Evaluating and comparing geochemical sampling protocols in dinosaur eggshells: refining Cretaceous ecosystem research

Coimbra, Rute ; Moreno-Azanza, Miguel (Universidad de Zaragoza) ; Ezquerro, Lope (Universidad de Zaragoza) ; Núñez-Lahuerta, Carmen ; Gasca, José Manuel ; Immenhauser, Adrián ; Mateus, Octávio ; Rocha, Fernando

Resumen: The geochemical signatures of dinosaur eggshells represent well-established proxies in paleoenvironmental and paleobiological research. The variable sampling procedures reported in the literature, however, deserve attention. In order to evaluate the impact of different sampling methodologies on carbon and oxygen isotope and elemental concentrations, grinding was contrasted with drilling to extract powder samples from eggshell fragments collected at several locations. Eggshell data were further contrasted with surface materials, encasing matrix and compared with independent proxies using petrographic and elemental techniques. Iron and manganese elemental concentrations revealed an enrichment sequence depending on the sampling strategy for the same eggshell fragment. This pattern can be mistaken for a variable state of preservation. In contrast, carbon and oxygen isotope values exhibited only subtle differences and lacked clear trends. This suggests that isotope data are less susceptible to different methodological approaches. It is shown that drilling offers a wider range of possibilities compared to grinding (e.g., faster and less destructive). Additionally, drilled powder samples can confidently be used for elemental and isotope analysis, excluding contamination, thus providing a more accurate set of proxy data from eggshell archives.

Idioma: Inglés

DOI: 10.1016/j.cretres.2023.105632

Año: 2023

Publicado en: Cretaceous Research 151 (2023), 105632 [10 pp.]
ISSN: 0195-6671

Factor impacto JCR: 1.9 (2023)

Categ. JCR: PALEONTOLOGY rank: 12 / 57 = 0.211 (2023) - Q1 - T1
Categ. JCR: GEOLOGY rank: 11 / 61 = 0.18 (2023) - Q1 - T1

Factor impacto CITESCORE: 4.1 - Paleontology (Q1)

Factor impacto SCIMAGO: 0.734 - Paleontology (Q1)

Financiación: info:eu-repo/grantAgreement/ES/DGA-FEDER/E18 Aragosaurus-Recursos Geológicos y Paleoambientes
Financiación: info:eu-repo/grantAgreement/ES/MICINN/FJCI-2020-044561-I
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PLEC2021-008203/AEI/10.13039/501100011033
Financiación: info:eu-repo/grantAgreement/ES/MICINN/RYC2021-034473-I
Financiación: info:eu-repo/grantAgreement/ES/NextGenerationEU/PRTR

Tipo y forma: Article (Published version)

Área (Departamento): Área Paleontología (Dpto. Ciencias de la Tierra)