Project ImpCHAR – characterising the energy flux from small impact cratering processes
Estimates of the current impact flux on Earth show that within the lifetime of our species it is likely that a significant meteroid impact will hit a populated area.
Small meteroids (<50 m in diameter) that are large enough to reach the Earth’s surface and form am impact crater, represent the most likely hazard, because smaller bodies are more common than large ones, and because positions of small meteoroids are not efficiently tracked by the current Near Earth Objects search programs.
The formation of Carancas crater in 2007 and the fall of Chelabinsk meteor in 2012 are examples of such events (from the smallest range side) that were not foreseen by any of these programs.
Existing observational and modelling approaches have found it hard to quantify the thermal energy release from small impact cratering processes. Most methods used to study and characterise small impact craters and the energy processes associated with them are based on approaches used to assess large impact craters with high temperature transitions includes field evidence that assesses the presence of shatter cones, diaplectic mineral glasses, high pressure mineral phases, high-temperature glasses and melts as well as planar deformation features.
However, these extreme energy signatures do not apply to lower energy small meteroid impact craters, in unconsolidated target rocks. Project ImpCHAR aims to develop a novel toolkit with which to identify and characterise small impact events and estimate the energy that they release.
Key contact: Ania Losiak – A.I.Losiak[at]exeter.ac.uk