Weak fine granular structure, very friable.  3.41% organic carbon; 
5.9% clay; 18.8% silt; 75.3% sand.

Clay mineralogy: small vermiculite peak, and weak kaolinite, gibbsite and 
mica peaks.

Coarse mineralogy: 34% biotite, 24% quartz, 16% plagioclase feldspar, 10% 
muscovite, 8% garnet,, 2% potassic feldspar, 1% epidote, 1% rutile, 1% 
pyroxene, 1% zircon, 1% opaque, 1% weathered aggregate.

Spectral Description:  Superimposed on the typical broad water band are 
weak, sharp hydroxyl features near 2.71 and 2.76 microns with a very weak 
shoulder between them near 2.74 microns, accompanied by a band near 2.21 
microns with shortwavelength asymmetry in the near-infrared.  All these 
bands are typical of kaolinite.  Biotite and vermiculite display distinctive 
bands in the near-infrared that do not appear in this spectrum except as 
vague features that could as easily be noise, despite their greater abundance 
(especially biotite) in the soil.  This lack of spectral expression appears 
typical of these minerals.  On the other hand, despite its relatively low 
abundance, very weak absorption bands can just be discerned near 2.83 and 
2.91 microns due to gibbsite.  Like the previous soil (87P325), this sample 
contains abundant organic matter.  It too is quite dark and the H-C 
absorption bands near 3.41 and 3.50 microns are surprisingly weak.  These 
bands are accompanied by a weak, broad absorption band near 2.50 microns 
and the typical ramped reflectance peak near 6.70 microns.  Quartz 
combination tone bands appear near 4.47, 4.68, 5.01 and 5.33 microns.  
These quartz bands, especially the ones at longer wavelength, are subdued 
by the very strong, broad H-O-H bending vibration band associated with 
abundant organic matter, which completely eliminates the combination tone 
bands longward of 5.33 microns, contribution to the ramped peak near 6.70 
microns.  The quartz reststrahlen doublet between 7.7 and 9.7 microns peak 
superimposed on its long wavelength margin, which is difficult to assign.  
Normally, a peak near 9.25 microns is contributed by K-feldspar, but this 
mineral is not present in large enough amounts to account for the strength of 
this feature.  We attribute the 9.25 micron peak to plagioclase.  The weak 
bands near 9.64 and 9.87 microns can be accounted for by muscovite and 
biotite, respectively.  The very broad reflectance maximum between these 
peaks and the alpha quartz doublet near 12.6 microns is probably due to 
organic matter.
