13C 18O bonds in carbonate minerals: A new kind of paleothermometer

Mathematics – Logic

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

33

Scientific paper

The abundance of the doubly substituted CO2 isotopologue, 13C18O16O, in CO2 produced by phosphoric acid digestion of synthetic, inorganic calcite and natural, biogenic aragonite is proportional to the concentration of 13C 18O bonds in reactant carbonate, and the concentration of these bonds is a function of the temperature of carbonate growth. This proportionality can be described between 1 and 50 °C by the function: Δ47 = 0.0592 · 106 · T-2 - 0.02, where Δ47 is the enrichment, in per mil, of 13C18O16O in CO2 relative to the amount expected for a stochastic (random) distribution of isotopes among all CO2 isotopologues, and T is the temperature in Kelvin. This relationship can be used for a new kind of carbonate paleothermometry, where the temperature-dependent property of interest is the state of ordering of 13C and 18O in the carbonate lattice (i.e., bound together vs. separated into different CO32- units), and not the bulk δ18O or δ13C values. Current analytical methods limit precision of this thermometer to ca. ± 2 °C, 1σ. A key feature of this thermometer is that it is thermodynamically based, like the traditional carbonate water paleothermometer, and so is suitable for interpolation and even modest extrapolation, yet is rigorously independent of the δ18O of water and δ13C of DIC from which carbonate grew. Thus, this technique can be applied to parts of the geological record where the stable isotope compositions of waters are unknown. Moreover, simultaneous determinations of Δ47 and δ18O for carbonates will constrain the δ18O of water from which they grew.

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

13C 18O bonds in carbonate minerals: A new kind of paleothermometer 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 13C 18O bonds in carbonate minerals: A new kind of paleothermometer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and 13C 18O bonds in carbonate minerals: A new kind of paleothermometer will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1136371

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