Using VSWIR microimaging spectroscopy to explore the mineralogical diversity of HED meteorites

Abstract

We use VSWIR microimaging spectroscopy to survey the spectral diversity of HED meteorites at 80-µm/pixel spatial scale. Our goal in this work is both to explore the emerging capabilities of microimaging VSWIR spectroscopy and to contribute to understanding the petrologic diversity of the HED suite and the evolution of Vesta. Using a combination of manual and automated hyperspectral classification techniques, we identify four major classes of materials based on VSWIR absorptions that include pyroxene, olivine, Febearing feldspars, and glass-bearing/featureless materials. Results show microimaging spectroscopy is an effective method for rapidly and non-destructively characterizing small compositional variations of meteorite samples and for locating rare phases for possible follow-up investigation. Future work will include incorporating SEM/EDS results to quantify sources of spectral variability and placing observations within a broader geologic framework of the differentiation and evolution of Vesta.

Can Formulas Derived From Pyroxenes and/or HEDs Be Used to Determine the Mineralogies of V‐Type Asteroids?

“…Pyroxene analyses coupled with spectral reflectance measurements should be done for more HEDs. One promising technique to do these types of analyses was explored by Fraeman et al (). They did visible‐short wavelength infrared imaging spectroscopy of HED fragments at 80 μm/pixel and plan to do spatially correlated scanning electron microscope/energy‐dispersive X‐ray spectroscopy to determine the mineralogy of every small area on the chip where a spectrum was obtained. Formulas from previous studies should be derived again if the fitting technique used to determine band centers is different at all in the new study.…”