INVESTIGADORES
CARMONA Noelia Beatriz
artículos
Título:
Mineral precipitation on modern siliciclastic tidal flats colonized by microbial mats
Autor/es:
CUADRADO, D.G.; CARMONA, N.B.; BOURNOD, C.N.
Revista:
SEDIMENTARY GEOLOGY
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2012 vol. 271 p. 58 - 66
ISSN:
0037-0738
Resumen:
The preservation and cementation of sedimentary structures under the influence of microorganisms in
siliciclastic environments have been poorly studied in contrast to carbonatic settings, where they have
been extensively investigated. Whereas in carbonatic environments, microbial mat-induced precipitation
of calcium carbonate results in a cementation process producing a quick lithification, in siliciclastic environments
other minerals would act as cement. The focus of this paper is to document the presence of authigenic
minerals within a biosedimentary fabrics and the possible link of these minerals with the extensive microbial
mats that colonize the tidal flat of the temperate Bahía Blanca estuary. Anoxic minerals (e.g. pyrite) and
authigenic zeolites such as analcime, clinoptilolite, mordenite, phillipsite and chabazite were recognized
through SEM and EDX analyses. These minerals were most likely formed by alteration of volcanic ash,
which is present in this tidal flat and also silica may result from dissolution of frustules of benthic diatoms.
Minerals precipitated in this setting are significant as they would act as early cement in the eogenesis, enhancing
the preservation of sedimentary and biogenic structures.