Ben Creisler
Recent papers not yet mentioned, with free pdfs:
This work presents a detailed structural and morphological analysis of different dinosaur eggshells such as Spheroolithus (sample 1, 2), lambeosaurinae, Prismatoolithus, and one unidentified ootaxon performed by high-resolution scanning electron microscopy (HRSEM). These ancient eggshells of Late Cretaceous dinosaurs were collected in the coastal area of El Rosario, Baja California in Mexico. Additionally, a thorough study was performed on the elements present in the samples by different techniques such as energy-dispersive spectroscopy (EDS), X-ray fluorescence (XRF), and X-ray photoelectron spectroscopy (XPS). The XPS technique was performed to make an accurate identification of the compounds of two different types of eggshells (Spheroolithus sample 1 and Prismatoolithus). This contribution compares the surface of five different dinosaur eggshells of 74 Ma and their inner section to determine the morphology, distribution of the chemical elements present, as well as their relationship. The observed morphology of the ornithopod eggshells of the herbivorous species shows that the mammillary cones are in the form of columns with microaggregates and irregular pores. In contrast, in the theropod eggshells, the mammillary cones are observed in different forms with wider pores. Finally, the chemical components present in the structures of each of the samples were estimated using the information obtained from SEM-EDS, evidencing the presence of calcite, quartz, and albite in each of the samples. The composition reveals that eggshells contain Si, P, S, K, Ca, Mn, Fe, and Sr and trace elements such as Cr, Cu, and Zn. The presence of heavy metals may be an indication that the eggshells presented diagenetic alterations.
News:
Cracking the secrets of dinosaur eggshells
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Dendroolithus dashiqiaoensis oosp. nov.Â
JIA Songhai, FANG Kaiyong, GAO Diansong, GAO Yongli, CHANG Huali, CHANG Fei, XIAO Le, YANG Lili, ZHENG Yalin, ZHU Xufeng, WANG Qiang & WANG Xiaolin (2020)
A new oospecies of dinosaur eggs from the Upper Cretaceous in the Xichuan Basin, Henan Province.
Acta Geologica Sinica 94(10): 2816-2822 (Chinese edition)
http://www.geojournals.cn/dzxbe/ch/reader/view_abstract.aspx?file_no=2020362&flag=1Free pdf:
http://www.geojournals.cn/dzxbe/ch/reader/create_pdf.aspx?file_no=2020362&flag=1&journal_id=dzxbe&year_id=2020
The discovery and research of dinosaur eggs in Xichuan basin began in 1974. Dinosaur eggs in Xichuan basin have very high diversity. There are 4 oofamilies, 6 oogenera and 6 oospecies, especially dendroolithids. In recent years, during the investigation of geoheritages in Henan Province by Henan Geological Museum, some new types of dinosaur eggs have been found again in Xichuan basin. Here we describe one of them. According to the following characteristics: the shell unit is an irregular branch with multi branches, the eggshell thickness is 1.62~1.74 mm, the cone gap is obvious, the shell unit begins to branch from the upper part of the cone, the middle part of the eggshell has 3~4 branches, and a fusion layer is formed near the outer surface of the eggshell, and the eggshell has complex pore system, we establish a new oospecies Dendroolithus dashiqiaoensis oosp. nov. Studying the classification and correlation of dinosaur eggs in Xichuan basin, the distribution of different types of dinosaur eggs in the strata, it will promotes the division of red beds in the basin, which will provide more detailed paleobiological evidence for the division and correlation of red beds, paleogeography, paleoenvironment and paleoclimate in the different Mesozoic basins in the eastern Qinling Mountains.
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