On the reliability of the Panalesis (v.0) paleogeographic maps

Palæogeography is the definition of the geography of the Earth in the geological past. However, geography depends on topography (both on land and under the sea) and the sea level which defines the coastline. Topography is a multifactorial resultant whose heart is the geodynamic context that created it (Vérard, 2019). In other words, there are no palæogeographic reconstructions if there is no plate tectonic model underlying them.

The palæogeographic maps presented here are derived from the Panalesis model (preliminary version or v.0), corresponding to palæo-digital elevation models (palæo-DEM) that cover the entire Phanerozoic on a global scale associated with sea level variations from Haq et al. (1987, 2008, 2018).

The results show two main facts. First, the main shortcomings of the method for converting a plate tectonic map to a palæogeographic map (Vérard et al., 2015) are relatively well understood and should be improved with new versions of the plate tectonic model (Verard, 2021) and the conversion code. Secondly, lithofacies databases (fossils and palæo-environments) on a global scale are needed to identify areas that are outside the “standard mode” defined by synthetic topographies and to understand the reasons for the discrepancies. Conversely, variations (global to regional) in lithofacies can only be understood if a quantified topographic model is proposed as a reference, which Panalesis is, to date, the only one to systematically offer.

 

REFERENCES

1. Vérard, C., 2019. Panalesis: Towards global synthetic palaeogeographies using integration and coupling of manifold models. Geological Magazine, 156 (2), 320-330.

2.1. Haq, B. U., Hardenbol, J., Vail, P. R., 1987. Chronology of fluctuating sea levels since the Triassic. Science, 235 (4793), 1156-1167.

2.2. Haq, B. U., Schutter, S. R., 2008. A chronology of Paleozoic sea-level changes. Science, 322 (5898), 64-68.

2.3. Haq, B. U., 2018. Triassic eustatic variations reexamined. The Geological Society of America (GSA Today), 28, 6 pages.

3. Vérard, C., Hochard, C., Baumgartner, P. O., Stampfli, G. M., 2015. 3D palaeogeographic reconstructions of the Phanerozoic versus sea-level and Sr-ratio variations. Journal of Palaeogeography, 4 (2), 167-188.

4. Vérard, C., 2021. 888 – 444 Ma global plate tectonic reconstruction with emphasis on the formation of Gondwana. Frontiers in Earth Science, 9 (666153), 28 pages.