Figure F5. Photomicrograph in plane-polarized light of Sample 187-1163A-3R-2 (Piece 10; see "Site 1163 Thin Sections"), showing a plagioclase sheaf quench texture and skeletal plagioclase in the groundmass of aphyric basalt (Unit 2). Notice the Fe oxyhydroxide staining along groundmass plagioclase (lower right corner) and the replacement of groundmass mesostasis by clay and Fe oxyhydroxide (lower left corner).