The Petrified Forest sits in the badlands of a dry, high desert, but its presence has everything to do with the action of water. Around 225 million years ago, in the late Triassic, mighty floods washed logs into low swales, burying them in sediment that later hardened to rock—the Chinle formation. Over time, wood cells filled with silica that had been dissolved in hot, mineralized water, ultimately replacing all the wood. The silica, stained with mineral oxides, hardened into casts matching the size, shape and general structure of the original logs—right down to hollows, knots and even the shape and texture of bark. Undisturbed for over 100 million more years, these mineral infusions sat underground. Crustal uplift of the Colorado Plateau region increased the area’s elevation and steepened water-flow gradients. These petrified logs had become much harder than the surrounding stone, and stayed behind as the host rock crumbled and washed away. The same geologic-uplift process ultimately was responsible both for this scene and the Grand Canyon, a hundred miles away.
9 SSE Adamana AZ (1 Aug 17) Looking SE
34.864, -109.7904
Petrified Forest Landscape
The Petrified Forest sits in the badlands of a dry, high desert, but its presence has everything to do with the action of water. Around 225 million years ago, in the late Triassic, mighty floods washed logs into low swales, burying them in sediment that later hardened to rock—the Chinle formation. Over time, wood cells filled with silica that had been dissolved in hot, mineralized water, ultimately replacing all the wood. The silica, stained with mineral oxides, hardened into casts matching the size, shape and general structure of the original logs—right down to hollows, knots and even the shape and texture of bark. Undisturbed for over 100 million more years, these mineral infusions sat underground. Crustal uplift of the Colorado Plateau region increased the area’s elevation and steepened water-flow gradients. These petrified logs had become much harder than the surrounding stone, and stayed behind as the host rock crumbled and washed away. The same geologic-uplift process ultimately was responsible both for this scene and the Grand Canyon, a hundred miles away.
9 SSE Adamana AZ (1 Aug 17) Looking SE
34.864, -109.7904