Plate 3. Photomicrographs. 1. Planar-wavy lamina with clastic texture (lower part of picture) is overlain by dark, matrix-rich lamina with detrital gypsum. Lenticular crystals are present in both laminae. Section 161-975B-33X-CC, 15-19 cm. Scale bar is 0.1 mm. 2. Coarse, interlocking crystals of gypsum in lower half of picture are the uppermost part of a planar-cumulus lamina overlain by a dark, matrix lamina with detrital gypsum. Section 975B-33X-CC, 22-27 cm. Scale bar is 0.1 mm. 3. Large intercrystalline pores in coarsely crystalline gypsum pinch-and-swell structure. Section 975B-34X-1, 26-30 cm. Scale bar is 0.1 mm. 4. Sample split along matrix-rich seam producing large epoxy-filled fracture seen in upper part of photograph. Fine lamination and detrital grains within the matrix-rich drape (left) interfinger and cover coarse, interlocking gypsum crystals in pinch-and-swell structure (right). For clarification, see core photograph in Figure 7. Section 975B-34X-1, 26-30 cm. Scale bar is 0.2 mm.

Plate 3. Photomicrographs. 1. Planar-wavy lamina with clastic texture (lower part of picture) is overlain by dark, matrix-rich lamina with detrital gypsum. Lenticular crystals are present in both laminae. Section 161-975B-33X-CC, 15-19 cm. Scale bar is 0.1 mm. 2. Coarse, interlocking crystals of gypsum in lower half of picture are the uppermost part of a planar-cumulus lamina overlain by a dark, matrix lamina with detrital gypsum. Section 975B-33X-CC, 22-27 cm. Scale bar is 0.1 mm. 3. Large intercrystalline pores in coarsely crystalline gypsum pinch-and-swell structure. Section 975B-34X-1, 26-30 cm. Scale bar is 0.1 mm. 4. Sample split along matrix-rich seam producing large epoxy-filled fracture seen in upper part of photograph. Fine lamination and detrital grains within the matrix-rich drape (left) interfinger and cover coarse, interlocking gypsum crystals in pinch-and-swell structure (right). For clarification, see core photograph in Figure 7. Section 975B-34X-1, 26-30 cm. Scale bar is 0.2 mm. Click on image for enlargement.