Magnetic measurements and pollutants of sediments from Cauvery and Palaru River, India

• Published in: Environmental earth sciences Vol. 56; no. 2; pp. 425 - 437
• Main Authors: Chaparro, Marcos A. E, Sinito, Ana M, Ramasamy, V, Marinelli, Claudia, Chaparro, Mauro A. E, Mullainathan, S, Murugesan, S
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.11.2008; Springer-Verlag; Springer; Springer Nature B.V
• Subjects: Earth and Environmental Science; Earth Sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Freshwater; Geochemistry; Geology; Geophysics: general, magnetic, electric and thermic methods and properties; Heavy metals; Internal geophysics; Magnetism; Marine and continental quaternary; Original Article; Pollutants; Pollution, environment geology; Sediments; Surficial geology; Asia; Tamil Nadu India; India; ISW, India, Tamil Nadu; Environmental magnetism; Pollution; River sediments; Multivariate statistical techniques; Magnetic enhancement; stream transport; magnetite; isothermal remanent magnetization; oxides; heavy metals; metals; concentration; indicators; pollution; multivariate analysis; spatial distribution; pollutants; spinel; River sediments . Pollution; grain size; alluvium; contamined sites; magnetic susceptibility; remanent magnetization; statistical analysis; size distribution
• ISSN: 0943-0105; 1866-6280; 1432-0495; 1866-6299
• DOI: 10.1007/s00254-007-1180-1

Rock-magnetic techniques have become a useful tool in environmental issues; in particular, magnetic studies constitute an alternative way to study pollution in different media. The present contribution focuses on magnetic parameters as pollution indicators, especially from their relationship with contents of heavy metals. The work was carried out in two Indian rivers located in Tamil Nadu, southern India. Several sediment samples were collected and studied in the laboratory using magnetic techniques, magnetic susceptibility, anhysteric remanent magnetization, isothermal remanent magnetization, and chemical techniques to determine contents of heavy metals. Magnetic mineralogy indicates the predominance of ferrimagnetic minerals; although magnetite-like minerals are the main magnetic carriers, antiferromagnetic minerals can be present as subordinate carriers. Concentration-dependent magnetic parameters revealed noticeable differences between both rivers, e.g. magnetic susceptibility is four times higher in Cauvery than in Palaru River. Moreover, such increase can be interpreted as “magnetic enhancement” and therefore related to the pollution status. This magnetic enhancement indicated a different pollutant contribution in both rivers, and also, a different spatial distribution along these rivers, where critical (or more polluted) sites were identified. On the other hand, univariate and multivariate statistical analyses--e.g. PCoordA, Multifactorial Analysis of distance, PCA and RDA--were examined, revealing a link between magnetic and chemical variables. Among magnetic parameters, the concentration-dependent magnetic parameters (e.g. magnetic susceptibility) seem to be the most relevant for this study.