Inside of fossil shells, researchers have certificates for a previously unknown meteorite discovered in Florida. The shells contained tiny balls of rock glass – typical evidence of an impact. Their chemical composition also points to an extraterrestrial origin. Therefore, two to three million years one or more of the meteorite fell on or near the Florida Peninsula. The shells contained tiny balls of rock glass – typical evidence of an impact. While impact marks on the moon over millions of years on earth remain clearly visible, this is different. The erosion by wind and water, but also the vegetation quickly ensure that impact craters and other traces disappear. Betrayed often only subtle traces such as tiny globules of rock glass, so-called microtektites that it once an impact.
Mini balls in ancient shells in a rather unusual place
Mike Meyer from the Harrisburg University in Pennsylvania discovered such Mikrotektite. Still, he had to periods of study together with colleagues in Florida banks studied fossil shells – actually looking for micro-fossils in their interior. But when he opened some of the shells and the accumulated sediment durchsiebte in them, he discovered that tiny globule. “You really stood out. Because sand grains are typically rather irregular, potato-shaped”, says Meyer. “But I found this tiny, perfect balls.” More than 80 of these approximately 200 micrometers of small globules, Meyer on the circuit is found. But first, nobody knew what it was. For more than ten years he kept on until he recently found resistance and analyzed.
The balls were the extraterrestrial origin.
Their physical characteristics and their enrichment with exotic metals suggest that it is Mikrotektite – tiny testimonies of a meteoroid caldera. The globules formed when the tremendous energy of the impact melting and evaporation and hurled rocks to great heights. There solidified the rock drops to the small globules, before they fell back down to earth. The Mikrotektite now identified are the first ever found in Florida and the first in the fossil shells have been discovered. “I was really blown away,” says Meyer. Datings, ball in front of around two to three million years ago deposited. The researchers suspect that at that time, one or more of the meteorite on or near the Florida plateau must be taken.
However, is so far, why the microtektites contain an unusual amount of sodium. However, this rather volatile element usually evaporates during a meteorite crashes through the earth’s atmosphere. It is therefore unlikely that brought the sodium from the impactor, Meyer and his colleagues. You suspect that it comes rather from the site. “The high sodium content of the microtektites is exciting because it indicates a relatively close to a turning point,” said Meyer. “As the meteorite hit, he met probably a rock salt occurrences or the ocean.” Both speak for an impact location in or near Florida. “But we need still more material and archaeological sites, the source of this microtektites confirmed,” the researchers stress. You suspect that even more of these globules of rock glass in the mussel banks in the region could hide.