Other
Scientific paper
Jul 1994
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994metic..29q.481k&link_type=abstract
Meteoritics (ISSN 0026-1114), vol. 29, no. 4, p. 481
Other
3
Chondrites, Gas-Solid Interactions, Mineralogy, Nebulae, Petrology, Lithology, Pressure Effects, Temperature Effects, Vapor Pressure
Scientific paper
We wish to draw attention to a major controversy that has arisen in the area of CM-chondrite petrology. The problem is important because its resolution will have profound implications for ideas concerning nebular dynamics, gas-solid interactions in the nebula, and accretionary processes in the nebula, among other issues. On the one hand, cogent arguments have been presented that 'accretionary dust mantles,' were formed in the solar nebula prior to accretion of the CM parent asteroid(s). On the other hand, no-less-powerful arguments have been advanced that a significant fraction of the CM lithology is secondary, produced by aqueous alteration in the near-surface regions of an asteroid-sized object. Because most, if not all, CM chondrites are breccias, these two views could coexist harmoniously, were it not for the fact that some of the coarse-grained lithologies surrounded by 'accretion dust mantles' are themselves of apparently secondary origin. Such an observation must clearly force a reassessment of one or both of the present schools of thought. Our objective here is to stimulate such a reassessment. Four possible resolutions of this conflict may be postulated. First, perhaps nature found a way of permitting such secondary alteration to take place in the nebula. Second, maybe dust mantles could form in a regolith, rather than a nebular, environment. Third, it is possible that dust mantles around secondary lithologies are different from those around primary lithologies. Finally, perhaps formation of CM chondrites involved a more complex sequence of events than visualized so far, so that some apparently 'primary' processes postdated certain 'secondary' processes.
Bunch Ted E.
Kerridge John F.
McSween Harry Y. Jr.
No associations
LandOfFree
Petrologic evolution of CM chondrites: The difficulty of discriminating between nebular and parent-body effects 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 Petrologic evolution of CM chondrites: The difficulty of discriminating between nebular and parent-body effects, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Petrologic evolution of CM chondrites: The difficulty of discriminating between nebular and parent-body effects will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-822127