USGS Science⌕ Search

Geology topics

George H. Billingsley

Publications and source records attributed to George H. Billingsley.

At least 19 recordsLinked to original sources
USGS2019

Geologic field photograph map of the Grand Canyon region, 1967–2010

The Grand Canyon geologic field photograph collection contains 1,211 geotagged photographs collected during 43 years of geologic mapping from 1967 to 2010. The photographs document some key geologic features, structures, and rock unit relations that were used to compile nine geologic maps of the Grand Canyon region published at 1:100,000 scale, and many more maps published at 1:24,000 scale. Metadata for each photograph include description, date captured, coordinates, and a keyword system that places each photograph in one or more of the following categories: arches and windows, breccia pipes and collapse structures, faults and folds, igneous rocks, landslides and rockfalls, metamorphic rocks, sedimentary rocks, sinkholes, and springs and waterfalls. Original photograph slides are available at the Northern Arizona University Cline Library Special Collections and Archives. The Geologic Field Photograph Map of the Grand Canyon Region, 1967–2010, is an interactive online map application that shows clusters of photograph thumbnails and popup windows that scale as users pan, zoom, and click around the map. The photographs can be filtered by category, searched based on date range, description, and keywords, and (or) downloaded. All information populated within the map is served from a ScienceBase record of the Grand Canyon field photograph collection that can be accessed at https://doi.org/10.5066/F7WS8SHW .

Arizona↗
USGS2014

Geologic map of the eastern quarter of the Flagstaff 30’ x 60’ quadrangle, Coconino County, northern Arizona

The eastern quarter of the Flagstaff 30′ x 60′ quadrangle includes eight USGS 1:24,000-scale quadrangles in Coconino County, northern Arizona (fig. 1, map sheet): Anderson Canyon, Babbitt Wash, Canyon Diablo, Grand Falls, Grand Falls SE, Grand Falls SW, Grand Falls NE, and Meteor Crater. The map is bounded by lat 35° to 35°30′ N. and long 111° to 111°15′ W. and is on the southern part of the Colorado Plateaus geologic province (herein Colorado Plateau). Elevations range from 4,320 ft (1,317 m) at the Little Colorado River in the northwest corner of the map area to about 6,832 ft (2,082 m) at the southwest corner of the map. This geologic map provides an updated geologic framework for the eastern quarter of the Flagstaff 30′ x 60′ quadrangle and is adjacent to two other recent geologic maps, the Cameron and Winslow 30′ x 60′ quadrangles (Billingsley and others, 2007, 2013). This geologic map is the product of a cooperative effort between the U.S. Geological Survey (USGS) and the Navajo Nation. It provides geologic information for resource management officials of the U.S. Forest Service, the Arizona Game and Fish Department, and the Navajo Nation Reservation (herein the Navajo Nation). Funding for the map was provided by the USGS geologic mapping program, Reston, Virginia. Field work on the Navajo Nation was conducted under a permit from the Navajo Nation Minerals Department. Any persons wishing to conduct geologic investigations on the Navajo Nation must first apply for, and receive, a permit from the Navajo Nation Minerals Department, P.O. Box 1910, Window Rock, Arizona 86515, telephone (928) 871-6587.

Arizona↗
USGS2013

Geologic map of the Winslow 30’ × 60’ quadrangle, Coconino and Navajo Counties, northern Arizona

The Winslow 30’ × 60’ quadrangle encompasses approximately 5,018 km 2 (1,960 mi 2 ) within Coconino and Navajo Counties of northern Arizona. It is characterized by gently dipping Paleozoic and Mesozoic strata that dip 1° to 2° northeastward in the southwestern part of the quadrangle and become nearly flat-lying in the northeastern part of the quadrangle. In the northeastern part, a shallow Cenozoic erosional basin developed about 20 million years ago, which subsequently was filled with flat-lying Miocene and Pliocene lacustrine sediments of the Bidahochi Formation, as well as associated volcanic rocks of the Hopi Buttes Volcanic Field. The lacustrine sediments and volcanic rocks unconformably overlie Triassic, Jurassic, and Cretaceous strata. Beginning about early Pliocene time, the Little Colorado River and its tributaries began to remove large volumes of Paleozoic and Mesozoic bedrock from the map area. This erosional development has continued through Pleistocene and Holocene time. Fluvial sediments accumulated episodically throughout this erosional cycle, as indicated by isolated Pliocene(?) and Pleistocene Little Colorado River terrace-gravel deposits on Tucker Mesa and Toltec Divide west of Winslow and younger terrace-gravel deposits along the margins of the Little Colorado River Valley. These gravel deposits suggest that the ancestral Little Colorado River and its valley has eroded and migrated northeastward toward its present location and largely parallels the strike of the Chinle Formation. Today, the Little Colorado River meanders within a 5-km (3-mi) wide valley between Winslow and Leupp, where soft strata of the Chinle Formation is mostly covered by an unknown thickness of Holocene flood-plain deposits. In modern times, the Little Colorado River channel has changed its position as much as a 1.5 km (1 mi) during flood events, but for much of the year the channel is a dry river bed. Surficial alluvial and eolian deposits cover extensive parts of the bedrock outcrops over the entire Winslow quadrangle.

