Australian Tektite Source Crater Identified

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In summary, tektites are small natural glass nodules found in about ten areas of the Earth's surface. In the 60s and 70s, their origin was debated, with possibilities including volcanic ejecta or the product of bolide impact. It is now accepted that they are produced by meteorite impacts. The sources of most of the strewn fields have been identified, but the source of the Australasian field was unknown until a recent paper by Kerry Sieh et al. The paper presents evidence that the impact crater is buried beneath the Bolaven volcanic field in Southern Laos. This discovery has significant implications for our understanding of tektites and their formation.
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Australasian tektite strewn field sourced from newly recognised impact crater in southern Laos.
Tektites are small (up to a few centimetres), natural glass nodules, shaped as ovoids, spheres and dumbbells. They are found in about ten areas of the Earth's surface. In the 60s and 70s their origin was debated. Possibilities included volcanic ejecta from terrestrial or lunar volcanoes, or the product of bolide impact. It is now generally accepted that they are produced by large meteorite impact. Terrestrial rock fragments, melted by the impact and thrown to high altitudes cool rapidly to glass during descent. ( wikipedia overview)

The sources of all but one of the resultant strewn fields have been identified. The authors of a recent PNAS paper believe the missing impact crater, responsible for the Australasian field, has now been found.

Kerry Sieh et al, Australasian impact crater buried under the Bolaven volcanic field, Southern Laos Proceedings of the National Academy of Sciences, Dec 2019

Abstract

The crater and proximal effects of the largest known young meteorite impact on Earth have eluded discovery for nearly a century. We present 4 lines of evidence that the 0.79-Ma impact crater of the Australasian tektites lies buried beneath lavas of a long-lived, 910-km3 volcanic field in Southern Laos: 1) Tektite geochemistry implies the presence of young, weathered basalts at the site at the time of the impact. 2) Geologic mapping and 40Ar-39Ar dates confirm that both pre- and postimpact basaltic lavas exist at the proposed impact site and that postimpact basalts wholly cover it. 3) A gravity anomaly there may also reflect the presence of a buried ∼17 × 13-km crater. 4) The nature of an outcrop of thick, crudely layered, bouldery sandstone and mudstone breccia 10–20 km from the center of the impact and fractured quartz grains within its boulder clasts support its being part of the proximal ejecta blanket.
 
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Ophiolite said:
Summary:: Australasian tektite strewn field sourced from newly recognised impact crater in southern Laos.

Kerry Sieh et al, Australasian impact crater buried under the Bolaven volcanic field, Southern Laos Proceedings of the National Academy of Sciences, Dec 2019

Yup, I was reading this elsewhere a couple of weeks ago. Very cool.
The source has for a long while ( years) been suggested as somewhere in SE Asia, nice to know that it's
been pinned down
I have a number of tektites from this source/strewn field, including...
Australia,

Tektites Australia.jpg


Philippines

Philippine Tektites - #023 sm.jpg


Thailand

Tektites Thailand.jpg


Dave
 
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Wow, this is really interesting! I had no idea that tektites were formed by meteorite impacts. It's amazing how much we are still learning about our planet and its history. I'll definitely have to check out that PNAS paper. Do you have any thoughts on the significance of this discovery? Will it change our understanding of tektites and their formation?
 

Related to Australian Tektite Source Crater Identified

What is a tektite?

A tektite is a type of glassy rock that is formed when a large meteorite strikes the Earth's surface at high speeds. The intense heat and pressure from the impact melts the surrounding rocks and ejects them into the air, where they cool and solidify into tektites.

What is the significance of identifying the source crater for Australian tektites?

Identifying the source crater for Australian tektites is significant because it provides valuable information about the geological history of the region. It can also help scientists understand the impact event that created the tektites and its potential effects on the environment and life on Earth.

How was the source crater for Australian tektites identified?

The source crater for Australian tektites was identified through a combination of geological and geophysical studies. Scientists analyzed the chemical composition and age of the tektites, as well as the surrounding rocks and sediments. They also used remote sensing techniques, such as satellite imagery and gravity surveys, to map the area and identify potential impact structures.

What is the name of the source crater for Australian tektites?

The source crater for Australian tektites is known as the East Warburton Basin Impact Structure. It is located in the Warburton Basin in Western Australia and is estimated to be around 120 million years old.

What are the potential implications of this discovery?

This discovery has several potential implications, including furthering our understanding of impact events and their effects on Earth's history. It could also have economic implications, as the identification of the source crater could lead to the discovery of valuable minerals and resources in the area.

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