SSP Stratigraphy, Sedimentology and Palaeontology
The 2019 Outstanding Student Poster and PICO (OSPP) Award is awarded to Theresa Nohl for the poster/PICO entitled:
Implications for cyclicity-based stratigraphic dating from the selective compaction and cementation of a halysitid coral from the Silurian of Gotland (Sweden) (Nohl, T.; Munnecke, A.)
Click here to download the poster/PICO file.
Theresa Nohl is a PhD student at the Friedrich-Alexander-University Erlangen-Nuremberg. Her research focuses on the formation of rhythmites, i.e. limestone-marl alternations. With approaches from sedimentology, taphonomy and geochemistry, she studies processes steering limestone-marl alternation formation. Her aims are (1) to distinguish early from late diagenesis, (2) to identify biases in the preservation of fossils, geochemical proxies and sedimentary structures caused by redistribution of CaCO3, and (3) to improve the understanding of interacting processes affecting limestone-marl alternation formation. At the EGU2019, Theresa presented a synsedimentary-grown Halysites (chain coral) colony from the Silurian of Gotland crosscutting several beds of the circumambient limestone-marl alternation. The limestone-marl alternation was identified to be of early diagenetic origin and mismatches the original environmental changes recorded in the coral’s skeleton. Furthermore, the short time span of a limestone-marl couplet deduced from the coral colony’s life span mismatches the assumed hundreds to thousands of years for a couplet in this calm deep setting. This renders interpreting and dating of this succession with cyclicity impossible.