Marine and Freshwater Research Marine and Freshwater Research Society
Advances in the aquatic sciences

Iron precipitate accumulations associated with waterways in drained coastal acid sulfate landscapes of eastern Australia

L. A. Sullivan A B and R. T. Bush A

A Centre for Acid Sulfate Soil Research, Southern Cross University, Lismore, NSW 2480, Australia.

B Corresponding author. Email:

Marine and Freshwater Research 55(7) 727-736
Submitted: 22 April 2004  Accepted: 16 August 2004   Published: 1 October 2004


Iron precipitate accumulations from surface environments surrounding waterways (such as the side of drains and soil surface horizons) in acid sulfate soil landscapes were analysed for their mineralogy, micromorphology and chemical properties. Schwertmannite (Fe8(OH)5.5(SO4)1.25) was the dominant mineral in these accumulations. Goethite (α-FeOOH) was the other iron precipitate mineral identified in these accumulations and the data indicate that this iron mineral was formed from schwertmannite, often as pseudomorphs after schwertmannite. The schwertmannite in these accumulations had similar morphology and chemical properties to schwertmannite reported for environments affected by acid mine drainage. The activity of Fe3+ in the drainage waters in these landscapes appears to be controlled by schwertmannite during both low flow (dry season) and flood conditions. Iron precipitate accumulations contained appreciable amounts of stored acidity (i.e. titratable actual acidity of between 164 and 443 mol (H+) t–1, and 1900 to 2580 mol (H+) t–1 of schwertmannite upon complete conversion to goethite) that tends to buffer these waters to very acidic conditions (i.e. pHs ~3.0–3.5). The relationship between water quality (i.e. pH and sulfate concentration) and type of iron precipitate mineral formed should enable the mineralogy of the iron precipitates in these surface environments to be used to help identify the degree of severity of degradation in these acid sulfate soil landscapes and to monitor the effectiveness of remediation programmes.

Extra keywords: geochemistry, goethite, micromorphology, mineralogy, schwertmannite, water quality.


Ahern C. R. McElnea A. E. Sullivan L. A. 2004 ‘Acid Sulfate Soils Laboratory Methods Guidelines.’ Department of Natural Resources, Mines and Energy Indooroopilly, Australia.

APHA 1998 ‘Standard Methods for the Examination of Water and Waste Water.’ 20th American Public Health Association–American Wastewater Association–World Environment Fund Washington, DC, USA.

Bigham J. M.Schwertmann U.Carlson L.Murad E.1990A poorly crystallized oxyhydroxysulfate of iron formed by bacterial oxidation of Fe(II) in acid mine waters.Geochimica et Cosmochimica Acta5427432758

Bigham J. M., Schwertmann U., and Carlson L. (1992). Mineralogy of precipitates formed by the biogeochemical oxidation of Fe(II) in mine drainage. In ‘Biomineralization Processes of Iron and Manganese: Modern and Ancient Environments’. (Eds H. C. W. Skinner and R. W. Fitzpatrick.) Catena Supplement 21, pp. 219–232. (Catena-Verlag: Reiskirchen, Germany.)

Bigham J. M.Carlson L.Murad E.1994Schwertmannite a new iron oxyhydroxysulfate from Pyhasalmi, Finland, and other localities.Mineral Magazine58641648

Bigham J. M.Schwertmann U.Traina S. J.Winland R. L.Wolf M.1996Schwertmannite and the chemical modelling of iron in acid sulfate waters.Geochimica et Cosmochimica Acta6021112121

Carlson L.Bigham J. M.Schwertmann U.Kyek A.Wagner F.2002Scavenging of As from acid mine drainage by schwertmannite and ferrihydrite: a comparison with synthetic analogues.Environmental Science & Technology3617121719doi:10.1021/ES0110271

Childs C. W.Inoue K.Mizota C.1998Natural and anthropogenic schwertmannites from Towada-Hachimantai National Park, Honshu, Japan.Chemical Geology1448186doi:10.1016/S0009-2541(97)00121-6

Dold B.Fontbote L.2001Element cycling and secondary mineralogy in porphyry copper tailings as a function of climate, primary mineralogy, and mineral processing.Journal of Geochemical Exploration74355doi:10.1016/S0375-6742(01)00174-1

Fanning D. S., Rabenhorst M. C., and Bigham J. M. (1993). Colors of acid sulfate soils. In ‘Soil Color’. (Eds J. M. Bigham and E. J. Ciolkosz.) SSSA Special Publication no. 13, pp. 91–108. (SSSA: Madison, WI, USA.)

Fanning D. S., Rabenhorst M. C., Burch S. N., Islam K. R., and Tangren S. A. (2002). Sulfides and sulfates. In ‘Soil Mineralogy with Environmental Applications’. SSSA Book Series no. 7, pp. 229–260. (SSSA: Madison, WI, USA.)

Ferguson A.Eyre B.1999Behaviour of aluminium and iron in acid runoff from acid sulphate soils in the lower Richmond River catchment.AGSO Journal of Australian Geology & Geophysics17193201

Fitzpatrick R. W. 2003 Overview of acid sulfate soil properties, environmental hazards, risk mapping and policy development in Australia. ‘Advances in Regolith’. Roach I. C. 122 125 CRC LEME Canberra, Australia.

