Relationship between positive CE anomaly and adsorbed water in Antarctic lunar meteorites

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

2

Scientific paper

Concentration of adsorbed water in single mineral grains of Antarctic lunar meteorites was determined with micro IR spectroscopy. A relationship was found between the mineral ability to adsorb water and the extent of Ce anomaly in REE pattern precisely determined by the isotope dilution method using a thermal ionization mass spectrometry. Aska(A)-881757, a lunar meteorite from the mare basalt without Ce anomaly, showed no trace of IR absorption due to adsorbed water. On the contrary, Yamato(Y)-791197-109, Y-86032-98, Y-86032-95, Y-791197- 115 and Y-82192-55A from the lunar highland exhibiting positive Ce anomaly showed IR absorption due to adsorbed water in some of their minerals. The detected water would be a terrestrial origin, because it was not structurally bound and easy to exchange judging from the spectral band shape. The contrast in concentration of adsorbed water between the lunar highland and the mare basalt derived from a difference in the density of micro fracture in mineral grain. Average concentrations of adsorbed water in the lunar highland meteorites were 3.8 mg/cm3 for pyroxene and olivine, and 1.7 mg/cm3 for plagioclase, respectively. This contrast between minerals is noteworthy because it has been known that Ce anomaly of pyroxene and olivine is larger than that of plagioclase both for Antarctic lunar meteorites and some lunar rocks. Furthermore, more adsorbed water was detected for minerals in meteorite exhibiting larger Ce anomaly. The present observations demonstrated that the extent of Ce anomaly correlated with the concentration of adsorbed water, which suggests that active mineral surface resulting in adsorption of water could be a trace of interaction forming Ce anomaly. Terrestrial weathering on Antarctica and REE fractionation on the Moon were discussed for possible origins of the Ce anomaly.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Relationship between positive CE anomaly and adsorbed water in Antarctic lunar meteorites does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Relationship between positive CE anomaly and adsorbed water in Antarctic lunar meteorites, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Relationship between positive CE anomaly and adsorbed water in Antarctic lunar meteorites will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1711755

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.