Ranger Robb: Abajo Mountains quartz diorite porphyry, granodiorite porphyry, Cave Spring, Needles District Canyonlands NP, Utah
Ranger Robb: Defferential erosion between harder Sanstone and softer Silt/mudstone of the Cedar Mesa Formation, , Cave Spring, Needles District Canyonlands NP, Utah
Ranger Robb: Differential erosion in Cedar Mesa Sandston, near Cave Spring, Needles District Canyonlands NP, Utah
Ranger Robb: Seep near Cave Spring, Needles District Canyonlands NP, Utah
Ranger Robb: Cave Spring, Needles District Canyonlands NP, Utah
Ranger Robb: Tephoni, Needles District, Canyonlands National Park, Utah