Comparison of Australasian tektites with Australasian microtektites and BeLaU spherules recovered from the ocean

TL;DR

This study compares the elemental compositions of Australasian tektites, microtektites, and BeLaU spherules, revealing similarities between tektites and crustal material, but distinct differences in BeLaU spherules, shedding light on their origins.

Contribution

It provides comprehensive elemental data for Australasian tektites and compares them with microtektites and BeLaU spherules, highlighting their compositional relationships and differences.

Findings

Australasian tektites and microtektites resemble upper continental crust.

BeLaU-spherules have distinct elemental patterns from Australasian tektites.

Elemental data supports crustal origin of Australasian tektites.

Abstract

The Australasian strewn field covers more than 15% of Earth's surface, consisting of tektites and microtektites. Australasian tektites from Southeast Asia and Australia, as well as microtektites recovered from deep sea sediments and Antarctica, are established to be derived from upper continental crust sediments. An expedition to retrieve remnants of bolide CNEOS 2014 January 8 (IM1), held in the Pacific Ocean, was in proximity to the known extent of the Australasian strewn field, and yielded "BeLaU"-spherules, whose compositions did not match most well-studied solar system material. We therefore report precise and comprehensive elemental data for Australasian tektites to compare their elemental abundances to those of microtektites from deep sea sediments, and BeLaU. Our findings corroborate previous studies that Australasian tektites and microtektites closely resemble the elemental abundance patterns of the upper continental crust. Meanwhile, the elemental patterns of the BeLaU-spherules are distinct from the Australasian tektite/microtektite compositions.