Reactive iron in marine sediments

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

56

Scientific paper

A combined field/laboratory study has been undertaken to explore the mineralogy, concentrations and reactivity (towards sulfide) of iron in marine sediments. Also considered is the importance of bacterial Fe liberation in regulating pore-water chemistry. Two contrasting marine environments are included; one is the relatively Fe-poor FOAM site and the other is the Fe-rich sediment of the subaqueous Mississippi Delta. Results show that oxide minerals are the most important Fe phases in early diagenetic pyrite formation. However, viewed separately, lepidocrocite and ferrihydrite are more reactive towards sulfide than goethite and hematite. When Fe oxides are present in relatively high concentrations, dissolved sulfide is nearly absent from sediment pore waters (with concomitant high concentrations of dissolved Fe), even in the presence of active sulfide production by sulfate reduction. A combination of experimental results and diagenetic modelling shows that in some sediments pore water Fe finds it origin in the bacterial reduction of iron oxides. This seems the case even though greater amounts of Fe are reduced by reaction of sulfide with iron oxides. It appears that distinct microenvironments may exist in marine sediments, where, in one microenvironment, sulfide reacts with Fe oxides locally precipitating Fe sulfide minerals. In another, Fe reduced and solubilized by microorganisms migrates freely into solution.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Reactive iron in marine sediments does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Reactive iron in marine sediments, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Reactive iron in marine sediments will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1803371

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.