The stratified microbial community at Laguna Figueroa, Baja California, Mexico: A possible model for prephanerozoic laminated microbial communities preserved in cherts
The microbial mat community of the evaporite flat at North Pond, Laguna Figueroa (Baja California, Mexico) was actively involved in the production of laminated sediments prior to 1978. Heavy rains in 1979 and 1980 flooded the mat with 1 and 3 meters of meteoric water respectively. The flooding deposited up to 10 cm of silicoclastic sediment over theMicrocoleus-dominated mat and resulted in the cessation of laminated sediment deposition. In 1982, the surface had been recolonized by species of cyanobacteria (Spirulina, Oscillatoria) and purple photosynthetic bacteria (Chromatium, Thiocapsa). The silicoclastic sediments and residual evaporites, which overlaid the laminated sediment, had been reworked into an anaerobic, sulfide-rich mud and contained well preserved sheaths of filamentous and coccoid bacteria.
KeywordsOrganic Chemistry Geochemistry Microbial Community Chert Evaporite
Unable to display preview. Download preview PDF.
- 1.Awramik, S.M., 1982. The Pre-phanerozoic fossil record. In Mineral Deposits and the Evolution of the Biosphere, H.D. Holland and M. Schidlowski (eds.). Springer-Verlag, Berlin, pp. 67–82.Google Scholar
- 2.Horodyski, R.J., Bloesser, B. and Vonder Haar, S.J., 1977. Laminated algal mats from a coastal lagoon, Laguna Mormona, Baja California, Mexico.Journal of Sedimentary Petrology 47:680–696.Google Scholar
- 3.Knoll, A. and Barghoorn, E.S., 1977. Archean microfossils showing cell division from the Swaziland System of South Africa.Science 198:396–398.Google Scholar
- 4.Margulis, L., Barghoorn, E.S., Ashendorf, D., Banerjee, S., Chase, D., Francis, S., Giovannoni, S., and Stolz, J., 1980. The microbial community in the layered sediments at Laguna Figueroa, Baja California, Mexico: Does it have Precambrian analogues?Precambrian Research 11:93–123.Google Scholar
- 5.Margulis, L., Grosovsky, B.D.D., Stolz, J., Read, D., Lenk, S., and Lopez-Cortez, A., 1983. Distinctive microbial structure and the prePhanerozoic fossil record.Precambrian Research 20:Google Scholar
- 6.Reimer, T.O., Barghoorn, E.S. and Margulis, L., 1979. Primary productivity in an early Archean microbial ecosystem.Precambrian Research 9:93–104.Google Scholar
- 7.Stolz, J.F., 1983a. Fine structure of the stratified microbial community at Laguna Figueroa, Baja California, Mexico: I. Methods of in situ study of the laminated sediments.Precambrian Research 20:479–492.Google Scholar
- 8.Stolz, J.F., 1983b. Fine structure of the stratified microbial community at Laguna Figueroa, Baja California, Mexico: II. Transmission electron microscopy as a diagnostic tool in studying microbial communities in situ. In Microbial Mats, H.D. Halvorson, Y. Cohen, R. Castenholz (eds.). Alan Liss Publishing Co. (in press).Google Scholar
- 9.Walsh, M.M. and Lowe, D.R., 1983. Microfossils from cherts of the Kromberg formation.Science (in press).Google Scholar