Evaluation of the sensitivity of reflectance ratios to mafic minerals in the lunar regolith

The 950/560-nm spectral ratio has been traditionally used as a qualitative indicator or lunar soil maturity because the 950-nm band falls within the major Fe(2+) mineral absorption bands near 1-micron characteristic of relatively immature crystalline surfaces. Since there are several other processes unrelated to maturation that may affect this ratio value, the 950/730-nm ratio has been evaluated as a potentially better measure of the relative 1-micron band strength. It is found that the 950/730-nm ratio appears to be much more sensitive to the 1-micron band depth, but it is believed that other unknown variables preclude using these single ratios to provide meaningful quantitative results at this time.