Multiproxy taphonomic analysis in the Los Colorados Formation (Upper Triassic), Ischigualasto-Villa Unión Basin, Argentina: A case study through sauropodomorph remains. (October 2022)

• Record Type: Journal Article
• Authors: Pérez, Leandro M.; Otero, Alejandro; Alonso Muruaga, Pablo J.; Gaetano, Leandro C.; Leardi, Juan M.; Krapovickas, Verónica; Poiré, Daniel G.
• Is Part Of: Journal of South American earth sciences. Volume 118(2022)
• Publication Date: 2022-10
• Subjects: Dinosaurs -- Taphonomy -- Upper Triassic -- Ischigualasto-Villa Unión basin -- Gondwana; Geology -- Latin America -- Periodicals; Earth sciences -- Latin America -- Periodicals; Geology -- Antarctica -- Periodicals; Earth sciences -- Antarctica -- Periodicals; Geology -- Caribbean Area -- Periodicals; Earth sciences -- Caribbean Area -- Periodicals; Géologie -- Amérique latine -- Périodiques; Sciences de la terre -- Amérique latine -- Périodiques; Géologie -- Antarctique -- Périodiques; Sciences de la terre -- Antarctique -- Périodiques; Géologie -- Caraïbes (Région) -- Périodiques; Sciences de la terre -- Caraïbes (Région) -- Périodiques; Earth sciences; Geology; Antarctica; Caribbean Area; Latin America; Periodicals; 550.5
• DOI: 10.1016/j.jsames.2022.103925
• Languages: English
• ISSNs: 0895-9811

Abstract

Abstract: We present the first taphonomic analysis on basal sauropodomorph dinosaur remains from the Los Colorados Formation. We analyzed 22 bone samples with X-ray diffractometry, three of these in petrographic sections and one of them in SEM. In this article we recognize the taphonomic processes (biostratinomic and fossil-diagenetic) involved in the genesis of the 'La Esquina Local Fauna'. Regarding fossil diagenesis, it was possible to recognize the different processes that acted on the bone remains. In this sense, we analyzed different types of fracture present in the bones and their relationship with expansion generated by changes in the volume of minerals (for example, carbonates, gypsum and anhydrite). Finally, the importance of more taphonomic studies throughout the Los Colorados Formation is highlighted in order to better understand the vertebrate fossil record it contains. Highlights: Sauropodomorph bones were affected by different taphonomic processes. At least three types of fractures associated with volume changes of minerals. The fractures analyzed in the bones are of fossil-diagenetic origin. The fossil record of vertebrate remains is found in well-developed overbank/floodplain deposits and rarely within fluvial channel facies. Major bone loss can be explained by actual exhumation.