Mysterious glass in the Atacama Desert may be from an ancient exploding comet

[smp]

From LiveScience.com:
"Mysterious bits of twisted glass strewn across Chile's Atacama Desert may have originated from a large comet that exploded in Earth's atmosphere around 12,000 years ago, according to a new study.

The ancient explosion — which may have been multiple back-to-back explosions — would have produced intense winds as strong as tornadoes and scorching heat that burned the desert sand, transforming it into silicate glass, or a solid that contains silicon and oxygen in a particular structure."

https://www.livescience.com/glassy-rock ... ient-comet

Thanks to a fellow member here for pointing me to this one!

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[Makuser]

Hi Stephen. A very interesting article. There are many occurrences of mineral alterations on Earth not due to flowing water (metastasis). Fulgurite glass is formed when lightning strikes sand (usually on a beach) but this is only small tubular specimens of fused silica. Then we have Obsidian glass, which is formed in a volcanic region but there is no evidence of any volcano activity in the Atacama Desert region in the past. Then there is Moldavite (vitreous silica projectile glass), from the Moldau (Vltava) river in Bohemia (the Czech Republic), from where the first described pieces came and also in southern Germany (Nördlinger Ries Crater). It was formed by a meteorite impact that probably occurred about 15 million years ago. However, a key here is the carbon14 recent dating in the 75 kilometer–long swath and the presence of Zircon which makes this find and re-evaluation interesting. To convert Zirconium Silicate into Zirconium Oxide (Baddeleyite) requires a temperature of 3,040 degrees Fahrenheit or higher and large winds to form the twisted samples found at the Atacama Desert.

Thanks for the great read report Stephen and keep up the news reports.

[GCoyote]

Very interesting. There was a documentary a few years back about a similar find in Libya. - https://en.wikipedia.org/wiki/Libyan_desert_glass

Marshall might have more insight into how these minerals compare to each other.

[Makuser]

Hi Gary. Thanks for your response and sorry that I am late getting back onto this thread but have been busy with Thanksgiving festivities and guests here. I too saw the article that you mentioned about the desert glass in Libya (and western Egypt). It too has the signature of an extraterrestrial impact found at the Atacama Desert. It also includes specimens of trinitite (also called atomsite). Specimens are also found in the Yucca Flats, Nevada craters and near Alamogordo, New Mexico from the US testing of atomic bombs in the mid/late 1940's (part of the Manhattan Project) and later. Now getting back to the Atacama Desert, carbon 14 testing of the underlying ground places the event at about 12,000 years ago. Archeo/Geologists believe that at this time the region was a grassy flat land. However, even a large grassland fire could not get hot enough to form the Baddeleyite specimens found on this site. This lends more evidence to another extraterrestrial impact. Can you imaging how any indigenous people living in this area at that time must have felt after witnessing this event? I hope this helps Gary and Stephen and have a great weekend.

[Groovy2]

really interesting- Thanks