Evidence for Subsolidus Metasomatism in the Eucrite Parent BodyThe eucrite parent body (4Vesta) was continuously and rapidy resurfaced by basaltic lavas that formed the non-cumulate eucrites. Ophitic and variolitic textures have been preserved even though eucrites exhibit varying degrees of equilibration based on the extent of thermal metamorphism. Types range from least metamorphosed (type 1) to most metamorphosed (type 7) based in part on the interpretation of textures and compositional zoning profiles within pigeonitic pyroxenes. To provide constraints on the source and duration of the heating event responsible for metamorphism we have investigated primary and secondary textural and compositional relations in noncumulate eucrites with emphasis on subsolidus textures developed in pyroxenes. We have studied examples of most metamorphic types including Pasamonte (type 2) Stannern (4), Nuevo Laredo (4), Juvinas (5), Lakangaon (5), Millbillillie (6), Palo Blanco Creek (7), Jonzac (7), Haraiya (7), along with the cumulate eucrites Moama and Moore County.
Document ID
20040062444
Acquisition Source
Johnson Space Center
Document Type
Conference Paper
Authors
McCallum, I. Stewart (Washington Univ. Seattle, WA, United States)
Schwartz, Jeffrey M. (Washington Univ. Seattle, WA, United States)
Mullen, Emily K. (Washington Univ. Seattle, WA, United States)
Date Acquired
August 21, 2013
Publication Date
January 1, 2004
Publication Information
Publication: Lunar and Planetary Science XXXV: Achondrite Mishmash