b. Thick section photographed in
a. Sample location.
c. Thin sections photographed between crossed polarizers (top) and in
natural light (bottom).
Figure 27. Sample M13, taken from the deck in warm weather, near 3C
(scales in millimeters). Note the mixture of small crystals, and large, irregu-
lar crystals in the thin sections. Approximately 50% of the sample consisted
of pores filled with brine or air.