PANGAEA_990366 Total Thorium-234 Activity in water column along the equatorial Atlantic collected on RV METEOR during cruise M181 Cape Town - Mindelo, 2022-04-17 - 2022-05-27 Bam, Wokil Total Thorium-234 Activity in water column along the equatorial Atlantic collected on RV METEOR during cruise M181 Cape Town - Mindelo, 2022-04-17 - 2022-05-27 2026-02-11 PANGAEA Dataset https://doi.pangaea.de/10.1594/PANGAEA.990366 Investigator Wokil Bam wokil.bam@usm.edu Earth Science LATITUDE LONGITUDE Event label Identification Sample ID DATE/TIME DEPTH, water Thorium-234 Thorium-234, error Uranium-238 Uranium-238, error geoscientificInformation CTD/Rosette CTD025 CTD026 CTD027 CTD028 CTD032 CTD033 CTD034 CTD036 CTD038 CTD039 CTD040 CTD041 CTD044 CTD045 CTD046 CTD048 CTD049 CTD051 CTD052 CTD053 CTD056 CTD057 CTD058 CTD060 CTD062 CTD063 CTD064 CTD069 CTD070 CTD071 CTD075 CTD077 CTD078 CTD082 CTD084 CTD088 M181 M181_102-1 M181_107-1 M181_117-1 M181_124-1 M181_126-1 M181_131-1 M181_146-1 M181_153-1 M181_156-1 M181_165-1 M181_170-1 M181_182-1 M181_185-1 M181_189-1 M181_204-1 M181_214-1 M181_216-1 M181_227-1 M181_238-1 M181_241-1 M181_243-1 M181_253-1 M181_265-1 M181_267-1 M181_272-1 M181_285-1 M181_288-1 M181_290-1 M181_298-1 M181_303-1 M181_309-1 M181_71-1 M181_76-1 M181_81-1 M181_83-1 M181_88-1 M181_96-1 M181_99-1 Microstructure Profiler Radiometer Anti-coincidence beta counters, Risø Laboratory Calculated from salinity Meteor (1986) 2022-04-30 2022-05-20 Complete 0.0 0.0 -44.0 2.0 5.0 m (DEPTH, water) 6000.0 m (DEPTH, water) GEOTRACES Global marine biogeochemical cycles of trace elements and their isotopes access rights needed CC-BY-4.0: Creative Commons Attribution 4.0 International (License comes into effect after moratorium ends) English PANGAEA Data Publisher for Earth & Environmental Science https://www.pangaea.de/ Data Center Contact Michael Diepenbroek info@pangaea.de

Leobener Str.

Bremen Bremen 28359 Germany online 2664 data points text/tab-separated-values Clevenger, Samantha J; Benitez-Nelson, Claudia R; Drysdale, Jessica A; Pike, Steven M; Puigcorbé, Viena; Buesseler, Ken O (2021): Review of the analysis of 234Th in small volume (2–4 L) seawater samples: improvements and recommendations. Journal of Radioanalytical and Nuclear Chemistry, 329(1), 1-13, https://doi.org/10.1007/s10967-021-07772-2 Owens, Stephanie A; Buesseler, Ken O; Sims, Kenneth W W (2011): Re-evaluating the 238U-salinity relationship in seawater: Implications for the 238U–234Th disequilibrium method. Marine Chemistry, 127(1-4), 31-39, https://doi.org/10.1016/j.marchem.2011.07.005 Pike, Steven M; Buesseler, Ken O; Andrews, J; Savoye, N (2005): Quantification of Th-234 recovery in small volume sea water samples by inductively coupled plasma-mass spectrometry. Journal of Radioanalytical and Nuclear Chemistry, 263, 355-360

Total water-column Thorium-234 was determined by following the methods of Pike, et al. (2005) and Clevenger, et al. (2021) on 2-liter (L) water column samples, as mentioned in International GEOTRACES cookbook. An exact 1-milliliter (mL) aliquot of 230Th (50.03 disintegrations per minute per gram (dpm g⁻¹)) was used as the yield monitor and added during initial acidification of the samples. QMAs were used to collect the precipitate from the 2 L process and immediately dried. Once dried, they were mounted onto plastic 25-millimeter (mm) discs, covered with a mylar layer and two layers of aluminum foil, and immediately beta counted at sea. The filters were counted again, 5 to 6 months later to quantify the background radioactivity due to the beta decay of long-lived natural radionuclides that are also precipitated. The mean value of the at-sea counts (decay-corrected to the time of collection) minus the background value for each filter is reported as the 234Th activity (dpm L⁻¹). Activities for 234Th are generally reported in disintegrations per minute per liter (dpm L⁻¹). Data are decay-corrected to the mid-point time between when the first and last bottles were fired for shallow casts, when the messenger was dropped for deep casts, and the time of collection for fish tow samples. All data have been recovery-corrected using the 230Th /229Th recovery method (see References) to account for any loss of sample material during processing. All samples were analyzed using Risø Laboratory Anti-Coincidence Beta Counters, using a helium/1% butane mixture. Uranium-238 is calculated as a function of salinity described in Owens et al., 2011. ** For all details see the full metadata description at "https://doi.pangaea.de/10.1594/PANGAEA.990366"!

http://en.wikipedia.org/wiki/ISO_6709 LATITUDE http://en.wikipedia.org/wiki/ISO_6709 LONGITUDE http://en.wikipedia.org/wiki/ISO_8601 DATE/TIME https://doi.org/10.1007/s10967-021-07772-2 Review of the analysis of 234Th in small volume (2–4 L) seawater samples: improvements and recommendations https://doi.org/10.1016/j.marchem.2011.07.005 Re-evaluating the 238U-salinity relationship in seawater: Implications for the 238U–234Th disequilibrium method https://en.wikipedia.org/wiki/RV_Meteor_(1986) Meteor (1986) https://www.geotraces.org/ GEOTRACES DIF 9.4 2026-02-11 2026-04-29