Arizona↗
USGS2013

Geologic map of the Glen Canyon Dam 30’ x 60’ quadrangle, Coconino County, northern Arizona

The Glen Canyon Dam 30’ x 60’ quadrangle is characterized by nearly flat lying to gently dipping Paleozoic and Mesozoic sedimentary strata that overlie tilted Proterozoic strata or metasedimentary and igneous rocks similar to those exposed at the bottom of Grand Canyon southwest of the quadrangle. Mississippian to Permian rocks are exposed in the walls of Marble Canyon; Permian strata and minor outcrops of Triassic strata form the surface bedrock of House Rock Valley and Marble Plateau, southwestern quarter of the quadrangle. The Paleozoic strata exposed in Marble Canyon and Grand Canyon south of the map are likely present in the subsurface of the entire quadrangle but with unknown facies and thickness changes. The Mesozoic sedimentary rocks exposed along the Vermilion and Echo Cliffs once covered the entire quadrangle, but Cenozoic erosion has removed most of these rocks from House Rock Valley and Marble Plateau areas. Mesozoic strata remain over much of the northern and eastern portions of the quadrangle where resistant Jurassic sandstone units form prominent cliffs, escarpments, mesas, buttes, and much of the surface bedrock of the Paria, Kaibito, and Rainbow Plateaus. Jurassic rocks in the northeastern part of quadrangle are cut by a sub-Cretaceous regional unconformity that bevels the Entrada Sandstone and Morrison Formation from Cummings Mesa southward to White Mesa near Kaibito. Quaternary deposits, mainly eolian, mantle much of the Paria, Kaibito, and Rainbow Plateaus in the northern and northeastern portion of the quadrangle. Alluvial deposits are widely distributed over parts of House Rock Valley and Marble Plateau in the southwest quarter of the quadrangle. The east-dipping strata of the Echo Cliffs Monocline forms a general north-south structural boundary through the central part of the quadrangle, separating Marble and Paria Plateaus west of the monocline from the Kaibito Plateau east of the monocline. The Echo Cliffs Monocline continues north of the quadrangle into southern Utah. The gentle north- and northeast-dipping Mesozoic strata on the Kaibito and Rainbow Plateaus are partly interrupted by northwest-trending, broad-based, ill-defined synclines and anticlines. These broad-based structures form mesas and buttes near anticlinal crests and deeply incised drainages in synclinal valleys. The 1,300-ft-thick (396-m-thick) Navajo Sandstone erodes into a maze of tributary slot canyons in the northeastern part of the quadrangle. Mesozoic strata in the extreme northeast corner of the quadrangle dip gently southwest due to the influence of the Monument Upwarp in southeastern Utah and by an intrusive uplift (laccolith) that forms Navajo Mountain, a prominent 10,388 ft (3,166 m) landmark just northeast of the quadrangle.

Arizona↗
USGS2012

Geologic map of the Tuba City 30' x 60' quadrangle, Coconino County, northern Arizona

