Trip to Arizona, January 7 - January 18, 2004

Petrified Forest National Park

Fossils exposed in the park are from Chinle Formation, Triassic Period

Scattered Wood

Giant Log, "Old Faithful"

Petrified Log Texture. Which minerals produce the colors?

The fossilized logs are from Araucarioxylon arizonicum, Woodworthia and Schilderia. All 3 species are now extinct.

Raven

The Tepees. Distinct white layers are sandstone, the cap is clay, dark layers have high carbon content, darker reds are iron-stained siltstone, reddish bases are hematite.

The Tepees. See the legend above.

Desert Freedom

Newspaper Rock. See detail below

Ancient Petroglyphs on the Newspaper Rock (dated from about 1000-1350 A.D.)

Painted Desert

Rainbow of colorful sediments

Back to Phoenix. I-40. San Francisco Peaks are on the horizon

Montezuma Well. Montezuma Well is a limestone sink formed long ago by the collapse of an immense underground cavern.

Phoenix Area. Desert Botanical Garden

Aloe

Brain Cactus

Saguaro Cactus

Saguaro Cactus

Cottontail :)

Papago Mountain. The red rock (iron oxide-hematite) of the mountain was formed 6 to 15 million years ago

Phoenix Area. Camelback Mountain

Tilted layers of Tertiary red rocks (Camel's Head Formation) lies on a much larger and higher mass of Precambrian granite. Summit elevation is 2704 ft (824 m) -- the peak rises about 1600 ft (488 m) above the elevation of downtown Phoenix.