much more user-friendly

· He is currently working on a UserGuide and will distribute when completed

· Once this is done, he requests volunteers to mess around with data to try to work out any bugs or changes that need to be made to the program

· Suggestions for trials: Exp. 362 (technicians, NOT live program, no data storage), Exp. 363 (technicians, NOT live program) – EPMs on these expeditions (Katerina, Denise) are aware

· Anticipated live date: Exp 366 (December 2016)

· Data storage/archive to be the same as with the current program (ICP Analyzer)

3. Update on User Guides for the chemistry lab

· Lorri provided the list to Kara and it was uploaded to the Google site (User Guides & Tech Doc Status)

· David H. states there are newer guides, and will provide to Kara ASAP

4. Open action items

· Updated, current list: https://sites.google.com/a/scientific-ocean-drilling.org/lwg-geochemistry-mbio/action-items/open-action-items

· Please let Kara know if anything can be closed out!

Discussion items

5. Cruise evaluation review of 359, 360, 361

· Response to comments from Exp. 359:

· Precision from IC was disappointing

· Hamilton auto-diluter was purchased

· Lisa B. to check on Exp. 362 (Sumatra); along with ICP, see 361 below

· Consider shortening time for pH measurements (from 10 s) to limit degassing

· We will not change interval as this will introduce more error

· Response to comment from Exp. 360:

· Jason Sylvan gave a review of the plexiglass sampling enclosure used – recommends use on further expeditions featuring microbiology

· Kara uploaded image to Google Site for reference for any sailing microbiologists (Support Information/Documents)

· Response to comments from Exp. 361:

· General statement related to the preparedness/experience of sailing geochemists

· Example: major elements are measured with both IC and ICP but scientists, particularly if they are not pore water specialists, can be somewhat confused by this and may not be sure which data to trust more

· The LWG, EPMs and technical staff need to keep in mind sailing geochemists may not necessarily be familiar with the instruments/measurements performed on board, and thus need to be given quite a bit of background and need to be listened to/responded to sufficiently

· EPMs: It may also be worth distributing information specifically about the chemistry lab to the sailing geochemists ahead of time so they know what machines are out there and what measurements will be made (if you don't do this already)

· The techs are responsible for checking the precision of the machine, not whether the resulting values make scientific sense. However, they can provide input in terms of what has been done on previous cruises and/or what they have noticed is usual. Taking again the example of IC vs. ICP, they can say most major element concentrations used are from IC with the exception of Na, which is more reliable on ICP, but recommend that the scientists check previous IODP volumes and/or email the LWG.

· Issues with coulometer software

· Revision of the software is planned

· Phosphate analysis issues (UV-vis spectrophotometer)

· Autosampler installation is planned and should reduce replication errors in the future

· Blanks will also be run more frequently

· Sulfur (S) is difficult to analyze on EA

· This has come up more frequently (e.g., 354, 355). We have the capability to switch between CN and CNS columns to maximize either C & N, or S. Generally, when sailing geochemists are asked if they would like S measurements, the answer is, not surprisingly, yes. However, in many settings, obtaining robust S data is difficult (low concentrations), which sets the science party up for disappointment. Thus, the LWG recommends the following:

· S measurements should be seen as an exception, not a rule and should be requested in the cruise planning stages so we can organize to have the proper columns available. Unless concentrations are quite high, it is very difficult to resolve S and compromises C and N data somewhat to do so.

· This trade-off should be made clear to sailing geochemists before the cruise. If S is not desired, a CN column should be used during the expedition.

· Large offset between the IC and ICP data

· While some offset is unavoidable because they are different analytical techniques (and scientists need to decide which is more trustworthy – see example above), Lisa B. is going to check this offset on Sumatra (Exp. 362) and compare to other recent cruises

6. Do we need a current chemistry/microbiology “capability” document for internal use (to be available on the Google Site)?

· The idea behind this is that IODP staff would have a “go-to” place to see our current capabilities, recommendations, suggestions for the geochemistry lab that they can use to answer questions from scientists

· Examples of information: microbiology sampling (see plexiglass enclosure photo above!), microbiology contamination testing options, organic biomarker analysis, reality of measuring S on EA (it’s tough!).

· Lorri to sketch out and present at future LWG meeting

· Please let Kara know of any suggestions/comments for this

· Will be stored under Support Information/Documents

Technical points

7. IW report on LORE – 2 issues

· a. Sample type not visible – squeeze-cake (SQ) or rhizon – only listed at the very beginning, as the parent. See Exp. 349 data for examples

· So, all of the splits are always labeled e.g., IW_IC, IW_ICP, which does not indicate if it came from SQ or rhizon

· Need to find a way to carry that parent character

· Rhizon is from a section, SQ is from a WRND (can tell from sampling interval, etc. which could be which, but it’s difficult and not user-friendly)

· Short-term solution: Technicians need to indicate in sample ID whether it’s a SQ or rhizon – have this appear on standard report (understand this is annoying because everything will be on different lines), but to change LORE is not trivial and requires a project

· Long-term solution: Recommend a project to carry over parent ID info in LORE. Lisa B. to develop.

· b. Report modified – download whole table without

8. End of year purchases

· Ti squeezer? - No

· Spex X-press? - Yes

· -86°C freezer (one only goes down to -70°C?)? – Yes, today (1 August)

· Scintillation counter? – Ask Jason for specs?

9. Details for overall lab maintenance document (see additional attached file)

· Request comments to be provided via email to Lisa B.