The Tuba City 30’ x 60’ quadrangle encompasses approximately 5,018 km² (1,920 mi²) within Coconino County, northern Arizona. It is characterized by nearly flat lying to gently dipping sequences of Paleozoic and Mesozoic strata that overly tilted Precambrian strata or metasedimentary and igneous rocks that are exposed at the bottom of Grand Canyon. The Paleozoic rock sequences from Cambrian to Permian age are exposed in the walls of Grand Canyon, Marble Canyon, and Little Colorado River Gorge. Mesozoic sedimentary rocks are exposed in the eastern half of the quadrangle where resistant sandstone units form cliffs, escarpments, mesas, and local plateaus. A few Miocene volcanic dikes intrude Mesozoic rocks southwest, northwest, and northeast of Tuba City, and Pleistocene volcanic rocks representing the northernmost extent of the San Francisco Volcanic Field are present at the south-central edge of the quadrangle. Quaternary deposits mantle much of the Mesozoic rocks in the eastern half of the quadrangle and are sparsely scattered in the western half. Principal folds are the north-south-trending, east-dipping Echo Cliffs Monocline and the East Kaibab Monocline. The East Kaibab Monocline elevates the Kaibab, Walhalla, and Coconino Plateaus and parts of Grand Canyon. Grand Canyon erosion has exposed the Butte Fault beneath the east Kaibab Monocline, providing a window into the structural complexity of monoclines in this part of the Colorado Plateau. Rocks of Permian and Triassic age form the surface bedrock of Marble Plateau and House Rock Valley between the East Kaibab and Echo Cliffs Monoclines. The Echo Cliffs Monocline forms a structural boundary between the Marble Plateau to the west and the Kaibito and Moenkopi Plateaus to the east. Jurassic rocks of the Kaibito and Moenkopi Plateaus are largely mantled by extensive eolian sand deposits. A small part of the northeast-dipping Red Lake Monocline is present in the northeast corner of the quadrangle. A broad and gentle elongated anticline, the Limestone Ridge Anticline, forms the crest of Marble Plateau. Here, Paleozoic and Mesozoic strata generally dip less than 1° to 2° in all directions from a central high area along Limestone Ridge north of Bodaway Mesa and east of Cedar Ridge and The Gap. The Limestone Ridge Anticline plunges gently southeast toward the Painted Desert at the south edge of the quadrangle and northward toward Lees Ferry, Arizona, at the north-central edge of the quadrangle. The Tuba City Syncline is a very broad northwest-southeast-oriented-synclinal downwarp that parallels the Echo Cliffs Monocline north of Tuba City. The Preston Mesa Anticline is a small fold present on Kaibito Plateau north of Tuba City.

Arizona↗
USGS2010

Geologic Map of the House Rock Valley Area, Coconino County, Northern Arizona

This geologic map is a cooperative effort of the U.S. Geological Survey (USGS), the Bureau of Land Management, the National Park Service, and the U.S. Forest Service to provide a geologic database for resource management officials and visitor information services. This map was produced in response to information needs related to a proposed withdrawal of three segregated land areas near Grand Canyon National Park, Arizona, from new hard rock mining activity. House Rock Valley was designated as the east parcel of the segregated lands near the Grand Canyon. This map was needed to provide connectivity for the geologic framework of the Grand Canyon segregated land areas. This geologic map of the House Rock Valley area encompasses approximately 280 mi2 (85.4 km2) within Coconino County, northern Arizona, and is bounded by longitude 111 degrees 37'30' to 112 degrees 05' W. and latitude 36 degrees 30' to 36 degrees 50' N. The map area is in the eastern part of the Arizona Strip, which lies within the southern Colorado Plateaus geologic province (herein Colorado Plateau). The Arizona Strip is the part of Arizona lying north of the Colorado River. The map is bound on the east by the Colorado River in Marble Canyon within Grand Canyon National Park and Glen Canyon National Recreation Area, on the south and west by the Kaibab National Forest and Grand Canyon National Game Preserve, and on the north by the Vermilion Cliffs Natural Area, the Paria Canyon Vermilion Cliffs Wilderness Area, and the Vermilion Cliffs National Monument. House Rock State Buffalo Ranch also bounds the southern edge of the map area. The Bureau of Land Management Arizona Field Office in St. George, Utah, manages public lands of the Vermilion Cliffs Natural Area, Paria Canyon - Vermilion Cliffs Wilderness and Vermilion Cliffs National Monument. The North Kaibab Ranger District in Fredonia, Arizona, manages U.S. Forest Service land along the west edge of the map area and House Rock State Buffalo Ranch. Other lands include about 13 sections of Arizona State land, about ? of a section of private land along House Rock Wash, and about 1? sections of private land at Cliff Dwellers Lodge, Vermilion Cliffs Lodge, and Marble Canyon, Arizona. Landmark features within the map area include the Vermilion Cliffs, Paria Plateau, Marble Canyon, and House Rock Valley. Surface drainage in House Rock Valley is to the east toward the Colorado River in Marble Canyon. Large tributaries of Marble Canyon from north to south include Badger Canyon, Soap Creek, Rider Canyon, North Canyon, Bedrock Canyon, and South Canyon. Elevations range from about 2,875 ft (876 m) at the Colorado River in the southeast corner of the map to approximately 7,355 ft (2,224 m) on the east rim of Paria Plateau along the north-central edge of the map area. Three small settlements are in the map area along U.S. Highway 89A, Cliff Dwellers Lodge, Vermilion Cliffs Lodge, and Marble Canyon, Arizona. The community of Jacob Lake is about 9 mi (14.5 km) west of House Rock Valley on the Kaibab Plateau. Lees Ferry is 5 mi (8 km) north of Marble Canyon and marks the confluence of the Paria and Colorado Rivers and the beginning of Marble Canyon. U.S. Highway 89A provides access to the northern part of the map area. Dirt roads lead south into House Rock Valley from U.S. Highway 89A and are collectively maintained by the Bureau of Land Management, the U.S. National Forest Service, and the Grand Canyon Trust. House Rock Valley is one of the few remaining areas where uniform geologic mapping is needed for connectivity to the regional Grand Canyon geologic framework. This information is useful to Federal and State resource managers who direct environmental and land management programs that encompass such issues as range management, biological studies, flood control, water, and mineral-resource investigations. The geologic information will support future and ongoing geologic investigations and scientific studies

