Mathematics – Logic
Scientific paper
Dec 2009
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009agufm.p23b1253n&link_type=abstract
American Geophysical Union, Fall Meeting 2009, abstract #P23B-1253
Mathematics
Logic
[5464] Planetary Sciences: Solid Surface Planets / Remote Sensing, [5470] Planetary Sciences: Solid Surface Planets / Surface Materials And Properties, [6250] Planetary Sciences: Solar System Objects / Moon
Scientific paper
The youngest, best-preserved and unfilled multi-ringed impact basin on the Moon (Orientale; ~920 km diameter) provides a laboratory for studying the nature of basin interior deposits and ring formation. We report here on the acquisition of new Moon Mineralogy Mapper (M3) data related to several key questions: Nature of Basin Ejecta (Hevelius Formation-HF): This unit is characterized by homogeneous and well-mixed assemblages of processed feldspathic breccias (with small amounts of low-Ca pyroxene) typical of the upper-crustal megaregolith layer. Origin of Montes Rook Formation: This unit, occurring between the Cordillera ring (CR) basin rim and the Outer Rook (OR) ring, shows characteristics similar to the Hevelius, but is not as well mixed and shows some shocked anorthositic blocks; this supports the interpretation that it is composed of modified proximal basin ejecta. Nature of Basin Rings: The CR consists of unweathered feldspathic breccias, similar to the HF; the OR consists of distinctively more-crystalline blocks of norite-anorthosite and shocked anorthosite and is not well mixed; the Inner Rook (IR) mountains consist at least locally of pure anorthosite with discrete zones that are unshocked and crystalline. Origin of Maunder Formation (MF): The MF is composed of two facies (outer corrugated and inner plains) and lies within the OR; MF is dominated by anorthositic lithologies with very little mafic component and these characteristics support the interpretation that the MF is composed of basin-related impact melt. Origin of Rings: These observations support the interpretation that the CR is a fault scarp in ejecta and megaregolith, that the OR is a close approximation to the basin rim, and that the IR is an uplifted part of the less-shocked basin floor. Basin Depth of Sampling: These data favor the interpretation that the Orientale basin sampling depth was largely confined to the upper crust; the mineralogy of the central peaks of the post-Orientale 55 km diameter Maunder crater, located in the basin interior depression inward of the IR, are somewhat enriched in low-Ca pyroxene and may have sampled lower crust, but apparently not mantle. Nature of Mare Fill: A variety of volcanic landforms are seen on the basin floor. The mineralogy of the maria indicates at least two major phases of mare fill in Mare Orientale, and later distinctive stages in Lacus Veris and Lacus Autumni along the base of the OR and CR in the northeast part of the basin; numerous exposures of mare basalts are contaminated in part by material from surrounding basin massifs and Maunder crater ejecta, but basalts show a range Ti-contents from relatively low to relatively high. Together, these data are revealing the structural, morphological and compositional characteristics of a very well-preserved large impact basin, the location, mineralogy and age of early mare fill stages, and the relationships of impact basin formation to mare basalt volcanism.
Dickson James
Fassett Caleb
Head James W.
Isaacson Peter
Klima Rachel
No associations
LandOfFree
Orientale Impact Basin: New Insights into Formation and Evolution from Chandrayaan-1 Moon Mineralogy Mapper 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 Orientale Impact Basin: New Insights into Formation and Evolution from Chandrayaan-1 Moon Mineralogy Mapper, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Orientale Impact Basin: New Insights into Formation and Evolution from Chandrayaan-1 Moon Mineralogy Mapper will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1769173