I’m pleased to announce the publication of an article describing how fossils can be preserved within carbonate ooids, and what the implications are for this new aspect of taphonomy (the study of fossil preservation) we call ooimmuration. The team of authors include me, Anna Cooke (’20), fellow Wooster Professor Shelley Judge, and ace paleontologist Dr. Tim Palmer. The fieldwork for this project was done primarily on the Team Utah 2019 Expedition to the Middle Jurassic Carmel Formation exposed north of St. George.
The image above shows a microscopic view of a thin-section cut through Carmel ooids. Fossils are inside these ooids, most notably a calcareous foraminiferan in the center.
The abstract: Ooimmuration is here defined as a taphonomic process by which fossils are preserved within ooids. It is a form of lithoimmuration, although depending on the role of microbes in the formation of the ooid cortex, ooimmuration can also be considered a type of bioimmuration. Fossils enclosed within ooids are protected from bioerosion as well as the abrasion common in energetic depositional environments such as ooid shoals. Many taxa in some fossil assemblages may be known only because they were ooimmured. We describe as examples of ooimmuration fossils preserved in an oolite from the Middle Jurassic (Bajocian) Carmel Formation in southwestern Utah.
Now go forth and find more examples of ooimmuration!
Wilson, M.A., Cooke, A.M., Judge, S.A. and Palmer, T.J. 2021. Ooimmuration: Enhanced fossil preservation by ooids, with examples from the Middle Jurassic of southwestern Utah, USA. Palaios 36: 326-329. (https://doi.org/10.2110/palo.2021.036)