Scientific Investigations Map↗
USGS2008

Geologic map of the Fredonia 30' x 60' quadrangle, Mohave and Coconino counties, northern Arizona

This geologic map is the result of a cooperative effort of the U.S. Geological Survey, the National Park Service, the U.S. Forest Service, and the Bureau of Land Management (BLM) and the Kaibab-Paiute Tribe to provide a regional geologic database for resource management officials of all government and agencies, city municipalities, private enterprises, and individuals of this part of the Arizona Strip. The Arizona Strip is part of northwestern Arizona north of the Colorado River and bounded by the States of Nevada and Utah. Field work on the Kaibab-Paiute Indian Reservation was conducted from 2002 to 2005 with permission from the Kaibab-Paiute Tribal Government of that administration and permission was granted to publish a geologic map of 4 quadrangles online (Billingsley and others, 2004). The Kaibab-Paiute Tribal government of 2006 to 2008 requested that all geologic information within the Kaibab-Paiute Indian Reservation not be published as part of the Fredonia 30' x 60' quadrangle (this publication). For further information, contact the Kaibab-Paiute Tribal government at HC 65 Box 2, Fredonia, Arizona, 86022, telephone # (928) 643-7245. Visitors to the Kaibab-Paiute Indian Reservation are required to obtain a permit and permission for access from the Tribal Offices at the junction of State Highway 389 and the paved road leading to Pipe Spring National Monument. The Fredonia 30' x 60' quadrangle encompasses approximately 5,018 km2 (1,960 mi2) within Mohave and Coconino Counties, northern Arizona and is bounded by longitude 112 deg to 113 deg W., and latitude 36 deg 30' to 37 deg N. The map area lies within the southern Colorado Plateaus geologic province (herein Colorado Plateau). The map area is locally subdivided into seven physiographic parts: the Grand Canyon (Kanab Canyon and its tributaries), Kanab Plateau, Uinkaret Plateau, Kaibab Plateau, Paria Plateau, House Rock Valley, and Moccasin Mountains as defined by Billingsley and others, 1997, (fig. 1). Elevations range from 2,737 m (8,980 ft) just west of State Highway 67 on the Kaibab Plateau, southeast corner of the map area to about 927 m (3,040 ft) in Kanab Canyon, south-central edge of the map area.

Arizona↗
USGS2007

Geologic map of Wupatki National Monument and vicinity, Coconino County, Northern Arizona

