Precursor lithologies and metamorphic history of granulitic breccias from North Ray crater, Station 11, Apollo 16

Details Precursor lithologies and metamorphic history of granulitic breccias from North Ray crater, Station 11, Apollo 16 Precursor lithologies and metamorphic history of granulitic breccias from North Ray crater, Station 11, Apollo 16

Jan 1987

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1987gecoa..51..131o&link_type=abstract

Geochimica et Cosmochimica Acta (ISSN 0016-7037), vol. 51, Jan. 1987, p. 131-142. DFG-supported research.

Computer Science

Sound

1

Breccia, Ejecta, Lithology, Lunar Craters, Satellite Sounding, Annealing, Apollo 16 Flight, Chemical Composition, Petrography, Photomicrographs, Rare Earth Elements, Moon, Lithology, Metamorphism, Breccias, North Ray, Apollo 16, Ejecta, Station 11, Samples, Lunar, Parent Material, Analysis, Composition, Age, Chemistry, 67485, 67488, 67615, 67749, 67947, 67566, Matrix, Clasts, Orign, Source, Comparisons, Minor Elements, Major Elements, Granulites, Recrystallization, Texture, Trace Elements, Surface, Heating,

Scientific paper

Two distinctly different types of granulitic breccias in the ejecta of North Ray crater, Station 11, Apollo 16 have been analyzed for their modal and chemical composition. Samples 67485, 67488, 67615, 67749, 67947, and 67566 are characterized by a fine-grained granoblastic to poikiloblastic matrix and abundant lithic and mineral clasts predominantly derived from ferroan anorthosites. The mineral clasts in sample 67566 were derived from ferroan anorthosites and Mg-rich lithologies. The fine-grained granulitic breccias are compositionally almost identical to the feldspathic microporphyritic melt breccias (fmmbs) of Station 11, Apollo 16 which are older than, and therefore are possible precursors of, the fine-grained granulitic breccias. The second type of granulitic lithology (67746) is medium-grained, anorthositic-noritic in composition, and contains well equilibrated minerals derived from Mg-rich rocks. The precursors of both granulitic lithologies were KREEP-free and according to their Ir/Au ratio were old lunar highland rocks. A comparison of major, minor, and trace element contents shows that the two types of granulites are unrelated. The different recrystallization textures of the two types of granulitic lithologies imply different metamorphic histories. Metamorphism of the fine-grained granulitic breccias occurred near the lunar surface and the heat source was probably a superheated impact melt. The texture and degree of equilibration in the minerals of 67746 require a much more intense metamorphism with slow cooling. Metamorphism of lunar rocks and breccias was a wide-spread process that occurred several times in lunar history.

Affiliated with

Also associated with

No associations

Rating

Precursor lithologies and metamorphic history of granulitic breccias from North Ray crater, Station 11, Apollo 16 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 Precursor lithologies and metamorphic history of granulitic breccias from North Ray crater, Station 11, Apollo 16, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Precursor lithologies and metamorphic history of granulitic breccias from North Ray crater, Station 11, Apollo 16 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1623543