The impact also hit a sandy layer of material near the surface, creating glassy green tektites. Tektites are impact melt glasses formed from material that’s thrown high into the atmosphere. They can often be found hundreds or thousands of kilometers from the original impact site.
In this case, they were found in Czechia near the River Moldau and are thus named moldavites. Unlike the diamonds at Ries, moldavite occurs in large-enough specimens to be used in jewelry as a semiprecious stone.
Still more craters to be found
The five impact craters above are diverse, and could all be considered unique. None of them have exhausted all the scientific questions we could ask.
Excitingly, there are still more craters we could find on Earth. As satellite imaging datasets become readily available at even higher resolutions, we are able to identify more potential impact structures in remote areas. Field geologists could explore these and search for the structures and chemical signals of an impact.
Each crater – no matter how old or how obscured – is ready to teach us something new about our planet, our solar system, and the geological processes that shape it.
Helen Brand, Senior Beamline Scientist – Powder Diffraction, Australian Nuclear Science and Technology Organisation