Introduction The geologic map of Wupatki National Monument is a cooperative effort between the U.S. Geological Survey, the National Park Service, and the Navajo Nation to provide geologic information for resource management officials of the National Park Service, U.S. Forest Service, Navajo Indian Reservation (herein the Navajo Nation), and visitor information services at Wupatki National Monument, Arizona. Funding for the map was provided in part by the Water Rights Branch of the Water Resources Division of the National Park Service. Field work on the Navajo Nation was conducted under a permit from the Navajo Nation Minerals Department. Any persons wishing to conduct geologic investigations on the Navajo Nation must first apply for, and receive, a permit from the Navajo Nation Minerals Department, P.O. Box 1910, Window Rock, Arizona 86515, telephone (928)-871-6587. Wupatki National Monument lies within the USGS 1:24,000-scale Wupatki NE, Wupatki SE, Wupatki SW, Gray Mountain, East of SP Mountain, and Campbell Francis Wash quadrangles in northern Arizona. The map is bounded approximately by longitudes 111? 16' to 111? 32' 30' W. and latitudes 35? 30' to 35? 37' 40' N. The map area is in Coconino County on the southern part of the Colorado Plateaus geologic province (herein Colorado Plateau). The map area is locally subdivided into three physiographic parts, the Coconino Plateau, the Little Colorado River Valley, and the San Francisco Volcanic Field as defined by Billingsley and others (1997) [fig. 1]. Elevations range from 4,220 ft (1,286 m) at the Little Colorado River near the northeast corner of the map area to about 6,100 ft (1,859 m) at the southwest corner of the map area. The small community of Gray Mountain is about 16 mi (26 km) northwest of Wupatki National Monument Visitor Center, and Flagstaff, Arizona, the nearest metropolitan area, is about 24 mi (38 km) southwest of the Visitor Center (fig. 1). U.S. Highway 89 provides access to the west entrance of Wupatki National Monument. A paved Coconino County road provides a loop from Wupatki National Monument south to Sunset Crater National Monument and back to U.S. Highway 89 about 10 mi (16 km) north of Flagstaff, Arizona. Access to Coconino National Forest is via dirt roads maintained by the National Forest Service. Several unimproved dirt roads on Babbitt Ranch lands provide limited access to remote areas north of Wupatki National Monument. Travel is mostly restricted to paved roads within Wupatki National Monument, and a dirt road that crosses the Little Colorado River provides access to the Navajo Nation area east and northeast of the Little Colorado River. The Little Colorado River crossing is not bridged and can be impassable when the river is flowing. Four-wheel-drive vehicles are recommended but not necessary for travel in remote parts of the Navajo Nation. Extra food and water are highly recommended for travel in this sandy area. Land ownership north of Wupatki National Monument forms a checkerboard pattern between private and State land. Coconino National Forest manages lands south of Wupatki National Monument and the National Park Service manages Wupatki National Monument. The Leupp and Tolani Lake Chapters of the Navajo Nation manage the area northeast and east of the Little Colorado River (see land management boundaries on map). The geologic map of Wupatki National Monument provides updated geologic framework information for this part of the Colorado Plateau. The geologic information supports Federal, State, and private land managers when conducting geologic, biologic, and hydrologic investigations and will support future and ongoing geologic and associated scientific investigations of all disciplines within the Wupatki National Monument area.

Arizona↗
USGS2007

Geologic map of the Cameron 30' x 60' quadrangle, Coconino County, northern Arizona

This geologic map is the result of a cooperative effort of the U.S. Geological Survey and the National Park Service in collaboration with the Navajo Nation and the Hopi Tribe to provide regional geologic information for resource management officials of the National Park Service, U.S. Forest Service, Navajo Indian Reservation (herein the Navajo Nation), the Hopi Tribe, and for visitor information services at Grand Canyon National Park, Arizona as well as private enterprises that have lands within the area. The Cameron 30’ x 60’ quadrangle encompasses approximately 5,018 km 2 (1,960 mi 2 ) within Coconino County, northern Arizona and is bounded by longitude 111° to 112° W., and latitude 35°30’ to 36° N. The map area is within the southern Colorado Plateaus geologic province (herein Colorado Plateau). The map area is locally subdivided into six physiographic areas: the Grand Canyon (including the Little Colorado River Gorge), Coconino Plateau, Marble Plateau, Little Colorado River Valley, Moenkopi Plateau, and the San Francisco Volcanic Field as defined by Billingsley and others, 1997 (fig. 1). Elevations range from about 2,274 m (7,460 ft) at the south rim of Grand Canyon along State Highway 64 to about 994 m (3,260 ft) in the Grand Canyon, northeast quarter of the map area. The Cameron quadrangle is one of the few remaining areas near the Grand Canyon where uniform geologic mapping was needed for geologic connectivity of the regional geologic framework that will be useful to federal, state, and private land resource managers who direct environmental and land management programs such as range management, biological studies, flood control, and water resource investigations. The geologic information presented will support future and ongoing local geologic investigations and associated scientific studies of all disciplines within the Cameron quadrangle area.

