Radium isotope measurements from bottom waters in the South Atlantic Bight from 2015-2020 (SAB BMA project) (NCEI Accession 0291982)

This dataset contains chemical data collected from 2015-06-02 to 2020-05-11. These data include depth, radium-223, radium-224, radium-226, and radium-228. The instruments used to collect these data include Gamma Ray Spectrometer, Pump, and Radium Delayed Coincidence Counter. These data were collected by James Pinckney and Willard S. Moore of University of South Carolina at Columbia as part of the "Groundwater sources of "new" N for benthic microalgal production in the South Atlantic bight (SAB BMA)" project. The Biological and Chemical Oceanography Data Management Office (BCO-DMO) submitted these data to NCEI on 2022-11-02.

The following is the text of the dataset description provided by BCO-DMO:

Radium isotope measurements from bottom waters in the South Atlantic Bight from 2015-2020

Dataset Description:
Acquisition Description:
Methods & Sampling

Bottom water samples were obtained by lowering a submersible pump to near the seafloor and filling two 26-liter carboys. Subsamples for salinity were usually taken from each sample and measured with a YSI conductivity meter to confirm the CTD measurement. Radium samples were filtered through a column of Mn-fiber to quantitatively remove Ra [Moore, 1976]. The Mn-fiber was returned to the lab, where short-lived radium isotopes ( 223 Ra, half-life = 11.4 days, and 224 Ra, half-life = 3.66 days) were measured using a delayed-coincidence counting system [Moore and Arnold, 1996]. After the short-lived measurements were complete, Ra and Mn were stripped from the Mn-fiber and radium was coprecipitated with BaSO 4 and transferred to a small tube. 226 Ra and 228 Ra were measured by gamma spectrometry after 222 Rn had equilibrated with 226 Ra [Moore et al., 1985]. The RaDeCC systems were calibrated for 224Ra with a NIST standard solution of 232Th adsorbed to Mn-fiber and for 223Ra by the technique of Moore and Cai [2013]. The gamma detector was calibrated with NIST standard solutions for 226 Ra and 228 Ra in a BaSO 4 matrix [Moore, 1984].

Samples were taken from R/V Trinity, owned by a private charter company called Charleston SCUBA. This company is no longer in operation.