Defiance uplift
Coordinates: 35 ° 51 ′ N , 109 ° 15 ′ W
The Defiance Uplift is an uplift in the border area of the US states Arizona and New Mexico in the center of the Colorado Plateau . It runs in north-south direction and has a length of over 150 km and a width of about 55 to 70 km. They created the Defiance Plateau with a maximum height of 2389 m.
geography
The name defiance comes from the former military base and today's settlement of the same name Fort Defiance , which in turn are named after the English word that means about to defend oneself . It was transferred to the plateau in 1916 and later to the uplift. Window Rock is south of Fort Defiance . On the Defiance Plateau itself, apart from these two places, there are only scattered Navajo settlements, on the edge of the uplift are Shiprock and Gallup on the eastern flank belonging to New Mexico, as well as Ganado , Chinle and Mexican Water in Arizona and in the west. In the valleys that limit the uplift, there are highways in the north of US 64 , which joins US 160 , in the east of US 666 , in the south of Interstate Highway 40 and in the west of US 191 . The only major crossing of the area is New Mexico State Route 264 , or Arizona State Route 264 , which runs in an east-west direction and crosses Window Rock.
All of the uplift lies in the Navajo Nation , the self-governing territory of the Navajo people who refer to themselves as Diné .
geology
The uplift took place at the end of the Cretaceous Period and about 50 million years ago ( mya ), which was at the same time towards the end of the Laramic mountain formation from 80 to 40 mya , in which the Rocky Mountains also formed. The Defiance Uplift lifted and tilted the boulder in such a way that the Defiance Plateau rose steeply in the east and then fell flat to the west. Traces of a shear movement as a result of blade displacement show that the uplift is not completely straight .
The Chuska Mountains join in the east and the Carrizo Mountains in the north .
The uplift took place so slowly that, on the surface sloping from east to west, watercourses could dig themselves into the relatively soft sandstone of the block, which belongs to the rock layer of De Chelly Sandstone . Several of these watercourses, which collected in the Chinle Wash , named after the town of Chinle , dug canyons with almost vertical walls into the rock. These converging gorges are the Canyon de Chelly , which not only because of its scenic and geological features, but also for its history as a settlement and refuge for prehistoric Anasazi and the Navajo Indians living there today as Canyon de Chelly National Monument as a memorial of the type a National Monument .
In the Oligocene and Lower Miocene around 28 to 19 million years ago, magma rose in the monoclines created by the uplift , the East Defiance Monocline in the east and the West Defiance Monocline in the west and emerged as lava to the surface. Around 50 of the total of more than 80 diatrems of the Navajo Volcanic Field , which encompasses a larger region, are on the Defiance Uplift . Due to its unusual rock composition, the volcanic field allows a look into the earth's mantle shortly after the Lamaric mountain formation.
history
The region was populated in prehistoric times by all the characteristic archaeological cultures belonging to the Anasazi . From the early basketmakers , whose first appearance cannot be precisely dated, to the builders of the pueblos from around 700 and the collapse of the Anasazi cultures around the year 1300. They had no direct successors in the region, the Zuñi and other peoples of the pueblo -Culture still live further east on the Rio Grande . The Hopi originally lived there as well, before being displaced in the 19th century in their current reservation in Arizona, west of the Defiant area.
New residents moved from northern regions to the southwest and the Defiance region. When the first Spaniards arrived in the area in the 16th century, they met the early Navajo . At the beginning of the 18th century, Spaniards set up a Spanish mission in St. Michaels in the south of the plateau, further missions arose in Ganado in the southwest of the area and the Emmanuel Mission in the north. In 1804/05 and then again in 1864 the Canyon de Chelly became the last refuge and shelter against military campaigns, first the Spaniards, then the US Army against the Navajo. In 1868 the survivors of the expulsion known as the Long Walk were allowed to return to their home region. They have been residing in the Defiant Plateau since then.
In 1876, the merchant Lorenzo Hubbell founded his first trading post in Ganado, the Hubbell Trading Post , which is designated a National Historic Site because of its special historical significance . Ten years later he founded an offshoot in Chinle.
Individual evidence
- ↑ Unless otherwise stated, the description is based on: Charles Supplee, Douglas Anderson, Barbara Anderson: Canyon de Chelly . KC Publications, Las Vegas, 1990. ISBN 0-88714-042-4 . Chapter A, Land of Canyons , pages 4-9
- ↑ a b Defiance Plateau in the Geographic Names Information System of the United States Geological Survey
- ↑ SM Cather: The Laramide Defiance Uplift . In: New Mexico Geological Society: Geology of the Zuni Plateau , 2003, ISBN 1-58546-089-3 , page 6 f.