Carbonaceous shale alternates between br. gray and red gray to 195cm. becoming increasingly carbonaceous and finely lignite at 235 cm. 13 35 Lignite 14 215. red, gray chippy shale (25 cm) interbedded w/ br. ripple bedded sand with carbonaceous lam, sand is v fg clayey, Unit consists of alt beds of this shale and this sand 20 to 75cm in thickness. 15 1020. = Unit 12 IN Sec. 8421 Lignite, Petrified Forest Lignite ? with soil lenses up to 30cm thick and standing v fallen petrified stumps, -> picture of forest floor at 495 < major forest floor in fresh water ls. occurs in lenses at 455