Figure F50. Photomicrographs (both in cross-polarized light) showing sanidine xenocrysts (in various degrees of preservation), which are characteristic of basaltic Units 6-17. A. A sanidine xenocryst with a developing sieve texture around the rim (Sample 183-1139A-64R-1, 81-84 cm; Unit 7); a plagioclase phenocryst (fractured by later secondary alteration) is also shown. B. A highly resorbed sanidine xenocryst from Unit 13 (Sample 183-1139A-66R-7, 5-8 cm).