ANR ET-Megafire

Tropical megafires generated by tectonic-producing extraterrestrial impacts in the Quaternary

We propose to characterise the response of the continental biosphere to large impact craters, in particular through the megafires generated, linked to the melting of the Earth's surface.

The study of tektites, i.e. long-distance ejected impact glass, will be central to the project. Three tectite-producing impacts on forested areas in Nicaragua, Ghana and Indochina since 1.1 Ma will be studied. The environmental response to the impact, indicated by pollen, charcoal etc., will be studied in various marine and lacustrine archives. The reaction between molten material and biomass (elements such as C, P, S) will be traced using the compositional variability of tektites explored in a systematic way, as well as the nano-scale characterisation of inclusions in tektites such as phosphates, metal, etc.

We will thus shed new light on the processes of tectonic formation and the response of ecosystems to megafires