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Apollo 17 Orange Glass Pyroclastic Deposit. Six Major Dark Mantle Deposits. Taurus-Littrow Deposit at Apollo 17. Apollo 17 Site. Apollo 17 Orange Glass. It consists of orange glass spheres (average of 40 microns in diameter), black spheres (quench crystallized) and some mineral debris.
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Apollo 17 Orange Glass Pyroclastic Deposit Six Major Dark Mantle Deposits Taurus-Littrow Deposit at Apollo 17 Apollo 17 Site COSMOCHEMISTRY iLLUSTRATED
Apollo 17 Orange Glass It consists of orange glass spheres (average of 40 microns in diameter), black spheres (quench crystallized) and some mineral debris. The Apollo 17 orange glass deposit was sampled in place, though it was overturned by an impact event 30 My ago. COSMOCHEMISTRY iLLUSTRATED
1 m Enrichments in Volatile Elements in Pyroclastic glass deposits • Surfaces of pyroclastic glasses enriched inZn, Cd, Hg, Pb, Cu, F, Cl compared to other lunar materials • Probably were in gas phase associated with eruption • Implies volatile reservoirs inside Moon Surface coatings enriched in volatile elements; largest crystals are NaCl, mounds enriched in Zn, S, etc. Image courtesy of David McKay COSMOCHEMISTRY iLLUSTRATED
H2O in Volcanic Glass Ion microprobe measurements show that the orange and green glasses returned by Apollo contain H2O, along with other volatiles. Saal et al. (2008) Initial concentration estimated at 70-745 ppm. N-MORB glasses:~750-2000 ppm COSMOCHEMISTRY iLLUSTRATED