New Evidence Suggests Libyan Desert Glass Formed by Meteorite Impact
The formation of Libyan desert glass (LDG) has been the subject of a longstanding debate in planetary science. Various theories have been proposed, including the suggestion that the glass was formed as a result of lighting, unusual geological processes, or even volcanic activity on the Moon. However, new evidence suggests that the glass was likely created by a meteor slamming into the desert.
For the past 25 years, researchers have been exploring two main scenarios for the formation of LDG: either it was created by a meteorite impacting the desert surface, or by the airburst of a meteorite exploding in the atmosphere. A recent study, led by Dr. Elizaveta Kovaleva from the University of the Western Cape, sought to differentiate between these two scenarios.
The team of international researchers used transmission electron microscopy to study the detailed composition of the glass. They found tiny crystals of zircon oxides, which provided crucial evidence for the impact scenario. These crystals, including a rare configuration known as cubic zirconia, indicated that the glass was formed under high temperatures and extreme pressure, consistent with a meteorite impact.
“These are very tiny particles of mineral phases that only form at very high pressures. And those high pressures can only be realized in the Earth’s crust following the impact of meteorites. And they were preserved in LDG because they are so small,” explained Dr. Kovaleva.
The study, published in American Mineralogist, provides strong evidence in support of the impact scenario for the formation of LDG. However, one major question remains unanswered: if there was an impact, where is the crater? Researchers are currently searching for potential impact sites, and are encouraging the public, particularly those who speak French, to assist in the search.
The findings of this study shed new light on the mysterious origins of Libyan desert glass and contribute to our understanding of meteorite impacts on Earth.