Photograph of a desert landscape at the mouth of Canyon Diablo near Leupp, Arizona, in 1913. Permian rocks display ripple marks. Photo 720 from Herbert E. Gregory Book 6: Navajo, 1913
Photograph of a dry wash and Permian cliffs capped by Shinarump strata in Bonito [Blue] Canyon, nort...
Photograph of Upper Permian rock exposed in Bonito Creek Canyon [now Blue Canyon] near Fort Defian...
Photograph of Navajo sandstone outcrops in the desert near Tuba City, Arizona, in 1914. Photo 950 ...
Photograph of a desert landscape at the mouth of Canyon Diablo near Leupp, Arizona, in 1913. Permia...
Photograph of a desert landscape near Leupp, Arizona, in 1913. Permian rocks display ripple marks. ...
Photograph of a desert landscape at the mouth of Canyon Diablo near Leupp, Arizona, in 1913. Permia...
Photograph of wind-carved Permian rock two miles above Tolchaco, Arizona, in 1913. Photo 729 from H...
Photograph of exposed Upper Permian rock in the desert near Holbrook, Arizona, in 1913. Photo 712 f...
Photograph of Canyon Diablo near Leupp, Colorado, looking north in 1913. Photo 723 from Herbert E. ...
Photograph by K. C. Heald showing ripple marks and mud cracks in La Plata or Dolores rock six miles ...
Photograph of a wind-swept sandstone landscape in the desert near Tuba City, Arizona, in 1914. Phot...
Photograph of exposed Permian, Shinarump, and Dolores rock near Tucker Spring near Winslow, Arizona,...
Photograph of Upper Permian rock exposed in Bonito Creek Canyon [now Blue Canyon] near Fort Defian...
Photograph of a butte of Permian rock near Holbrook, Arizona, in 1913. Photo 716 from Herbert E. Gr...
Photograph of a dry wash and Permian cliffs capped by Shinarump strata in Bonito [Blue] Canyon, nort...
Photograph of Upper Permian rock exposed in Bonito Creek Canyon [now Blue Canyon] near Fort Defian...
Photograph of Navajo sandstone outcrops in the desert near Tuba City, Arizona, in 1914. Photo 950 ...
Photograph of a desert landscape at the mouth of Canyon Diablo near Leupp, Arizona, in 1913. Permia...
Photograph of a desert landscape near Leupp, Arizona, in 1913. Permian rocks display ripple marks. ...
Photograph of a desert landscape at the mouth of Canyon Diablo near Leupp, Arizona, in 1913. Permia...
Photograph of wind-carved Permian rock two miles above Tolchaco, Arizona, in 1913. Photo 729 from H...
Photograph of exposed Upper Permian rock in the desert near Holbrook, Arizona, in 1913. Photo 712 f...
Photograph of Canyon Diablo near Leupp, Colorado, looking north in 1913. Photo 723 from Herbert E. ...
Photograph by K. C. Heald showing ripple marks and mud cracks in La Plata or Dolores rock six miles ...
Photograph of a wind-swept sandstone landscape in the desert near Tuba City, Arizona, in 1914. Phot...
Photograph of exposed Permian, Shinarump, and Dolores rock near Tucker Spring near Winslow, Arizona,...
Photograph of Upper Permian rock exposed in Bonito Creek Canyon [now Blue Canyon] near Fort Defian...
Photograph of a butte of Permian rock near Holbrook, Arizona, in 1913. Photo 716 from Herbert E. Gr...
Photograph of a dry wash and Permian cliffs capped by Shinarump strata in Bonito [Blue] Canyon, nort...
Photograph of Upper Permian rock exposed in Bonito Creek Canyon [now Blue Canyon] near Fort Defian...
Photograph of Navajo sandstone outcrops in the desert near Tuba City, Arizona, in 1914. Photo 950 ...