The role of volcanic-derived clays in the preservation of Ediacaran biota from the Itajaí Basin (ca. 563 Ma, Brazil)
Open Access
- 3 March 2021
- journal article
- research article
- Published by Springer Science and Business Media LLC in Scientific Reports
- Vol. 11 (1), 1-10
- https://doi.org/10.1038/s41598-021-84433-0
Abstract
The early evolution of metazoans has been reconstructed by studies on exceptionally preserved molds in siliciclastic rocks from the Ediacaran Period. However, there remains considerable controversy regarding the formation mechanisms of this unusual ‘Ediacaran-style’ preservation. Proposed hypotheses usually include early authigenesis of minerals, but evidence for this is scarce. In a recently discovered deposit of Ediacaran biota in Brazil, we show that the classic moldic preservation is related to clay mineral authigenesis. Specifically, these clays originated from the alteration of original pyroclastic sediments, likely enhanced by microbial activity, leading to early illitization and morphological templating of the fossiliferous surfaces at a micrometric scale. Such high-fidelity preservation was made possible by rapid burial during volcanic events and the in-situ templating of tissue by clays via microbially-mediated mineralization. This newly described Lagerstätte demonstrates that a number of minerals can facilitate preservation, and that perhaps ‘Ediacaran-style’ preservation result from different processes leading to the same broad style of preservation.This publication has 44 references indexed in Scilit:
- Early Cretaceous volcanism and its impact on fossil preservation in Western Liaoning, NE ChinaPalaeogeography, Palaeoclimatology, Palaeoecology, 2011
- The Itajaí foreland basin: a tectono-sedimentary record of the Ediacaran period, Southern BrazilInternational Journal of Earth Sciences, 2010
- Depositional age and provenance of the Itajaí Basin, Santa Catarina State, Brazil: Implications for SW Gondwana correlationPrecambrian Research, 2010
- Silurian brachiopods with soft-tissue preservationNature, 2005
- Microbial mediation of authigenic clays during hydrothermal alteration of basaltic tephra, Kilauea VolcanoGeochemistry, Geophysics, Geosystems, 2002
- Microbiotic Formation of Silicate Minerals in the Weathering Environment of a Pyroclastic DepositClays and Clay Minerals, 2002
- Authigenic mineralization and detrital clay binding by freshwater biofilms: The Brahmani river, IndiaGeomicrobiology Journal, 1998
- Formation of Allophane and Beidellite during Hydrothermal Alteration of Volcanic Glass Below 200°CClays and Clay Minerals, 1992
- The preservation of fossil leaves in Cretaceous volcaniclastic rocks from Alexander Island, AntarcticaGeological Magazine, 1982
- PRESERVATION OF SOFT‐BODIED ANIMALS IN PRECAMBRIAN SANDSTONES AT EDIACARA, SOUTH AUSTRALIALethaia, 1968