Schwertmannite in wet, acid, and oxic microenvironments beneath polar and 
polythermal glaciers

Raiswell, R.; Benning, Liane G.; Davidson, L.; Tranter, M.; Tulaczyk, S.

doi:10.1130/g25350a.1

Item

ITEM ACTIONSEXPORT

Add to Basket

Local TagsRelease HistoryDetailsSummary

Released

Journal Article

Schwertmannite in wet, acid, and oxic microenvironments beneath polar and polythermal glaciers

Authors

Raiswell, R.
External Organizations;

/persons/resource/benning

Benning, Liane G.
0 Pre-GFZ, Departments, GFZ Publication Database, Deutsches GeoForschungsZentrum;

Davidson, L.
External Organizations;

Tranter, M.
External Organizations;

Tulaczyk, S.
External Organizations;

External Ressource

No external resources are shared

Fulltext (public)

There are no public fulltexts stored in GFZpublic

Supplementary Material (public)

There is no public supplementary material available

Citation

Raiswell, R., Benning, L. G., Davidson, L., Tranter, M., Tulaczyk, S. (2009): Schwertmannite in wet, acid, and oxic microenvironments beneath polar and polythermal glaciers. - Geology, 37, 5, 431-434.
https://doi.org/10.1130/g25350a.1

Cite as: https://gfzpublic.gfz-potsdam.de/pubman/item/item_806926

Abstract

Glacial and iceberg sediments contain nanoparticulates of schwertmannite, ferrihydrite, and goethite formed where pyrite was oxidized by dissolved oxygen in aqueous subglacial environments. Schwertmannite, typically found in acid mine drainage, only forms at low pH by the oxidative weathering of pyrite. Stoichiometric models show that these conditions can be created in closed-system microenvironments containing at least 10(-4) M dissolved oxygen, where volume ratios of water/pyrite are similar to 10(5) to 10(6). Ferrihydrite is the only product at higher and lower volume ratios. In these microenvironments the oxidation of pyrite to form schwertmannite is possible in several decades. Schwertmannite and ferrihydrite are metastable in contact with water and are transformed to goethite in <100 yr unless preserved in ice. The presence of these nanoparticulates demonstrates the existence of transient, acidic, and oxic aqueous microenvironments where enhanced biochemical and/or geochemical activity occurs beneath glaciers and ice sheets.