Fitzpatrick R. W. Self P. G. 1997 Iron oxyhydroxides, sulfides and oxyhydroxysulfates as indicators of acid sulphate surface weathering environment. ‘Soils and Environment: Soil Processes from Mineral to Landscape Scale. Advances in GeoEcology 30’. Auerswald K. Stanjek H. Bigham J. M. 227 240 Catena-Verlag Reiskirchen, Germany.

Fitzpatrick R. W., Naidu R., and Self P. (1992). Iron deposits and microorganisms in saline sulfidic soils with altered soil water regimes in South Australia. In ‘Biomineralization Processes of Iron and Manganese: Modern and Ancient Environments’. (Eds H. C. W. Skinner and R. W. Fitzpatrick.) Catena Supplement 21, pp. 263–286. (Catena-Verlag: Reiskirchen, Germany.)

Lin C.Melville M. D.1993Control of soil acidification by fluvial sedimentation in an estuarine floodplain, Eastern Australia.Sedimentary Geology85271284

McElnea A. E. Ahern C. R. 2004 Actual acidity method. ‘Acid Sulfate Soils Laboratory Methods Guidelines’. Ahern C. R. McElnea A. E. Sullivan L. A. B2-1 B2-3 Queensland Department of Natural Resources, Mines and Energy Indooroopilly, Australia.

Murad E. 2002 Iron rich precipitates in mine drain environments: mineralogical characteristics and case studies. ‘Proceedings of the 17th World Congress of Soil Science, Thailand. 14–21 August 2002’.
p. 2078. (The Soil and Fertilizer Society of Thailand, Bangkok, Thailand.)

Murad E.Rojik P.2003Iron-rich precipitates in a mine drainage environment: Influence of pH on mineralogy.American Mineralogist8819151918

Parkhurst D. L. Appelo C. A. 1999 ‘User’s Guide to PhreeqC: a Computer Program for Speciation, Reaction Path, 1d-Transport and Inverse Geochemical Calculations.’ Water-resources Investigations Report 99–4259. U.S. Geological Survey Denver, CO, USA.

Piene A.Tritschler A.Kusel K.Peiffer S.2000Electron flow in an iron-rich acidic sediment-evidence for an acidity-driven iron cycle.Limnology and Oceanography4510771087

Regenspurg S.Brand A.Peiffer S.2004Formation and stability of schwertmannite in acidic mining lakes.Geochimica et Cosmochimica Acta6811851197

Sammut J.White I.Melville M. D.1996Acidification of an estuarine tributary in Eastern Australia due to drainage of acid sulfate soils.Marine and Freshwater Research47669684

Scheinost A. C.Schwertmann U.1999Color identification of iron oxides and hydroxysulfate: use and limitations.Soil Science Society of America Journal6314631471

Tulau M. J. 1999 a ‘Acid Sulfate Soil Management Priority Areas in the Lower Richmond Floodplain.’ Department of Land and Water Conservation Sydney, Australia.

Tulau M. J. 1999 b ‘Acid Sulfate Soil Management Priority Areas in the Lower Clarence Floodplain.’ Department of Land and Water Conservation Sydney, Australia.

Tulau M. J. Naylor S. D. 1999 ‘Acid Sulfate Soil Management Priority Areas in the Lower Macleay Floodplain.’ Department of Land and Water Conservation Sydney, Australia.

USEPA 1986 ‘Test Methods for Evaluating Solid Waste. Volume IA.’ 3rd
EPA/SW-846. (National Technical Information Service: Springfield, VA, USA.)

van Breeman N. 1972 Soil forming processes in acid sulphate soils. ‘Proceedings of the International Symposium on Acid Sulphate Soils, Wageningen, The Netherlands. 13–20 August 1972’.
(Ed. H. Dost.) ILRI Publication No. 18, pp. 66–128. (International Institute for Land Reclamation and Improvement: Wageningen, The Netherlands.)

van Breeman N. 1976 ‘Genesis and Acid Solution Chemistry of Acid Sulfate Soils in Thailand.’ PUDOC Wageningen, The Netherlands.

van Breeman N. 1982 Genesis, morphology, and classification of acid sulfate soils in coastal plains. ‘Acid Sulfate Weathering’.
(Eds J. A. Kittrick, D. S. Fanning and L. R. Hossner.) SSSA Special Publication 10. pp. 95–108. (Soil Science Society of America: Madison, WI, USA.)

Willet I. R. Melville M. D. White I. 1993 Acid drainwaters from potential acid sulphate soils and their impacts on estuarine ecosystems. ‘Selected Papers of the Ho Chi Min City Symposium on Acid Sulphate Soils’.
(Eds M. E. F. Mensvoort and D. Dent.) ILRI Publication No. 53, pp. 419–425. (International Institute for Land Reclamation and Improvement: Wageningen, The Netherlands.)

Williams D. J.Bigham J. M.Cravotta C. A.IIITrainaa S. J.Anderson J. E.Lyon J. G.2002Assessing mine drainage pH from the color and spectral reflectance of chemical precipitates.Applied Geochemistry1712731286

Export Citation