The Defiance Plateau, part of the geologic Defiance Uplift, is an approximately 75-mile (121 km) long, mostly north-trending plateau of
Apache County,
Arizona
Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...
, with its east and southeast perimeter, as parts of
San Juan and
McKinley Counties,
New Mexico
)
, population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano)
, seat = Santa Fe
, LargestCity = Albuquerque
, LargestMetro = Tiguex
, OfficialLang = None
, Languages = English, Spanish ( New Mexican), Navajo, Ke ...
.
The west and southwest of the plateau region borders the east, southeast of the
Painted Desert, where the
Puerco River
The Puerco River or Rio Puerco is a tributary of the Little Colorado River in northwestern New Mexico and northeastern Arizona. It flows through arid terrain, including the Painted Desert.
Name
The Puerco River is sometimes called Rio Puerco ...
enters the desert, flowing southwest from New Mexico then meeting the
Little Colorado River which flows northwest through the Painted Desert – (light tan & arc-shaped), to the
Colorado River
The Colorado River ( es, Río Colorado) is one of the principal rivers (along with the Rio Grande) in the Southwestern United States and northern Mexico. The river drains an expansive, arid watershed that encompasses parts of seven U.S. s ...
(at the northeast of the
Grand Canyon). The Puerco River is the plateau's border on the south and southeast; at the northwest, the
Black Mesa is the northwest border, and the north of the Defiance Plateau is bounded by the south of the
Chinle Valley, where
Chinle Creek flows north to meet the
San Juan River in southeast
Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...
.
![Littlecoloradomap](https://upload.wikimedia.org/wikipedia/commons/9/9e/Littlecoloradomap.png)
The north terminus region of the Defiance Plateau contains three canyons, with watercourses flowing due-west, as headwaters of Chinle Creek. The canyons are the
Canyon de Chelly National Monument
Canyon de Chelly National Monument ( ) was established on April 1, 1931, as a unit of the National Park Service. Located in northeastern Arizona, it is within the boundaries of the Navajo Nation and lies in the Four Corners region. Reflecting on ...
; two other canyons are southwest, part of the five canyon system, Little White House and Three Turkey Canyons.
The Defiance Plateau is part of the
Navajo Nation
The Navajo Nation ( nv, Naabeehó Bináhásdzo), also known as Navajoland, is a Native American reservation in the United States. It occupies portions of northeastern Arizona, northwestern New Mexico, and southeastern Utah; at roughly , the ...
. At the plateau's southeast, on
Black Creek lies the site of
Window Rock, Arizona
Window Rock ( nv, , ) is a census-designated place that serves as the seat of government and capital of the Navajo Nation, the largest territory in North America of a sovereign Native American nation. The capital lies within the boundaries of the ...
, the Navajo Nation capitol.
The highpoint of the plateau is Fluted Rock, southwest of
Sawmill, Arizona
Sawmill ( nv, ) is a census-designated place (CDP) in Apache County, Arizona, United States. Sawmill is a part of Fort Defiance Agency, which is on the Navajo Nation. The population was 748 at the 2010 census. It is named after and developed a ...
, .
Description
![Map of the Navajo Volcanic Fields](https://upload.wikimedia.org/wikipedia/commons/3/3d/Map_of_the_Navajo_Volcanic_Fields.jpg)
The Defiance Plateau is the central area of an uplifted region. To the north/northeast are the
Lukachukai Mountains, part of the Defiance Plateau border; they form a southeast section of
Chinle Valley's border. South of the Lukachukais is the rest of the east border of the Defiance Plateau, the
Chuska Mountains
''
The Chuska Mountains are an elongate range on the southwest Colorado Plateau and within the Navajo Nation whose highest elevations approach 10,000 feet. The range is about 80 by 15 km (50 by 10 miles). It trends north-northwest and is cross ...
; the Chuskas trend northwest in the north; at the plateaus east, the Chuskas trend more southerly, and attached at the south is Manuelito Plateau, in New Mexico, the east border of the south-flowing
Black Creek at the southeast perimeter region of the Defiance Plateau.
South and southwest
The south perimeter of the Defiance Plateau is bordered by the
Puerco River
The Puerco River or Rio Puerco is a tributary of the Little Colorado River in northwestern New Mexico and northeastern Arizona. It flows through arid terrain, including the Painted Desert.
Name
The Puerco River is sometimes called Rio Puerco ...
