A coordinated spectral, mineralogical, and compositional study of ordinary chondrites

Surface composition and taxonomic classification of a group of near-Earth and Mars-crossing asteroids

“…Within the error bars this asteroid is classified as a S(IV) in the system of Gaffey et al (1993). Using the equations derived by Dunn et al (2010) we determined that the olivine and pyroxene chemistries are Fa 31 (Fo 69 ) and Fs 25 , respectively. These values are consistent with those derived for LL ordinary chondrites by Dunn et al (2010), which give a range of Fa Sanchez et al (2012).…”

“…The dashed curve indicates the location of the olivine-orthopyroxene mixing line (Cloutis et al, 1986). The horizontal lines represent the approximate boundaries for ordinary chondrites found by Dunn et al (2010).…”

“…The mafic silicate compositions of these objects were determined using the equations derived by Dunn et al (2010). With these equations it is possible to determine the molar contents of fayalite (Fa) in olivine and ferrosilite (Fs) in pyroxene in olivine-orthopyroxene assemblages.…”

“…With these equations it is possible to determine the molar contents of fayalite (Fa) in olivine and ferrosilite (Fs) in pyroxene in olivine-orthopyroxene assemblages. In addition, the mineral abundances (ol/(ol + px)) were calculated from the BAR values using the relationship found by Dunn et al (2010). This relationship was obtained from the analysis of ordinary chondrites and therefore can be applied to asteroids with similar mineralogies.…”

“…Using the equations derived by Dunn et al (2010) we determined that the olivine and pyroxene chemistries are Fa 31 (Fo 69 ) and Fs 25 , respectively. These values are consistent with those derived for LL ordinary chondrites by Dunn et al (2010), which give a range of Fa Sanchez et al (2012). Open triangles represent measured band centers for orthopyroxenes from Adams (1974), open circles correspond to measured band centers for clinopyroxenes from Cloutis and Gaffey (1991).…”