Abstract
Abstract— Zagami and Nakhla are achondrites and belong to the Shergotty‐Nakhla‐Chassigny (SNC) meteorite group. It is generally accepted that Mars is their parent body. Mineralogical and chemical analyses have revealed that the major mineral phases of these two meteorites are pyroxene, olivine, maskelynite, and plagioclase. In this work, near‐infrared biconical reflectance measurements were performed on sawed surfaces of chips from Zagami and Nakhla. Spectra obtained with an analytical spot diameter on the order of the mineral grain size reflect the heterogeneous distribution of different mineral phases. The characteristic absorption bands of the pyroxenes are numerically evaluated in terms of the modified Gaussian model. Spectra with overlapping absorption features are resolved into the basic absorption bands. From these results, it can be estimated what kind of clinopyroxenes belong to the investigated mineral assemblages. As a result, the major clinopyroxene phase in Nakhla is Ca‐rich augite, whereas in Zagami both Ca‐rich and Ca‐poor pyroxenes are present. By means of such a procedure, laboratory spectra of minerals become more informative and may help in discussing Martian remote sensing data in the near‐infrared region.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
