Geodigest

Many years ago, scientists assumed that the round depression in which one of the vineyards in the south of France is located is actually a meteorite crater (Fig. 1). But then they abandoned this idea. Now a new confirmation has been found for it (The Universe Magazine, 23 February 2023). Geologist and cosmochemist Professor Frank Brenker from Goethe University in Frankfurt was on vacation and travelling in France when his attention was attracted by a winery named ‘Domaine du Météore’. The fact is that one of its vineyards is located in a circular depression with a depth of 30 m and a diameter of 220 m. Back in the 1950s, its unusual shape led to the theory that it was an ancient crater from a meteorite fall. Though scientists refuted this assumption, the name associated with meteorites remained. Brenker decided to study the possible crater in detail, because he believed that alternative geological explanations simply did not satisfy all the features of this place. He selected rock samples and examined them in the laboratory. The presence of mica veins, a characteristic trace of meteorite impacts, was immediately detected. Prof. Brenker also found traces of breccia in the samples— potentially formed as a result of meteorite impacts. The researchers were convinced that the vineyard could be a meteorite crater and in the following year gathered a large team to study it on the spot. First of all, it turns out that the magnetic field in the vineyard is much weaker than in its surroundings. This is also very typical for meteorite craters. The team was finally convinced of the correctness of the assumption by the discovery of spheres made of iron and nickel with a diameter of about 1 mm. They are formed exclusively by explosions of ‘heavenly rocks’. Despite the fact that meteorites regularly crash into Earth, traces of these events are difficult to find due to the fact that erosion erases them in a few hundreds and thousands of years, especially where it rains intensively. There are only 190 impact craters registered worldwide. There are only three known in Western Europe. These are the Rochechouart in Aquitaine, France, the Nördlinger Ries between the Swabian Alb and the Franconian Jura, and the Steinheim Basin near Heidenheim in BadenWürttemberg (both in Germany). Now they will be joined by another one at the French winery.