Transantarctic Mountain microtektites: Geochemical affinity with Australasian microtektites

HED-like cosmic spherules from the Transantarctic Mountains, Antarctica: Major and trace element abundances and oxygen isotopic compositions

“…below detection limit) and low SiO 2 contents (<52 wt.%). Thus, they differ from the terrestrial glass particles found in the micrometeorite traps, volcanic glass shards (Na 2 O >3 wt.%; Curzio et al, 2008) or microtektites (SiO 2 >59 wt.%; Folco et al, 2009), and from ablation debris spherules (Na 2 O $2 wt.%; Genge and Grady, 1999;van Ginneken et al, 2010;Cordier et al, 2011c). Therefore, all the studied particles can be classified as cosmic spherules.…”

Vestoid cosmic spherules from the South Pole Water Well and Transantarctic Mountains (Antarctica): A major and trace element study

“…SP29-82 and 3.5-7 have much lower alkali metal contents (Na 2 O + K 2 O < 0.12 wt.%) than terrestrial igneous rocks (Na 2 O + K 2 O > 2 wt.%; Sun and McDonough, 1989). These two particles also have lower SiO 2 contents (SiO 2 < 50 wt.%, Table 2) than microtektites (SiO 2 > 59 wt.%, Folco et al, 2009). Thus, the two newly discovered differentiated particles SP29-82 and 3.5-7 are not terrestrial and can be classified as differentiated CS.…”

Fission track age of Transantarctic Mountain microtektites

“…For the fission track dating of Transantarctic Mountain microtektites we selected 120 microtektites in the 400-800 lm size range from micrometeorite trap #20c at the top of Miller Butte (72°42.078 0 S, 160°14.333 0 E; 2600 above sea level; see Folco et al (2009) for further details). The selected microtektites are pale yellow and transparent (Fig.…”

“…Microtektites (microscopic impact glass spheroids) were recently discovered on the Victoria Land Transantarctic Mountains (Folco et al, , 2009). They were found trapped in the fine-grained local detritus accumulated in weathering pits, joints and fractures of the glacially eroded summits ($2600 m a.s.l.)…”

“…Based on petrographic, major and trace element compositions, Sr and Nd isotopic compositions and a poorly resolved, yet Quaternary, 40 Ar-39 Ar age of 0.76 ± 0.98 Ma, Folco et al (2008, 2009, 2010a suggested that Transantarctic Mountain microtektites most likely represent a major southern extension of the 0.76 ± 0.05 Ma old (Izett and Obradovich, 1992) Australasian tektite-microtektite strewn field. The large uncertainty in the 40 Ar-39 Ar age of Transantarctic Mountain microtektites is due to the presence of excess argon, their low K content and their relatively young age .…”