Bahamian Stromatolite Carbonate Precipitation

Miriam Andres (now at Chevron) Pam Reid (RSMAS) and I worked through the RIBS project to study carbonate precipitation in Bahamian stromatolites. Fine-grained, precipitated aragonite in the stromatolites has a lower carbon isotopic ratio than trapped and bound grains (ooids and shell fragments). We interpret these results as demonstrating that aragonite is precipitating in an environment where heterotrophic activity is affecting the composition of mat DIC. This is consistent with Pieter Visscher's observations that sulfate reduction is abundant in layers in the stromatolites with petrographic evidence for abundant aragonite precipitation (see P.T. Visscher, R.P. Reid, and B.M. Bebout, Geology; October 2000; v. 28; no. 10; p. 919-922).

Related Publications:

Andres, Miriam S., Dawn Y. Sumner, R. Pamela Reid, and Peter K. Swart, 2006. Abstract
Carbon isotopic fingerprints of microbial respiration in modern marine stromatolites. Geology, v. 34, p. 973-976. DOI: 10.1130/G22859A.1

Reid R.P., C. Dupraz, P.T. Visscher, and D.Y. Sumner, 2003. Abstract
Microbial processes forming modern marine stromatolites: Microbe-mineral interactions with a three-billion-year rock record, in Fossil and Recent Biofilms, a natural history of life on Earth, W. E. Krumbein, D. M. Paterson, and G. A. Zavarzin, editors. Kluwer Academic Publishers, p. 103-118.

Andres, Miriam S., R. Pamela Reid, Dawn Y. Sumner, Pieter T. Visscher, and Peter K. Swart, 2006.
Isotopic fingerprinting of modern marine stromatolites. International Sedimentary Congress.

Andres, M.S., R.P. Reid, and D.Y. Sumner, 2005.
Isotopic fingerprinting of modern marine stromatolites. 24th Meeting International Association of Sedimentologists, Abstracts.

Andres, M.S., D.Y. Sumner, P.T. Visscher, P.K. Swart, and R.P. Reid, 2005.
Microbe-mineral interactions along biogeochemical gradients in Bahamian stromatolites: Key to lithification and preservation, AGU Fall Meeting. Abstract B31A-0962.



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Dawn Y. Sumner
Department of Geology
University of California
Davis, CA 95616
dysumner@ucdavis.edu