Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Moles, N. R. Articles by Murphy, P. J. Search for Related Content GeoRef GeoRef Citation

Replacement and authigenic mineralogy of metal contaminants in stream and estuarine sediments at Newtownards, Northern Ireland

¹ School of the Environment, University of Brighton, Brighton BN2 4GJ, UK
² School of Geography, Queen’s University Belfast, Belfast BT7 1NN, UK
³ Institute of Mineralogy and Petrology, University of Leoben, Austria A-8700
⁴ School of Earth Sciences and Geography, Kingston University, Kingston upon Thames KT1 2EE, UK

^* E-mail: n.moles{at}bton.ac.uk

Tidal mudflats are locally enriched in heavy metals at the head of Strangford Lough in Northern Ireland, where drainage from the hinterland enters the sea lough via a tidal canal in an urban area. To characterize the metallic contaminants and investigate their provenance, heavy particles separated from stream, canal and estuarine sediments were analysed by electron microprobe and laser Raman microspectroscopic methods. Potential metal sources are mineralization in the catchment area and industrial or domestic pollution. Anthropogenic particles include metallic grains, alloys and compounds of Pb, Zn, Cu, Fe, Cr and Sn. Alteration of metallic particles includes de-zincification of brass in freshwater sediment and replacement of Cu wire by covellite in brackish to marine sediment. Mobility of Cu, Fe and S in canal and estuarine sediments is indicated by the authigenic growth of framboidal Fe sulphide on oxide substrates and of chalcopyrite rims on covellite. Intricate colloform and platy crystalline textures suggest a cyclical deposition of covellite and chalcopyrite under conditions of varying redox and salinity. Lead and Cr mobility in the contaminated estuarine sediment is shown by the authigenic formation on Pb-rich substrates of heterogeneous Pb- and Cr-rich sulphate-phosphate compounds and Pb-oxychlorides.

KEYWORDS: contaminated sediments, authigenic sulphides, covellite, chalcopyrite, Pb compounds, Strangford Lough, Northern Ireland

This article has been cited by other articles:

				J. L. Jambor, M. Raudsepp, and K. Mountjoy MINERALOGY OF PERMEABLE REACTIVE BARRIERS FOR THE ATTENUATION OF SUBSURFACE CONTAMINANTS Can Mineral, December 1, 2005; 43(6): 2117 - 2140. [Abstract] [Full Text] [PDF]

				K. Pye Forensic examination of rocks, sediments, soils and dusts using scanning electron microscopy and X-ray chemical microanalysis Geological Society, London, Special Publications, January 1, 2004; 232(1): 103 - 121. [Abstract] [PDF]