Arizona↗
USGS2006

Geologic map of the Valle 30' x 60' quadrangle, Coconino County, northern Arizona

The geologic map of the Valle 30' x 60' quadrangle is the result of a cooperative effort between the U.S. Geological Survey and the National Park Service to provide geologic information for regional resource management and visitor information services for Grand Canyon National Park, Arizona. The map area encompasses approximately 1,960 sq.mi. within Coconino County, northern Arizona and is bounded by long 112 deg to 113 deg W. and lat 35 deg 30 min to 36 deg N. and lies within the southern Colorado Plateaus geologic province (herein Colorado Plateau). The map area is locally subdivided into four physiographic parts; (1) the Grand Canyon (Cataract Canyon and extreme northeast corner of the map area), (2) the Coconino Plateau, (3) the Mount Floyd Volcanic Field, and (4) the San Francisco Volcanic Field as defined by Billingsley and others, 1997. Elevations range from 7,460 ft (2,274 m) on the Coconino Plateau along State Highway 64 northeast corner of the map area, to about 4,200 ft (1,280 m) at the bottom of Cataract Canyon. Settlements within the map area include Tusayan and Valle, Arizona. State Highway 64 and U.S. Highway 180 provide access to the Tusayan and Valle areas. Indian Route 18 is a paved highway in the northwest corner of the map area that is maintained by the Hualapai and Havasupai Indian Tribes and leads from State Route 66 about 7 mi (11 km) east of Peach Springs, Arizona to Hualapai Hilltop, a parking lot just north of the map area at the rim of Cataract Canyon where visitors begin an 8 mi (13 km) hike into Havasupai, Arizona. Other remote parts of the map are accessed by two dirt roads, which are maintained by Coconino County, and by several unmaintained local ranch roads. Weather conditions restrict travel within the area and visitors must obtain permission to access a few local ranch lands in the south-central edge of the map area. Extra water and food are highly recommended when traveling in this remote region. Access into Cataract Canyon is restricted to horse or foot travel and visitors must obtain permission from the Havasupai Tribe to hike within the Havasupai Indian Reservation. In the central part of the map area, most of the land is privately owned and managed by the Babbitt Ranches Inc. in conjunction with the Nature Conservancy and the Navajo Tribe. In the southern half of the map, land alternates between privately owned land and State land forming a checkerboard pattern. The National Park Service manages land in Grand Canyon National Park (extreme northeast edge of map area), the U.S. Forest Service manages lands in the Kaibab National Forest, the Hualapai Tribe manages lands in the northwest quarter of the map area, and the Havasupai Tribe manages lands within Cataract Canyon and adjacent parts of the Coconino Plateau.

Scientific Investigations Map↗
USGS2006

Geologic map of the Peach Springs 30' x 60' quadrangle, Mohave and Coconino counties, northwestern Arizona

This map is a product of a cooperative project of the U.S. Geological Survey, the U.S. National Park Service, and the Bureau of Land Management to provide geologic map coverage and regional geologic information for visitor services and resource management of Grand Canyon National Park, Lake Mead National Recreation Area, Grand Canyon-Parashant-National Monument, and adjacent lands in northwestern Arizona. This map is a synthesis of previous and new geologic mapping that encompasses the Peach Springs 30' x 60' quadrangle, Arizona. The geologic data will support future geologic, biologic, hydrologic, and other science resource studies of this area conducted by the National Park Service, the Hualapai Indian Tribe, the Bureau of Land Management, the State of Arizona, and private organizations. The Colorado River and its tributaries have dissected the southwestern Colorado Plateau into what is now the southwestern part of Grand Canyon. The erosion of Grand Canyon has exposed about 426 m (1,400 ft) of Proterozoic crystalline metamorphic rocks and granite, about 1,450 m (4,760 ft) of Paleozoic strata, and about 300 m (1,000 ft) of Tertiary sedimentary rocks. Outcrops of Proterozoic crystalline rocks are exposed at the bottom of Grand Canyon at Granite Park from Colorado River Mile 207 to 209, at Mile 212, and in the Lower Granite Gorge from Colorado River Mile 216 to 262, and along the Grand Wash Cliffs in the southwest corner of the map area.

Arizona↗
USGS2004

Geologic map of the Lower Grand Wash cliffs and vicinity, Mohave County, Northwestern Arizona

This digital map database is compiled from unpublished data and new mapping by the authors and represents the general distribution of surficial and bedrock geology in the mapped area. Together with the accompanying pamphlet, it provides current information on the geologic structure and stratigraphy of the area. The database dilineates map units that are identified by age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The scale of the source maps limits the spatial resolution of the database to 1:31,680 or smaller.

