Abstract
/sup 226/Ra and other uranium-series radionuclides have been measured in a suite of marine phosphorite samples from the upwelling area off Peru/Chile by gamma-ray spectrometry and radiochemical techniques. Our results lead to the following conclusions: (1) phosphorite nodules typically show unidirectional growth at rates of 1 to 10 mm/Kyr; (2) very young samples (less than a few thousand years) contain slight excess amounts of /sup 226/Ra probably derived from pore fluids; and (3) slow but persistent leakage of /sup 226/Ra out of phosphate nodules occurs resulting in systematically lower /sup 226/Ra ages compared to /sup 230/Th ages for samples older than about twenty thousand years. Radium fluxes from these phosphate nodules appear to be 1 to 3 orders of magnitude less than those calculated for deep-sea sediments and ferromanganese nodules.
Citation Formats
Kim, K H, and Burnett, W C.
/sup 226/Ra in phosphate nodules from the Peru/Chile seafloor.
United Kingdom: N. p.,
1985.
Web.
doi:10.1016/0016-7037(85)90320-5.
Kim, K H, & Burnett, W C.
/sup 226/Ra in phosphate nodules from the Peru/Chile seafloor.
United Kingdom.
https://doi.org/10.1016/0016-7037(85)90320-5
Kim, K H, and Burnett, W C.
1985.
"/sup 226/Ra in phosphate nodules from the Peru/Chile seafloor."
United Kingdom.
https://doi.org/10.1016/0016-7037(85)90320-5.
@misc{etde_5412109,
title = {/sup 226/Ra in phosphate nodules from the Peru/Chile seafloor}
author = {Kim, K H, and Burnett, W C}
abstractNote = {/sup 226/Ra and other uranium-series radionuclides have been measured in a suite of marine phosphorite samples from the upwelling area off Peru/Chile by gamma-ray spectrometry and radiochemical techniques. Our results lead to the following conclusions: (1) phosphorite nodules typically show unidirectional growth at rates of 1 to 10 mm/Kyr; (2) very young samples (less than a few thousand years) contain slight excess amounts of /sup 226/Ra probably derived from pore fluids; and (3) slow but persistent leakage of /sup 226/Ra out of phosphate nodules occurs resulting in systematically lower /sup 226/Ra ages compared to /sup 230/Th ages for samples older than about twenty thousand years. Radium fluxes from these phosphate nodules appear to be 1 to 3 orders of magnitude less than those calculated for deep-sea sediments and ferromanganese nodules.}
doi = {10.1016/0016-7037(85)90320-5}
journal = []
volume = {49:4}
journal type = {AC}
place = {United Kingdom}
year = {1985}
month = {Apr}
}
title = {/sup 226/Ra in phosphate nodules from the Peru/Chile seafloor}
author = {Kim, K H, and Burnett, W C}
abstractNote = {/sup 226/Ra and other uranium-series radionuclides have been measured in a suite of marine phosphorite samples from the upwelling area off Peru/Chile by gamma-ray spectrometry and radiochemical techniques. Our results lead to the following conclusions: (1) phosphorite nodules typically show unidirectional growth at rates of 1 to 10 mm/Kyr; (2) very young samples (less than a few thousand years) contain slight excess amounts of /sup 226/Ra probably derived from pore fluids; and (3) slow but persistent leakage of /sup 226/Ra out of phosphate nodules occurs resulting in systematically lower /sup 226/Ra ages compared to /sup 230/Th ages for samples older than about twenty thousand years. Radium fluxes from these phosphate nodules appear to be 1 to 3 orders of magnitude less than those calculated for deep-sea sediments and ferromanganese nodules.}
doi = {10.1016/0016-7037(85)90320-5}
journal = []
volume = {49:4}
journal type = {AC}
place = {United Kingdom}
year = {1985}
month = {Apr}
}