, flowing southwest from the Continental Divide in northwest New Mexico. The Puerco intersects the
Little Colorado River at the southeast edge of the Painted Desert, where the Little Colorado runs directly northwest (then due-north, and then back to northwest) to eventually meet the Colorado River. Numerous mesas trend from the northeast (west and southwest sides of the
Black Mesa) as drainage basin perimeters feeding the Little Colorado. At the southwest of the Defiance Plateau, is Padre Mesa; north is Ganada Mesa, (
Ganado, Arizona
Ganado ( nv, ) is a chapter of the Navajo Nation and census-designated place (CDP) in Apache County, Arizona, United States. The population was 1,210 at the 2010 census.
Ganado is part of the Fort Defiance Agency, of the Bureau of Indian A ...
), and northeast of Grand Mesa is Oak Creek Mountain, where the plateau highpoint is located, Fluted Rock, 4-mi southwest of
Sawmill, Arizona
Sawmill ( nv, ) is a census-designated place (CDP) in Apache County, Arizona, United States. Sawmill is a part of Fort Defiance Agency, which is on the Navajo Nation. The population was 748 at the 2010 census. It is named after and developed a ...
.
North and northwest
The northwest of the Defiance Plateau merges into the southeast of the
Black Mesa, (southeast-trending, the same trendline as the Painted Desert). Black Mesa is also the west border of
Chinle Valley, where the south-center, and southeast of the valley becomes part of the north perimeter of the plateau. Northeast and east are the mountain ranges that trend southward, and become the eastern parts of the Defiance Plateau. The
Carrizo Mountains stand alone northeast; the
Lukachukai Mountains are connected to the north Chuskas, and the extensive
Chuska Mountains
''
The Chuska Mountains are an elongate range on the southwest Colorado Plateau and within the Navajo Nation whose highest elevations approach 10,000 feet. The range is about 80 by 15 km (50 by 10 miles). It trends north-northwest and is cross ...
are attached to the Defiance Plateau at the east, with headwaters flowing west, or northwest into Canyon de Chelly or southeast Chinle Valley. In the south Chuskas, the Black Creek, and
Red Lake, at the Red Valley region, southeast of Sawmill, form the final southeast perimeter region of the Defiance Plateau.
Plateau center region
The center region is near Sawmill, Arizona.
Beautiful Valley to the northwest contains Nazlini Wash, where the wash is a southwest-tributary to the due-north flowing Chinle Creek system. The watershed origins also come from the southwest near Ganado, closer to the southwest Defiance Plateau perimeter. At Sawmill, northeast of Ganado is Bonito Canyon a northwest tributary to south-flowing Black Creek. The
water divide separating the Chinle Creek watershed, (southeast, with Canyon de Chelly), is 3-mi north-northeast of Sawmill.
Geology
The Defiance Plateau is the topographic expression of the Defiance Uplift, a block of the
Earth's crust that has been repeatedly elevated through geologic time. The uplift is asymmetric, dipping steeply into the Defiance monocline on its eastern boundary but gently (with dip angles typically less than three degrees) to the west. The uplift is relatively unfaulted, except for local faulting at Tsaile graben in the northwestern part of the uplift and the Wide Ruins fault zone across the southern part of the uplift. The uplift is separated from the
Zuni uplift by the Gallup sag.
The central part of the uplift exposes
Permian
The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last ...
beds (
Supai Group and
Coconino Sandstone
Coconino Sandstone is a geologic formation named after its exposure in Coconino County, Arizona. This formation spreads across the Colorado Plateau province of the United States, including northern Arizona, northwest Colorado, Nevada, and Utah.
...
) while the outer portions of the uplift, particularly to the north, expose
Triassic
The Triassic ( ) is a geologic period and system (stratigraphy), system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago (Year#Abbreviations yr and ya, Mya), to the beginning of the Jurassic Period 201.36 ...
Chinle Formation. Strata as young as the
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...
Mesaverde Group
The Mesaverde Group is a Late Cretaceous stratigraphic group found in areas of Colorado, New Mexico, Utah, and Wyoming, in the Western United States.
History
The Mesaverde Formation was first described by W.H.Holmes in 1877 during the Hayden ...
are found around the flanks of the uplift, particularly on the Defiance monocline. The Permian beds rest
unconformably
An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval ...
on
Proterozoic gneiss
Gneiss ( ) is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. Gneiss forms at higher temperatures a ...
and
granite
Granite () is a coarse-grained ( phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies under ...
, showing that the uplift existed in the
Pennsylvanian and was stripped of sedimentary cover by erosion. The uplift was subsequently buried by sediments during the
Mesozoic
The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretace ...
but was again uplifted and partially stripped in the late
Jurassic
The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...
or early Cretaceous, possibly contributing significant sediments to the
Morrison Morrison may refer to:
People
* Morrison (surname), people with the Scottish surname Morrison
* Morrison Heady (1829–1915), American poet
* Morrison Mann MacBride (1877–1938), Canadian merchant
Places in the United States
* Morrison, Colorad ...
