The composition and diagenesis of interstitial solutions--II. Fluxes and diagenesis at the water-sediment interface in the high latitude North and South Atlantic

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

13

Scientific paper

Studies of the major element composition of in situ sampled pore waters are reported for the North Atlantic and Southern Ocean between Africa and Antarctica. The pattern of diagenetic modification of pore water composition is similar throughout the entire Atlantic. Enrichment of Na + , Ca 2+ and alkalinity and depletion of Mg 2+ and K + are nearly universal. Only siliceous oozes consistently provide very limited evidence of cation diagenesis. The changes observed and the calculated fluxes across the seawater-sediment interface are much the same as those reported previously for other areas of the Atlantic and Caribbean. Fluxes of the major cations across the interface continue to be indicated as a major factor in the geochemical cycling of these elements, particularly Na + , Mg 2+ and K + . Diagenetic modelling indicates that aerobic oxidation of organic matter and consequent dissolution of CaCO 3 is a dominant reaction throughout the North Atlantic. The data indicate that O 2 oxidation to at least 30 cm is prevalent at nearly all stations. Dissolution of CaCO 3 in response to the introduction of metabolic CO 2 can lead to significant post-depositional modification of the sediments. The modelling also indicates a 1:1 stoichiometric relationship between Na + release and Mg 2+ uptake by sedimentary components. Although dissolved silica concentrations in biogenic siliceous sediments are among the highest yet reported (>700 M), calculations demonstrate that solubility control cannot be through equilibria with the mineral sepiolite. Further, the influence of cation-silicate surface phases, generally, upon solubility is contraindicated by Si(OH) 4 -Mg 2+ -H + relationships. Evaluation of the influence of fluid advection on pore water profiles indicates that at the stations studied in the North Atlantic, it is small. A more general consideration of the potential contribution of fluid advection to shaping interstitial water profiles demonstrates that advection can be a dominant factor. In such circumstances, serious misinterpretation of the nature of diagenetic reactions may result from a lack of knowledge and consideration of fluid advection.

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

The composition and diagenesis of interstitial solutions--II. Fluxes and diagenesis at the water-sediment interface in the high latitude North and South Atlantic 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 The composition and diagenesis of interstitial solutions--II. Fluxes and diagenesis at the water-sediment interface in the high latitude North and South Atlantic, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The composition and diagenesis of interstitial solutions--II. Fluxes and diagenesis at the water-sediment interface in the high latitude North and South Atlantic will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1688181

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