(sl) The tektite chemistry is unlike that of the black glass (obsidian, see Spec
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(sl) The tektite chemistry is unlike that of the black glass (obsidian, see Specimen Ci en from volcanoes and are not associated with any known volcanoes of equivalent a have not been found on the moon. Tektites are characterised by high silicon, aluminium, iron, ) erupted ge, Tektites magnesium, calcium, potassium, soudium, titanium, manganese and contain minor water. Are tektites of lunar origin and give reasons for your answer? (xili) Tektites are found in Haiti (64.5 Ma), SE USA (35 Ma), Crechoslovakia (14.7 Ma), Ivory Coast (1.7 a known major impact? If yes, which one? Ma) and SE Asia-Australia (0.8 Ma). Does any one of these ages correlate with sions of Fe-Ni alloys. Fe sulphides and Fe phosphides are found in tektites What is the origin of this material? (xv) The moon and meteorites are composed of lo w-silica minerals. Tektites contain rare t pure silica glass (lechatelierite) and very rare crystals of coesite. Coesite is an extremely high-pressure variety of silica. What is the origin of the lechatelierite and co esite? (xvi) O age of the parental material of the tektite glass. The ages are: SE USA tektites (650 Ma). Czechoslovak tektites (900 Ma). Ivory Coast tektites (1900 Ma) and SE Asia-Australian tektites (1150 Ma). Why is this data the final nail in the coffin for the lunar origin of tektites? ne geochemical technique using the isotopes of neodymium and samarium can trace the (xviii) Explain why tektites cannot be found in ancient rocks (generally older than 64.5 Ma) on planet Earth?Explanation / Answer
(xii) The tektites cannot have originated outside the Earth-Moon system and must have been launched either by volcanism or by an impact. There are four possibilities in which two can be disposed of. This is because Earth volcanism is not nearly powerful enough to cover the known strewnfields. Also, lunar impact because the part of the moon's surface which is covered with rock is not large enough to make this a viable alternative. The other possibilities left are Earth impact and lunar volcanism. Earth impact fails because it is in direct contradiction to the principles of glass science. This is because aerodynamic principle excludes the possibility of launching a liquid mass at certain velocities through the atmosphere, and because the external form and internal structure require leisurely formation in a low-stress environment, followed much later by ejection after the glass has cooled. From these, we can conclude that tektites are formed from lunar volcanoes.
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