Miscellaneous Field Studies Map↗
USGS2004

Geologic Map of Pipe Spring National Monument and the Western Kaibab-Paiute Indian Reservation, Mohave County, Arizona

The digital map publication, compiled from previously published and unpublished data and new mapping by the author, represents the general distribution of surficial and bedrock geology in Pipe Spring National Monument and vicinity, including the following 1:24,000-scale U.S. Geological Survey (USGS) quadrangles: Moccasin, Kaibab, Pipe Valley, and Pipe Spring. Together with the accompanying geologic description pamphlet, it presents current knowledge of the geologic structure and stratigraphy of the area covered. The database identifies map units that are classified by age and lithology following the stratigraphic nomenclature of the USGS. The scale of the source maps limits the spatial resolution (scale) of the database to 1:24,000 or smaller. Note: The extent of this database conforms to the boundaries of the four quadrangles listed above; however, the topographic base maps produced by the USGS for the Moccasin and Kaibab quadrangles extend slightly to the north of the 37-degree latitude line that should define the northern limit of these 7.5- minute quadrangles. Thus, if this database is overlain with a digital file of quadrangle boundaries there is a mismatch.

Scientific Investigations Map↗
USGS2003

Geologic map of the Mount Trumbull 30' X 60' quadrangle, Mohave and Coconino Counties, northwestern Arizona

The geologic map of the Mount Trumbull 30' x 60' quadrangle is a cooperative product of the U.S. Geological Survey, the National Park Service, and the Bureau of Land Management that provides geologic map coverage and regional geologic information for visitor services and resource management of Grand Canyon National Park, Lake Mead Recreational Area, and Grand Canyon Parashant National Monument, Arizona. This map is a compilation of previous and new geologic mapping that encompasses the Mount Trumbull 30' x 60' quadrangle of Arizona. This digital database, a compilation of previous and new geologic mapping, contains geologic data used to produce the 100,000-scale Geologic Map of the Mount Trumbull 30' x 60' Quadrangle, Mohave and Coconino Counties, Northwestern Arizona. The geologic features that were mapped as part of this project include: geologic contacts and faults, bedrock and surficial geologic units, structural data, fold axes, karst features, mines, and volcanic features. This map was produced using 1:24,000-scale 1976 infrared aerial photographs followed by extensive field checking. Volcanic rocks were mapped as separate units when identified on aerial photographs as mappable and distinctly separate units associated with one or more pyroclastic cones and flows. Many of the Quaternary alluvial deposits that have similar lithology but different geomorphic characteristics were mapped almost entirely by photogeologic methods. Stratigraphic position and amount of erosional degradation were used to determine relative ages of alluvial deposits having similar lithologies. Each map unit and structure was investigated in detail in the field to ensure accuracy of description. Punch-registered mylar sheets were scanned at the Flagstaff Field Center using an Optronics 5040 raster scanner at a resolution of 50 microns (508 dpi). The scans were output in .rle format, converted to .rlc, and then converted to ARC/INFO grids. A tic file was created in geographic coordinates and projected into the base map projection (Polyconic) using a central meridian of -113.500. The tic file was used to transform the grid into Universal Transverse Mercator projection. The linework was vectorized using gridline. Scanned lines were edited interactively in ArcEdit. Polygons were attributed in ArcEdit and all artifacts and scanning errors visible at 1:100,000 were removed. Point data were digitized onscreen. Due to the discovery of digital and geologic errors on the original files, the ARC/INFO coverages were converted to a personal geodatabase and corrected in ArcMap. The feature classes which define the geologic units, lines and polygons, are topologically related and maintained in the geodatabase by a set of validation rules. The internal database structure and feature attributes were then modified to match other geologic map databases being created for the Grand Canyon region. Faults were edited with the downthrown block, if known, on the 'right side' of the line. The 'right' and 'left' sides of a line are determined from 'starting' at the line's 'from node' and moving to the line's end or 'to node'.

Arizona↗
USGS2003

Geologic map of upper Clayhole Valley and vicinity, Mohave County, northwestern Arizona

This digital map database is compiled from unpublished data and new mapping by the authors and represents the general distribution of surficial and bedrock geology in the mapped area. Together with the accompanying pamphlet, it provides current information on the geologic structure and stratigraphy of the area. The database delineates map units that are identified by age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The scale of the source maps limits the spatial resolution of the database to 1:31,680 or smaller.

Miscellaneous Field Studies Map↗
USGS2002

Surficial Geologic Map of The Loop and Druid Arch Quadrangles, Canyonlands National Park, Utah

This geologic map is a product of a cooperative project between the U.S. Geological Survey and the U.S. National Park Service to provide geologic information about this part of Canyonlands National Park, Utah. This digital map database contains bedrock data from previously published data that has been modified by the author. New mapping of the surficial deposits represents the general distribution of surficial deposits of the Druid Arch and The Loop 7.5-minute quadrangles.

