After seeing the images with “A Riot of Over 300 Regmaglypts!” I am prompted to share with Listees my thoughts on the term “regmaglypt.”
Buchwald (1) calls regmaglypts “a specific hallmark of an iron meteorite,” a term introduced by Berwerth in 1909. Also known as “thumb prints,” Buchwald goes on to state: “Regmaglypts are thumb-like pits carved into the surfaces by turbulent supersonic airstreams during the atmospheric flight.” I beg to differ and offer another interpretation, based on my theory (2) that nickel-irons and stony-irons are cast materials solidified under microgravity conditions. This means that surface energy dominates in the liquid state and during solidification until the mass is solid. Observation of nickel-iron meteorite surface features commonly called regmaglypts indicates that these features can be separated into two different phenomena: flow lines and thumb prints. Flow lines are surface features related to ablation melting during passage through the Earth’s atmosphere. Thumb prints have 2 components: (a) angular, linear regions and (b) indentations. I propose that each was generated by a different mechanism. (a) Angular, linear boundaries: Observe a mass of soap bubbles, a system that tries to minimize surface energy. Interior bubbles will have polyhedral shapes, producing linear boundaries between bubbles. (3, 4). (b) Indentations: Metals shrink on cooling. What do YOU think?! Phyllis Budka References 1. Buchwald, V.N., Handbook of Iron Meteorites, Vol. 1, p. 47, Univ. of California Press, 1975 2. See my website at http://meteormetals.com/ 3. Boys, C.V., Soap Bubbles, 1959 Edition by Dover Publications of the original 1911 book. 4. Isenberg, Cyril, “The Science of Soap Films and Soap Bubbles,” 1978, Tieto Ltd ______________________________________________ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
