X-ray diffraction characteristics of calcic plagioclase from eucrites as well as lunar highland and Archean anorthosites
Tagai, Tokuhei; Hoshi, Takeshi; Suzuki, Masaya
European Journal of Mineralogy Volume 10 Number 1 (1998), p. 125 - 132
published: Jan 26, 1998
manuscript accepted: Sep 22, 1997
manuscript received: Aug 23, 1996
ArtNo. ESP147051001012, Price: 29.00 €
Abstract X-ray intensity distributions of diffuse c-reflections were investigated in calcic plagioclases from different parageneses including eucrite (ALH85001, Moore County, Moama, Serra de Magé), lunar anorthosite (Lunar 76335) and terrestrial Archean anorthosite (BVL-105), thus representing various stages of crustal evolution in the early solar system. The profiles of the c-reflection were measured along directions parallel and normal to the diffuse streak, and the corresponding domain sizes were calculated from their FWHMs. Lunar highland anorthite shows the largest c-domain size, which indicates the slowest cooling rate among the studied specimens. The Moore County anorthite shows a very small domain size in spite of the plutonic texture, which may indicate reheating after the cumulate formation process.