See SOIREE Preliminary Voyage Report
Notes
A. CHN
1. Both silver and QMA samples were analysed by punching a sub-sample using a 4.16mm punch.
These were then acidified with 20ul of 50% HCl in silver cups, dried, reweighed to estimate
carbonate loss (squat-all) and combusted in our Carlo-Erba.
2. The number of punches taken for each sample varied according to how much material it had.
The spreadsheet calculates the umol C on the TOTAL filter based on the # of punches, punch
area and effective filtration area. To get the effective filtration area for a silver filter
I measured the diameter that material covered to be 22.88mm. For the QMA I took it to be 140mm.
3. For the 2 overloaded samples 41C and 105C, I (Trull) used the weight ratios to calculate
the total umol C that must have been on the filter. The tare of empty petri-dish with lid
and blank silver filter was 8.91639g. Estimating the total material weight by either using
Charette's initial weight and subtracting this tare, or using Trull's final weight (minus the
same tare) and adding back in your and my sub-aliquots agrees to better than 3mg (105C) and
1.5mg (41C) in comparison to ~400mg totals, suggesting errors of under 1% from the tare correction.
4. Measured QMA and Silver filter blanks were small (single determinations, and not true field blanks)
B. 13Corg
1. Samples prepared exactly as for CHN. Blank determinations again from single blank determinations.
Standardisation to NBS22 Oil, same as for SizeFractionatedPumped Particles - see that sheet.
2. Blank corrections from single Ag and QMA samples
Ag filter blank 1 punch 1 0.03 below detect 1.0
QMA-Blnk 2 punches 2 0.01 below detect 5.1
brass punch area(mm2)
13.59
Agfilter area (mm2) QMA filter area
411.14 15393.35
fraction sampled fraction sampled
by one Ag punch by oneQMA punch
0.03 0
SOIREE Size-Fractionated Th, POC/PON, 13Corg results (Trull, Charette)
13Corg data reported in Trull and Armand, DSR-II.