Research Objectives:
Over the past 30 years, the rocks of the central Transantarctic Mountains have been a source of outstanding plant fossil discoveries, including Permian and Triassic permineralized peat, fossil forests silicified in growth position, and compression floras with cuticular preservation. The rare juxtaposition of sites that include many different types of plant preservation, its exceptional quality, and the richness of the sites make this area unique.
We will collect Permian and Triassic plant megafossils from the Beardmore Glacier area (compression floras, especially those from Graphite Peak, and permineralized peats from Skaar Ridge and Fremouw Peak, both near Walcott Névé). Since permineralizations preserve a three-dimensional record of plant organs, they are important in understanding the basic morphology and anatomy of fossil plants, as well as detailing relationships among groups. The data provided by the juxtaposition of plant fossils preserved as permineralizations and compressions have already contributed greatly to our understanding of late Paleozoic–early Mesozoic plant evolution.
The Permian and Triassic represent an important time in plant evolution, and one about which we still know relatively little. The glossopterid seed ferns in the Permian and the corystosperms in the Triassic were the dominant plant groups in Gondwana. Since both groups had enclosed seeds, they have been proposed at one time or another as possible ancestors of flowering plants and have figured prominently in phylogenetic analyses of seed plants. Only through a combination of permineralizations and compressions is it possible to reveal a complete picture of fossil plants and, more importantly, to understand their position in seed plant evolution.
We will collect plants and silicified logs from Graphite Peak, which is believed to contain the Permian/Triassic boundary. Silicified logs have been noted in the lower Buckley Formation at this site, and these will be collected and examined for tree rings, which can be compared with tree rings in Late Permian wood (upper Buckley) from nearby Mount Achernar. The Late Permian has been assumed to be much warmer than Early-Middle Permian, and this should be reflected in the rings’ width and structure.
Our findings should lead to significant improvements in knowledge of plant evolution and paleoenvironmental conditions during the critical Permian to Triassic interval.
