Slip and the clinoenstatite transformation as competing rate processes in enstatite
1971; American Geophysical Union; Volume: 76; Issue: 17 Linguagem: Inglês
10.1029/jb076i017p04011
ISSN2156-2202
AutoresC. B. Raleigh, S. H. Kirby, N. L. Carter, Hans G. Avé Lallemant,
Tópico(s)Geological and Geochemical Analysis
ResumoJournal of Geophysical Research (1896-1977)Volume 76, Issue 17 p. 4011-4022 Slip and the clinoenstatite transformation as competing rate processes in enstatite C. B. Raleigh, C. B. RaleighSearch for more papers by this authorS. H. Kirby, S. H. KirbySearch for more papers by this authorN. L. Carter, N. L. CarterSearch for more papers by this authorH. G. Avé Lallemant, H. G. Avé LallemantSearch for more papers by this author C. B. Raleigh, C. B. RaleighSearch for more papers by this authorS. H. Kirby, S. H. KirbySearch for more papers by this authorN. L. Carter, N. L. CarterSearch for more papers by this authorH. G. Avé Lallemant, H. G. Avé LallemantSearch for more papers by this author First published: 10 June 1971 https://doi.org/10.1029/JB076i017p04011Citations: 141AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Abstract Previous experimental deformation of orthorhombic enstatite at temperatures from 200° to 1000°C has produced clinoenstatite; yet, the natural occurrences of clinoenstatite in deformed rocks is extremely rare. The present experiments were conducted on the premise that transformation to clinoenstatite and slip in orthoenstatite are competing rate-controlled deformation processes, with slip having the higher activation energy. The results show that, at strain rates of 10−3 to 10−7 sec−1, slip occurs in orthoenstatite without transformation to clinoenstatite at temperatures above 1300° to about 1000°C, respectively. Parameters of the creep equations for the two different flow processes were determined empirically using stress-relaxation and temperature-differential creep tests. The boundary between slip in orthoenstatite and transformation to clinoenstatite calculated theoretically from the flow laws agrees well with the experimental boundary. Extrapolation to geologically reasonable strain rates suggests that, above a temperature between 450° and 650°C, clinoenstatite will not form in natural deformation of orthoenstatite except where strain rates are abnormally high. 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