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Typical broken fulgurite sections. Fulgurites (from Latin fulgur 'lightning' and -ite), commonly called "fossilized lightning", are natural tubes, clumps, or masses of sintered, vitrified, or fused soil, sand, rock, organic debris and other sediments that sometimes form when lightning discharges into ground.
Petrified Forest National Park is a national park of the United States in Navajo and Apache counties in northeastern Arizona.Named for its large deposits of petrified wood, the park covers about 346 square miles (900 square kilometers), encompassing semi-desert shrub steppe as well as highly eroded and colorful badlands.
The name of the park gives it away: Most of the fossils you'll see at Petrified Forest are of exquisite petrified wood from the Triassic period over 200 million years ago.
The Aztec Sandstone is made up of two units. The lower resistant sandstone unit (100 metres (330 ft) thick) is tan to off-white in outcrops but pinkish in fresh exposures. Cross-bedded lenses can easily be observed. Frosted and pitted quartz grains well-cemented by silica are described by Evans in 1958 and 1971.
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide).The atoms are linked in a continuous framework of SiO 4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO 2.
Glaciation of the southern hemisphere raised and lowered sea levels in Arizona, creating the ledge and slope topography common in the Grand Canyon, Sedona and Monument Valley, with alternating layers of siltstone, limestone, sandstone, dolomite and shale. The Kaibab Limestone is a famous formation from this time, covering much of northern ...
Quartzite can have a grainy, glassy, sandpaper-like surface. Quartzite is a hard, non-foliated metamorphic rock which was originally pure quartz sandstone. [1] [2] Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts.
Almost 12 years ago, a pilot flying a small plane over the desert in Arizona spotted something she would never forget. Pez Owen told NPR that when she noticed white crosses on the ground, she and ...