Silicified biotas from the Mesozoic of Antarctica: towards a research renaissance of an extraordinary Lagerstätte

• Applicant: Professor Dr. Benjamin Bomfleur
• Subject Area: Geology
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 500787157

The remote mountain ranges of Antarctica host extraordinary plant-fossil deposits that are of great importance for our understanding of the past polar forests of Gondwana. Triassic and Jurassic terrestrial sedimentary successions there contain various silica permineralizations, in which plants, fungi and microbes may be preserved three-dimensionally and fine histological and cellular detail, enabling detailed reconstructions of the biology and ecology of the fossil organisms. Especially the study of Triassic silicified peat deposits has, over the course of fifty years, yielded an unprecedented wealth of data, making this one of the most important sources of information on Mesozoic vegetation altogether. The focused and lasting research effort of the U.S. Antarctic Programme has, however, concentrated almost entirely on just a single occurrence of silicified peat in the Beardmore Glacier region, whereas similar occurrences have hardly been studied at all. During several GANOVEX expeditions (German Antarctic North Victorialand Expedition), numerous new plant-fossil sites in the North of Victoria Land, more than 1000 km afield, were discovered and sampled. Among these are three remarkable occurrences of plant-bearing silicified deposits: (1) silicified peat and wood from previously unknown Triassic deposits; (2) a volcanoclastic debris-flow deposit with abundant silicified plant remains from Early Jurassic lake deposits; and (3) the unique occurrence of up to 5 m tall, silicified tree trunks preserved upright within Early Jurassic lava flows in the Mesa Range area. This project proposal aims to generate a first in-depth assessment of the exceptionally preserved terrestrial palaeoecosystems of northern Victoria Land by dedicating a PhD project to the comprehensive and detailed analysis of the existing collections from these three plant-fossil occurrences. In a series of six specific project tasks dedicated to particular taxa and taxon assemblages, polished sections and petrographic thin sections will be prepared and analysed via light microscopy in order to resolve structural details at the highest possible quality and resolution. The results will (1) provide insights into the composition, structure, and functioning of Mesozoic terrestrial palaeoecosystems of northern Victoria Land; (2) allow, for the first time, a comparison with the hitherto unique material from the Triassic of the Beardmore Glacier region and the Jurassic of Tasmania; and (3) contribute to a better understanding of the dramatic biotic and palaeoenvironmental changes from the Triassic into the Early Jurassic.

• DFG Programme: Research Grants