Linguliform brachiopods from the terminal Cambrian to lower Ordovician Tiñu section, Mexico
2007 (English)In: 51st Palaeontological Association Annual Meeting: Programme with Abstracts, 2007, 64- p.Conference paper (Other academic)
The Tiñu Formation of Oaxaca State (Mexico) is the only fossiliferous lower Palaeozoic unit between the Laurentian platform in northwest Mexico and Gondwanan successions in Andean South America. It has recently been shown that the Tiñu section is a condensed passive margin succession with Gondwanan character. The formation is divided into two members, i.e., the uppermost Cambrian Yudachica Member, which rests nonconformably on middle Proterozoic basement, and the Lower Ordovician (Tremadoc) Río Salinas Member. The formation has been studied with respect to its depositional environments and its fossil content of trilobites and conodonts, which both provide excellent biostratigraphical control for the formation. Linguliform brachiopods of twelve limestone horizons of the Tiñu Formation have been studied. The fauna comprises about five acrotretid taxa, a new siphonotretid species and a few linguloid fragments. Detailed investigations on taxonomy and stratigraphic distribution of the taxa are currently in progress. An assessment of the changes in brachiopod associations across the Cambrian-Ordovician boundary and in relation to the described environmental changes occurring throughout the formation is one of the main points of the investigation.
Place, publisher, year, edition, pages
2007. 64- p.
IdentifiersURN: urn:nbn:se:uu:diva-12594OAI: oai:DiVA.org:uu-12594DiVA: diva2:40363