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A review of evidence for a Gulf of Tonkin location for the Australasian tektite source crater |
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| รหัสดีโอไอ | |
| Creator | Aubrey Whymark |
| Title | A review of evidence for a Gulf of Tonkin location for the Australasian tektite source crater |
| Contributor | - |
| Publisher | Department of Mineral Resources of Thailand |
| Publication Year | 2564 |
| Journal Title | Thai Geoscience Journal |
| Journal Vol. | 2 |
| Journal No. | 2 |
| Page no. | 1 ถึง 30 |
| Keyword | Australasian tektite, Gulf of Tonkin, impact crater, Pleistocene, Song Hong Basin, Yinggehai Basin |
| URL Website | http://www.dmr.go.th/ewtadmin/ewt/tgjdmr/ewt_news.php?nid=23 |
| Website title | กรมทรัพยากรธรณี, THAI GEOSCIENCE JOURNAL |
| ISSN | 2730-2695 |
| Abstract | Australasian tektites (AAT) occur across Southeast Asia, Australia, the Indian Ocean, andsouthwest Pacific Ocean. AAT form the youngest and most extensive major tektite strewn field.Unlike other tektite strewn fields, AAT have no known source crater. Review of the literatureestablishes that a single ~43 km post-impact diameter crater exists, possibly significantly enlargedby slumping. The obliquity of the impact that formed the AAT would result in a crater that is lesspervasive in depth but with greater downrange shock effects and melt ejection. Multiple lines ofevidence, historically viewed in isolation, were examined, concatenated, contextualized, anddiscussed. Tektite morphology and distribution; microtektite regressions; geochemicalconsiderations, comparisons, and iso-concentration regressions; lithological characteristics; ageof source rock; and regional geological considerations are reviewed. The source material ispredicted to be an abnormally thick sequence of rapidly deposited, poorly compacted, deltaic toshallow marine, shales to clay-rich siltstones of early Pleistocene to Pliocene age. The impactlikely occurred in a shallow marine environment. Forty-two maps of positive and negativeparameters are presented and overlain. These indicate the AAT source crater probably lies in thecentral to northwestern Yinggehai - Song Hong Basin / Gulf of Tonkin. This geochemicallyoptimal setting is characterized by exceptionally high sedimentation rates that explain the 10Beand Rb-Sr age discrepancy, the seawater signature, and apparent absence of a crater by rapidburial. |
