Laser fluorometric analysis of plants for uranium exploration

Journal of Geochemical Exploration
By: , and 

Metrics

10
Crossref references
Web analytics dashboard Metrics definitions

Links

Abstract

A preliminary test of biogeochemical exploration for locating uranium occurrences in the Marfa Basin, Texas, was conducted in 1978. Only 6 of 74 plant samples (mostly catclaw mimosa, Mimosa biuncifera) contained uranium in amounts above the detection limit (0.4 ppm in the ash) of the conventional fluorometric method. The samples were then analyzed using a Scintrex UA-3 uranium analyzer - an instrument designed for direct analysis of uranium in water, and which can be conveniently used in a mobile field laboratory. The detection limit for uranium in plant ash (0.05 ppm) by this method is almost an order of magnitude lower than with the fluorometric conventional method. Only 1 of the 74 samples contained uranium below the detection limit of the new method. Accuracy and precision were determined to be satisfactory. Samples of plants growing on mineralized soils and nonmineralized soils show a 15-fold difference in uranium content; whereas the soils themselves (analyzed by delayed neutron activation analysis) show only a 4-fold difference. The method involves acid digestion of ashed tissue, extraction of uranium into ethyl acetate, destruction of the ethyl acetate, dissolution of the residue in 0.005% nitric acid, and measurement.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Laser fluorometric analysis of plants for uranium exploration
Series title Journal of Geochemical Exploration
DOI 10.1016/0375-6742(81)90091-1
Volume 15
Issue 1-3
Year Published 1981
Language English
Publisher Elsevier
Description 7 p.
First page 617
Last page 623
Country United States
State Texas
Other Geospatial Marfa Basin
Additional publication details