Plate P1. Photomicrographs illustrating sands and sandstones of the Woodlark rift. 6. Feldspathic sandstone with abundant detrital grains of feldspar, colorless vitric volcanic lithic fragments, biotite, and hornblende in a glass-rich matrix (Sample 180-1109D-3R-2, 148-149 cm [371.68 mbsf]) (plane-polarized light).