![]() Low meltglass water content (0.02–0.05% H 2O) is consistent with a formation process similar to that of tektites and inconsistent with volcanism and anthropogenesis. This argues against formation of AH meltglass in thatched hut fires at 1100°–1200 ☌, and low values of remanent magnetism indicate the meltglass was not created by lightning. Alternately, melted grains of quartz, chromferide, and magnetite in AH glass suggest exposure to minimum temperatures of 1720 ☌ ranging to >2200 ☌. Approximately 40% of AH glass display carbon-infused, siliceous plant imprints that laboratory experiments show formed at a minimum of 1200°–1300 ☌ however, reflectance-inferred temperatures for the encapsulated carbon were lower by up to 1000 ☌. High YDB concentrations of iridium, platinum, nickel, and cobalt suggest mixing of melted local sediment with small quantities of meteoritic material. ![]() ![]() AH meltglass comprises 1.6 wt.% of bulk sediment, and crossed polarizers indicate that the meltglass is isotropic. At Abu Hureyra (AH), Syria, the 12,800-year-old Younger Dryas boundary layer (YDB) contains peak abundances in meltglass, nanodiamonds, microspherules, and charcoal.
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