TITLE:
Application of Multivariate Statistic of U, Th and Pb Concentrations and Pb Isotopic Signatures in the Assessment of Geogenic and Anthropogenic Sources in a U-Mineralized Area
AUTHORS:
Adriana Monica Dalla Vecchia, Jorge Carvalho de Lena, Ana Claudia Queiroz Ladeira
KEYWORDS:
Environmental Monitoring, Statistical Analysis, Lead Stable Isotopes, Anthropogenic Sources, Geogenic Sources
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.7 No.6,
June
10,
2019
ABSTRACT: This work presents a Principal Component Analysis
(PCA) study using Pbisotope signatures and U,
Th and Pb concentrations from groundwater, sediments and rocks (granites and
orthogneisses) of the Complex of Lagoa Real (Bahia, Brazil). This area is naturally enriched in U and Th, with the occurrence
of Pb derived from the radioactive decay of the elements (238U, 235U
and 232Th) in the form of their stable isotopes 206Pb, 207Pb
and 208Pb in addition to the natural isotope 204Pb. Sampling
was carried out in the rainy season (December to January) and the points were
selected according to regional hydrology and geology. Thirty samples were
analyzed: 12 of groundwater (AP) and 18 of sediments (S). The results show that the
use of isotopic ratios allows discrimination between geogenic and anthropogenic
samples. This information is not obtained using only the analysis of
concentration data. Statistically, the isotopic data of Pb stand out as an
efficient tool in the characterization of sources in the scenario investigated,
allowing an effective environmental monitoring and a better management of the
mining activities.