Mechanisms shaping the gypsum stromatolite-like structures in the Salar de Llamara (Atacama Desert, Chile).

ABSTRACT: The explanation of the origin of microbialites and specifically stromatolitic structures is a problem of high relevance for decoding past sedimentary environments and deciphering the biogenicity of the oldest plausible remnants of life. We have investigated the morphogenesis of gypsum stromatolite-like structures currently growing in shallow ponds (puquíos) in the Salar de Llamara (Atacama Desert, Northern Chile). The crystal size, aspect ratio, and orientation distributions of gypsum crystals within the structures have been quantified and show indications for episodic nucleation and competitive growth of millimetric to centimetric selenite crystals into a radial, branched, and loosely cemented aggregate. The morphogenetical process is explained by the existence of a stable vertical salini

SUBMITTER: Criado-Reyes J 

PROVIDER: S-EPMC9837060 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature