Dataset: Helium isotope with helium and neon concentration data from Leg 2 (Hilo, HI to Papeete, French Polynesia) of the US GEOTRACES Pacific Meridional Transect (PMT) cruise (GP15, RR1815) on R/V Roger Revelle from Oct-Nov 2018

Final no updates expectedDOI: 10.26008/1912/bco-dmo.862220.1Version 1 (2021-09-30)Dataset Type:Cruise Results

Principal Investigator: William J. Jenkins (Woods Hole Oceanographic Institution)

Co-Principal Investigator: Christopher R. German (Woods Hole Oceanographic Institution)

BCO-DMO Data Manager: Shannon Rauch (Woods Hole Oceanographic Institution)


Program: U.S. GEOTRACES (U.S. GEOTRACES)

Project: US GEOTRACES Pacific Meridional Transect (GP15) (U.S. GEOTRACES PMT)

Project: Measurement of Helium Isotopes on the U.S. GEOTRACES Alaska-Tahiti Section (GP15) (PMT Helium Isotopes)


Abstract

This dataset includes helium isotope, helium, and neon concentration data from Leg 2 (Hilo, HI to Papeete, French Polynesia) of the US GEOTRACES Pacific Meridional Transect (PMT) cruise (GP15, RR1815) on R/V Roger Revelle from October to November 2018.

Water samples were transferred from Niskin bottles and stored in crimped copper tubing. Gases were extracted from the water samples in a shore-based vacuum system and stored in aluminosilicate glass ampoules. The extracted gases were analyzed for helium and neon concentrations using ion counting in a quadrupole mass spectrometer and for helium isotopes using a magnetic sector dual-collecting isotope ratio mass spectrometer. Details are given in Jenkins et al. (2019) and Stanley et al. (2007).

Note: Natural and bomb tritium will decay to 3He in the copper tubing water sample container between the time the water sample was acquired and when the gases were extracted. We account for this using tritium concentrations estimated from a prior (2015) cruise occupation extrapolated in time and interpolated in space to the sample location and time. The size of this effect is significant in shallow, northern waters and vanishingly small in deeper and more southerly waters.

SPECIAL NOTE: The sample obtained from Station 21, Cast 11, Bottle 1 (5440 dbar) is excluded because the helium and nutrient results clearly indicate that tbe bottle has either pre/post-tripped or leaked and is not representative of the other bottles tripped at/near this depth. To our knowledge, ODF has not flagged this bottle as invalid, so be aware that any results from this particular water sample (station/cast/bottle) should be ignored.

 


Related Datasets

Continues

Dataset: GP15 He Isotope C(He) and C(Ne) - Leg 1
Relationship Description: GP15 was made up of two cruise legs, RR1814 (Leg 1) and RR1815 (Leg 2).
Jenkins, W. J., German, C. R. (2021) Helium isotope with helium and neon concentration data from Leg 1 (Seattle, WA to Hilo, HI) of the US GEOTRACES Pacific Meridional Transect (PMT) cruise (GP15, RR1814) on R/V Roger Revelle from September to October 2018. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2021-09-30 doi:10.26008/1912/bco-dmo.862182.1
IsRelatedTo

Dataset: GP15 Heavy Noble Gas Concentrations Leg 2
Relationship Description: Both datasets were generated from the same samples.
Jenkins, W. J., German, C. R. (2022) Concentrations of dissolved argon, krypton, and xenon from Niskin bottle samples collected on Leg 2 (Hilo, HI to Papeete, French Polynesia) of the US GEOTRACES Pacific Meridional Transect (PMT) cruise (GP15, RR1815) on R/V Roger Revelle from Oct-Nov 2018. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2022-08-10 doi:10.26008/1912/bco-dmo.877899.1

Related Publications

Methods

Jenkins, W. J., Lott, D. E., & Cahill, K. L. (2019). A determination of atmospheric helium, neon, argon, krypton, and xenon solubility concentrations in water and seawater. Marine Chemistry, 211(1), 94–107. doi:10.1016/j.marchem.2019.03.007
Methods

Stanley, R. H. R., Baschek, B., Lott, D. E., & Jenkins, W. J. (2009). A new automated method for measuring noble gases and their isotopic ratios in water samples. Geochemistry, Geophysics, Geosystems, 10(5), n/a–n/a. doi:10.1029/2009GC002429