Could the Czech basin have been created through meteoritic impact?
This week the Czech newsmagazine Tyden reported on a theory that the so-called Czech basin, or massif, which makes up most of Bohemia, may have been created by a meteorite hitting the area around 2 billion years ago. The impact of the celestial object hitting the Earth would have been comparable to the force of many combined nuclear blasts. Generally, the Czech basin is thought to have been formed through plate tectonics, but now some scientists are considering a different possibility..
University professor and geologist Petr Rajlich, of the Museum of South Bohemia in Ceske Budejovice, is a researcher into the possible "cosmic" origins of the basin:
"The traditional explanation for the structure known as the Czech massif (basin) is that it was created through plate tectonics, that means through the collision of several 'micro-plates' around 380 to 320 million years ago. That explanation was first published in 1992 or '93."
JV: What led you to think that indeed the basin might have a different origin?
"The first impulse was the study of space photographs taken by American astronomers Professors Farouk el Baz and Michael Papagiannis which first noted the unusual circular form of the basin. They published a number of reports and abstracts considering the Czech massif as a meteoritic crater so big that it could not be observed from the Earth's surface.
"The explanation we have come up with to now is that 2 billion years ago a meteorite approximately 20 kilometres in diameter struck the Earth's surface and created a crater up to 300 kilometres in diameter, which was later solidified to the present shape of the basin."
JV: If one were to compare the impact of a meteorite such as this one?
"It would be comparable to the blast of thousands of nuclear bombs at the same time. Regarding the meteorite theory, we have found several lines of evidence, the first the occurrence of pseudotachylite black-shaded veins (formed by frictional melting) similar to outcrops at another crater in Sudbury, Canada and to the Vredefort crater in South Africa.
"We also found small diamonds found close to the border with Germany, shocked granites in the rock. Then there is the overall circular shape of the massif. These are some of the main lines of evidence. For me personally, I am very persuaded that this is the best 'working hypothesis' explaining the formation of the area."
