Understanding the fate of iron in a modern temperate estuary: Leirárvogur, Iceland

• Published in: Applied Geochemistry
• Main Authors: Byrne, Gemma M., Worden, Richard H., Hodgson, David M., Polya, David A., Lythgoe, Paul R., Barrie, Craig D., Boyce, Adrian J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2011
• Subjects: Iceland
• Online Access: https://research.manchester.ac.uk/en/publications/d32f74dc-e3c0-4071-9c3d-834d0ec5a10f; https://doi.org/10.1016/j.apgeochem.2011.03.018

Fluvial dissolved Fe concentrations decrease upon mixing with seawater, resulting in the formation of Fe-floccules. However, a clear understanding of the fate of these floccules has yet to be established. Assessing how tidal processes affect the formation of Fe-colloids in the Leirárvogur estuary, SW Iceland, is an important step in understanding the formation and potential deposition of estuarine Fe-rich minerals within this estuarine system. The Leirárvogur estuary drains predominately Fe-rich basalt, increasing the likelihood of detecting changes in Fe-phases. Fluvial waters and local lake waters that drain into the estuary were compared and the effects of seasonal changes were considered, in an attempt to understand how varying end-members and external factors play a role in Fe-rich mineral formation. Aqueous and colloidal Fe concentrations were found to be greater towards the head of the Leirárvogur estuary, suggesting that potential Fe-rich minerals and complexes are forming at sites of fluvial input. Increasing suspended colloidal Fe towards the estuary mouth suggests that Fe-colloids are readily transported seaward. © 2011 Elsevier Ltd.