Plate P1. Photomicrographs illustrating sands and sandstones of the Woodlark rift. 5. A medium-grained feldspathic sand containing fresh angular detrital grains of plagioclase (commonly zoned), biotite, hornblende, and foraminifer tests (Sample 180-1115C-10R-1, 5-7 cm [369.55 mbsf]) (cross-polarized light).