High resolution taphonomy of conulariids from the pimenteira formation, Parnaíba Basin, Tocantins

• Grant number: 22/03527-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2022
• End date: March 31, 2023
• Field of knowledge: Biological Sciences - Zoology - Paleozoology
• Principal Investigator: Renato Pirani Ghilardi
• Grantee: Ana Laura Dangio
• Host Institution: Faculdade de Ciências (FC). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil

Abstract

Conulariids are extinct invertebrate scyphozoans, sessile of epifauna, benthic, with generally phosphatic and elongated theca and, most often, with four faces. Most of the species in this group are from shallow marine and platform waters. In contrast to the quantity and frequency of publications focused on conulariids from the Paraná Basin, research in the Parnaíba Basin is sparse and precarious. Therefore, we intend to identify the taphonomic processes involved in the deposition of conulariids, using organisms from the western portion of the Parnaíba Basin as a tool for paleoenvironmental and paleobiogeographic interpretations of the Devonian of the Pimenteira Formation. The present work will rely on the high-resolution taphonomic analysis of 26 rock samples with specimens of Conularia Quichua, belonging to an outcrop of the Pimenteira Formation on the western edge of the Parnaíba Basin. Initially, the samples will be described, cleaned, and photographed to observe the anatomical details. A precise understanding of the stratigraphic profile of the TO-51 outcrop will also be made for the sedimentary description of the rocks where the conulariids were deposited, as well as the analysis of the samples in the Scanning Electron Microscope. Preliminary studies with these samples were carried out in 2021, noting that conulariids can be classified as paraautochthonous and allochthonous, since most are preserved horizontally to the bedding plane and with the preservation of only two thecae.(AU)