Product Code Database
The Yavapai orogeny was an orogeny (mountain-building) event in what is now the Southwestern United States that occurred between 1710 and 1680 million years ago (Mya), in the Statherian Period of the Paleoproterozoic. Recorded in the rocks of New Mexico and Arizona, it is interpreted as the collision of the 1800-1700 Mya age Yavapai island arc terrane with the proto-North American continent. This was the first in a series of orogenies within a long-lived convergent boundary along southern Laurentia that ended with the ca. 1200–1000 Mya Grenville orogeny during the final assembly of the supercontinent Rodinia, which ended an 800-million-year episode of convergent boundary tectonism.
Some of the orogens were accompanied by slab rollback. This created short-lived Back-arc basin at 1700 and 1650 Mya that accumulated sand and high-silica volcanic debris to form Paleoproterozoic quartzite-rhyolite successions. Subsequent convergent tectonics closed the basins and Thrust fault imbricated the successions. That is, faulted blocks of rock were stacked atop each other like shingles on a roof.
The northeast-trending provinces are truncated by Neoproterozoic passive margins that indicate the orogenic system once extended much further. This is part of the basis for the AUSWUS reconstruction of Rodinia, which places Australia adjacent to the southwestern US from 1800 to 1000 Mya. Other supporting evidence includes correspondence of 1450 and 1000 Ga paleomagnetic poles between Australia and Laurentia. The northeastern extension of the orogenic belt would then correspond to the Gothian orogeny in Baltica and the southwestern extension to the Albany-Fraser orogeny. However, the placement of Australia has been disputed on the basis of paleomagnetic data. The SWEAT reconstruction places East Antarctica on the southwest extension of the Yavapai Province.
The Yavapai Province was named for the Yavapai Supergroup in central Arizona. It extends from Arizona to Colorado south of the Cheyenne belt, then northeastward to the mid-continent region. The southern boundary is somewhat poorly defined, possibly because it corresponds to a shallow relic subduction zone, but runs roughly along the Jemez Lineament. Individual island arc terranes accreted to Laurentia during the Yavapai Orogeny include the Elves Chasm block in the Grand Canyon, Green Mountain, Dubois-Cochetopa, Irving Formation, Moppin Complex-Gold Hill, and Ash Creek-Payson Granite. The latter includes the Payson Ophiolite. Quartzite-rhyolite successions associated with extensional basins include the Vadito Group and Hondo Group in New Mexico and the Mazatzal Group in Arizona, deposited during the transition from the Yavapai to the Mazatzal orogens at 1700 Mya. The extensional basin in which the Mazatzal Group was deposited lasted about 30 Ma, from the Payson Ophiolite at 1730 Mya to the Mazatzal Peak Quartzite sometime after 1700 Mya.
A number of regional orogenies fall within the time span of the Yavapai orogeny and are regarded as parts of the overall orogenic system. These include the Ivanpah orogeny (1710–1680 Mya) in the New York Mountains area; the Central Plains orogeny in the mid-continent; the Medicine Bow orogeny at 1708–1750 Mya that produced the Cheyenne belt, the Colorado province or Colorado orogeny at 1780–1700 Mya.
|
|