,
Dakota
Dakota may refer to:
* Dakota people, a sub-tribe of the Sioux
** Dakota language, their language
Dakota may also refer to:
Places United States
* Dakota, Georgia, an unincorporated community
* Dakota, Illinois, a town
* Dakota, Minnesota, ...
, or
Cedar Mountain Formation
The Cedar Mountain Formation is the name given to a distinctive sedimentary geologic formation in eastern Utah, spanning most of the early and mid- Cretaceous. The formation was named for Cedar Mountain in northern Emery County, Utah, where Will ...
s.
Access to the region
US 191
U.S. Route 191 (US 191) is a spur of U.S. Route 91 that has two branches. The southern branch runs for from Douglas, Arizona on the Mexican border to the southern part of Yellowstone National Park. The northern branch runs for from the nort ...
traverses mesas on the west perimeter of the Defiance Plateau, from
Interstate 40
Interstate 40 (I-40) is a major east–west Interstate Highway running through the south-central portion of the United States. At a length of , it is the third-longest Interstate Highway in the country, after I-90 and I-80. From west to ea ...
on the south and southeast plateau perimeter, following the course of the
Puerco River
The Puerco River or Rio Puerco is a tributary of the Little Colorado River in northwestern New Mexico and northeastern Arizona. It flows through arid terrain, including the Painted Desert.
Name
The Puerco River is sometimes called Rio Puerco ...
from New Mexico. At the plateaus southeast, IR-12-(BIA-12) traverses north from I-40 to follow the
Black Creek rivercourse, in Arizona. At the north, IR-12 meets
Red Lake (Arizona - New Mexico) and
Navajo, NM in Red Valley; IR-12 then traverses northeast, intersecting with
New Mexico Road 134 through the
Chuska Mountains
''
The Chuska Mountains are an elongate range on the southwest Colorado Plateau and within the Navajo Nation whose highest elevations approach 10,000 feet. The range is about 80 by 15 km (50 by 10 miles). It trends north-northwest and is cross ...
, turning east to meet
U.S. 491.
IR-12, exits from NM 134 going north then northeast following the west flank of the Chuskas to meet US 191 north of Canyon de Chelly in the Chinle Valley-(at Lukachukai Creek, eventually reaching
Round Rock, Arizona).
The center-south of the Defiance Plateau is traversed east-west by
Arizona State Route 264
State Route 264 (SR 264) is a state highway in northeastern Arizona, that runs from a junction with US 160 near Tuba City to the New Mexico state line at Window Rock, where the highway continues as New Mexico State Road 264 (NM 264).
Ro ...
. Window Rock is at the southeast, on Black Creek, (southern Chuskas, Manuelito Plateau);
Ganado, Arizona
Ganado ( nv, ) is a chapter of the Navajo Nation and census-designated place (CDP) in Apache County, Arizona, United States. The population was 1,210 at the 2010 census.
Ganado is part of the Fort Defiance Agency, of the Bureau of Indian A ...
is in the center-southwest plateau region, where the mesas trend northwesterly along the northeast perimeter of the Painted Desert. The west terminus of AZ 264 is
Tuba City, Arizona
Tuba City ( nv, ) is an unincorporated town in Coconino County, Arizona, on the Navajo Nation, United States. It is the second-largest community in Coconino County. The population of the census-designated place (CDP) was 8,611 at the 2010 cen ...
adjacent
U.S. 89.
File:Window rock AZ.jpg, Window Rock (landform)
at Window Rock, Arizona
Window Rock ( nv, , ) is a census-designated place that serves as the seat of government and capital of the Navajo Nation, the largest territory in North America of a sovereign Native American nation. The capital lies within the boundaries of the ...
File:CACHmap1 relief.png, Canyon de Chelly National Monument
Canyon de Chelly National Monument ( ) was established on April 1, 1931, as a unit of the National Park Service. Located in northeastern Arizona, it is within the boundaries of the Navajo Nation and lies in the Four Corners region. Reflecting on ...
canyons, and the additional 2 canyons at southwest
See also
*
Bidahochi Formation
Footnotes
References
*
*
*
Further reading
* New Mexico DeLorme Atlas & Gazetteer, 5th Edition, c. 2009, 72 pages, pp. 12, 20.
External links
Fluted Rock, (southwest of Sawvill), near Defiance Plateau center, (lat-long.com), (coordinates, 8294 ft)
{{Authority control
Colorado Plateau
Geography of the Navajo Nation
Landforms of Apache County, Arizona
Landforms of McKinley County, New Mexico
Landforms of San Juan County, New Mexico
Geology of Arizona
Geology of New Mexico
Plateaus of Arizona
Landforms of New Mexico