Miscellaneous Field Studies Map↗
USGS2001

Geologic Map of the Cane Quadrangle, Coconino County, Northern Arizona

This digital map database is compiled from unpublished data and new mapping by the authors, represents the general distribution of surficial and bedrock geology in the mapped area. Together with the accompanying pamphlet, it provides current information on the geologic structure and stratigraphy of the area. The database delineate map units that are identified by age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The scale of the source maps limits the spatial resolution of the database to 1:24,000 or smaller.

Miscellaneous Field Studies Map↗
USGS2001

Geologic Map of Part of the Uinkaret Volcanic Field, Mohave County, Northwestern Arizona

The geologic map of part of the Uinkaret Volcanic Field is one product of a cooperative project between the U.S. Geological Survey, the National Park Service, and the Bureau of Land Management to provide geologic information about this part of the Grand Canyon-Parashant Canyon National Monument of Arizona. The Uinkaret Volcanic Field is a unique part of western Grand Canyon where volcanic rocks have preserved the geomorphic development of the landscape. Most of the Grand Canyon, and parts of adjacent plateaus have already been mapped. This map completes one of the remaining areas where uniform quality geologic mapping was needed. A few dozen volcanoes and lava flows within the Grand Canyon are not included in the map area, but their geologic significance to Grand Canyon development is documented by Hamblin (1994) and mapped by Billingsley and Huntoon (1983) and Wenrich and others (1997). The geologic information in this report may be useful to resource managers of the Bureau of Land Management for range management, biological, archaeological, and flood control programs. The map area lies within the Shivwits, Uinkaret, and Kanab Plateaus, which are subplateaus of the Colorado Plateaus physiographic province (Billingsley and others, 1997), and is part of the Arizona Strip north of the Colorado River. The nearest settlement is Colorado City, Arizona, about 58 km (36 mi) north of the map area (fig. 1). Elevations range from about 2,447 m (8,029 ft) at Mount Trumbull, in the northwest quarter of the map area, to about 732 m (2,400 ft) in Cove Canyon, in the southeast quarter of the map area. Vehicle access is via the Toroweap and Mount Trumbull dirt roads (fig. 1). Unimproved dirt roads traverse other parts of the area except in designated wilderness. Extra fuel, two spare tires, and extra food and water are highly recommended for travelers in this remote area. The U.S. Bureau of Land Management, Arizona Strip Field Office, St. George, Utah manages most of the area. In addition, there are 12 sections belonging to the State of Arizona, about 12 sections are private land, and several sections are within the Grand Canyon National Park and Lake Mead National Recreational Area (U.S. Department of the Interior, 1993). The private land is in Potato Valley and Lake Valley, southwest and west of Mount Trumbull, and in Whitmore Canyon and Toroweap (Tuweap) Valley. Portions of the Sawmill Mountains, Mount Logan, and Mount Trumbull areas were originally established as part of the Dixie National Forest in 1904. In 1924, Dixie National Forest land became part of the Kaibab National Forest. Then on February 13, 1974, management of this part of the Kaibab National Forest was transferred to the Bureau of Land Management, Arizona Strip Field Office (personal commun. Becky Hammond, Bureau of Land Management, 1997). Mount Logan and part of the Sawmill Mountains are now designated as the Mount Logan Wilderness Area, and Mount Trumbull is designated as the Mount Trumbull Wilderness Area. Most of the map area is now part of the new Grand Canyon-Parashant Canyon National Monument established January 11, 2000. Lower elevations within Hells Hollow, Whitmore Canyon, Toroweap Valley, and Cove Canyon support a sparse growth of sagebrush, cactus, grass, and a variety of desert shrubs. Sagebrush, grass, cactus, cliffrose bush, pinion pine, and juniper trees thrive at elevations above 1,830 m (6,000 ft). Ponderosa pine and oak forests thrive at higher elevations in the Mount Trumbull and Mount Logan areas. Surface runoff within the map area drains south towards the Colorado River through Hells Hole, Hollow, Whitmore Canyon, Toroweap Valley, and Cove Canyon. Upper Toroweap Valley, upper Hells Hollow, and Whitmore Canyon are part of the physiographic area of Grand Canyon, but are not within Grand Canyon National Park (Billingsley and others, 1997). As of January 11, 2000, these areas are now part of the new Grand Canyon-Parashant

Miscellaneous Field Studies Map↗