Dataset Information

Australasian impact crater buried under the Bolaven volcanic field, Southern Laos.

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.

SUBMITTER: Sieh K

PROVIDER: S-EPMC6983392 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Australasian impact crater buried under the Bolaven volcanic field, Southern Laos.

Sieh Kerry K Herrin Jason J Jicha Brian B Schonwalder Angel Dayana D Moore James D P JDP Banerjee Paramesh P Wiwegwin Weerachat W Sihavong Vanpheng V Singer Brad B Chualaowanich Tawachai T Charusiri Punya P

Proceedings of the National Academy of Sciences of the United States of America 20191230 3

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 tha ...[more]

PMID: 31889003

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Dataset Information

Australasian impact crater buried under the Bolaven volcanic field, Southern Laos.

Publications

Australasian impact crater buried under the Bolaven volcanic field, Southern Laos.

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