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  • Author or Editor: B. Presley x
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Abstract  

The feasibility of using trace multielement data obtained from neutron activation analysis to identify the source of crude oil residues was recently demonstrated. This paper presents the concentrations of Br, Co, Cr, Sb, Sc, Zn, and V/Ni, for 30 crude oil residues collected from beaches (beach asphalt), using 1 g samples. The method does not require chemical separation or post-irradiation concentration. The average standard deviation for the V/Ni ratio was ±0.39.

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Abstract  

Compton suppression gamma-spectroscopy provides an efficient method for measuring the concentration of226Ra,228Ra, and210Pb in ocean sediments. The background reduction realized from the suppressed mode of operation provides an “active shield” to allow for the low-level counting required for these measurements. We have used the method to study the possible accumulation of radium from produced waters in sediments from Gulf of Mexico sites of varied distances from drill platforms. In addition,210Pb levels were determined to evaluate the use of our spectrometer for this purpose. Baseline undisturbed concentrations have been obtained from the study of subsurface core material which predates drilling activities. Correlations of radium isotope concentrations with iron and barium provide information concerning the possible relationships between radium levels and drilling activity (excess barium) and natural variations in sediment texture (iron).

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