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Base from U.S. Geological Survey, Cameron, 1983 

Universal Transverse Mercator Projection

Any use of trade, product, or firm names in this publication is for descriptive 

purposes only and does not imply endorsement by the U.S. Government.

For sale by U.S. Geological Survey, Information Services, Box 25286, 

Federal Center, CO 80225, 1–888–ASK–USGS

Digital files available at http://pubs.usgs.gov/sim/2007/2977

Printed on recycled paper

Geology mapped in 2003–2006 by G.H. Billingsley

Digital database by S.S. Priest and T.J. Felger 

Edited by T. Iki; cartography by D.A. Ryan

Manuscript approved for publication June 22, 2007

ARIZONA

MAP LOCATION

35°45'

35 ̊30'

111°15' 111°00'

35°45'

Prepared in cooperation with the

National Park Service, the Navajo Nation, and the Hopi Tribe

Scientific Investigations Map 2977

Pamphlet accompanies map

112°00'

36°00'

111°00'

36°00'

35°37'30"

35°52'30"

35°37'30"

35°52'30"

U.S. Department of the Interior

U.S. Geological Survey

R4E

T30N

1 012 4 3 56789 10 KILOMETERS

SCALE 1:100 000

1 0 2 1 3 4 5 6 7 8 MILES

CONTOUR INTERVAL 50 METERS

Geologic Map of the Cameron 30' x 60' Quadrangle, Coconino County, Northern Arizona

By

George H. Billingsley, Susan S. Priest, and Tracey J. Felger

2007

ARIZONA

MAP LOCATION

R121⁄2E

T25N

35°30'

R4E 111°52'30" R5E R6E 111°37'30" 112°00' 111°45' R7E 111°07'30" R8E 111°30' R9E R1W 111°22'30" R10E R11E R12E

T26N

T27N

T28N

T29N

T30N

111°22'30" R10E 111°15' R11E 111°07'30" R12E R121⁄2E 111°52'30" R5E 111°45'00" R6E R7E 111°37'30" R8E 111°30' R9E

T29N

T28N

T27N

T26N

T25N

QUATERNARY

TERTIARY

TERTIARY

JURASSIC

TRIASSIC

Lower Permian PERMIAN

SEDIMENTARY ROCKS

CRETACEOUS

UNITS SHOWN ONLY

IN CROSS SECTION

Pliocene

Middle(?) and

Lower Triassic

Lower Jurassic

and Upper Triassic(?)

Holocene

Pleistocene

Pleistocene QUATERNARY

Pliocene and Miocene(?)

Middle Jurassic

Upper Cretaceous

Lower Triassic

Lower Jurassic

Upper Triassic

Pliocene

Great Unconformity

Upper and Lower

Mississippian

Middle Cambrian

Paleoproterozoic

Upper, Middle and Lower

Pennsylvanian and Upper

Mississippian

Upper and Middle

Devonian

Middle and

Lower(?) Cambrian

Miocene

TERTIARY

PENNSYLVANIAN

DEVONIAN

CAMBRIAN

PROTEROZOIC

MISSISSIPPIAN

CAMBRIAN

Miocene

Glen Canyon Group

Supai Group

Tonto Group

CORRELATION OF MAP UNITS

SURFICIAL DEPOSITS

VOLCANIC ROCKS

Volcanic Rocks of the San Francisco Volcanic Field

Unconformity

Unconformity

Unconformity

Unconformity

Unconformity

Unconformity

Unconformity

Unconformity

Unconformity

Unconformity

Unconformity

Unconformity

Unconformity

Unconformity

COCONINO

PLATEAU

BLACK POINTMONOCLINE

Black Point Little Colorado River Valley Little Colorado River

WARD TERRACE Red Rock Cliffs

ADEII EECHII CLIFFS

MOENKOPI PLATEAU

Appaloosa Ridge COAL MINE MESA

METERS

A'

SEA LEVEL

2000

1800

1600

1400

1200

1000

800

600

400

200

METERS

A

SEA LEVEL

2000

1800

1600

1400

1200

1000

800

600

400

200

100 meters = 328 feet

All structural trends and patterns are schematic

Xu, _t, and _ba shown only in cross section

VERTICAL EXAGGERATION X2

VERTICAL EXAGGERATION X2

COCONINO PLATEAU Gray Mountain COCNINO POINT

MONOCLINE

BLUE SPRING

MONOCLINE

MARBLE PLATEAU

Little Colorado River

Moenkopi Wash

METERS

B'

SEA LEVEL

2000

1800

2400

2200

1600

1400

1200

1000

800

600

400

200

100 meters = 328 feet

All structural trends and patterns are schematic

Xu, _t, and _ba shown only in cross section

METERS

B

SEA LEVEL

2400

1800

1600

2200

2000

1400

1200

1000

800

600

400

200

METERS

C'

SEA LEVEL

2000

1800

2400

2200

1600

1400

1200

1000

800

600

400

200

100 meters = 328 feet VERTICAL EXAGGERATION X2

All structural trends and patterns are schematic

Xu, _t, and _ba shown only in cross section

METERS

C

SEA LEVEL

2400

1800

1600

2200

2000

1400

1200

1000

800

600

400

200

GRANDVIEW

MONOCLINE COCONINO PLATEAU

EAST KAIBAB

MONOCLINE

MARBLE PLATEAU

Little Colorado River Gorge

111°00' 112°00'

36°00'

35°30'

0 5 10 15 20 KILOMETERS

0 5 10 15 20 MILES

Cameron 1:100,000-scale geology and major structures draped over hillshade derived from 30-meter digital 

elevation model.

Mesa Butte Fault

Skinner Ridge

Anticline

Red Horse Syncline

Red Horse Anticline

East Kaibab

Monocline

Mesa Butte Graben

Echo Cliffs

Monocline

Grandview Monocline

Coconino Point Monocline

Burro Canyon Graben

Blue Spring

Monocline

Coconino Point Monocline

Black Point Monocline

Doney

Mountain Fault

Cedar Ranch

Fault

LIST OF MAP UNITS

[Some unit exposures on the printed map are too small to distinguish the color for unit identification. These 

units are labeled where possible, and unlabeled units are attributed in the geodatabase.]

SURFICIAL DEPOSITS

Artificial fill and quarries (Holocene)

Stream-channel deposits (Holocene)

Flood-plain deposits (Holocene)

Dune sand and sand sheet deposits (Holocene)

Ponded sediments (Holocene and Pleistocene(?))

Young mixed alluvium and eolian deposits (Holocene and Pleistocene(?))

Young terrace-gravel deposits (Holocene and Pleistocene)

Young alluvial fan deposits (Holocene and Pleistocene)

Eolian cinder deposits (Holocene and Pleistocene)

Talus and rock fall deposits (Holocene and Pleistocene)

Landslide deposits (Holocene and Pleistocene)

Valley-fill deposits (Holocene and Pleistocene)

Old dune deposits, undivided (Pleistocene and Pliocene(?))

Old eolian sand sheet and dune deposits (Pleistocene and Pliocene(?))

Old mixed alluvium and eolian deposits (Pleistocene and Pliocene(?))

Older terrace-gravel deposits (Pleistocene and Pliocene(?))

Older alluvial fan deposits (Pleistocene and Pliocene)

Oldest terrace-gravel deposits (Pliocene and Miocene)

VOLCANIC ROCKS

[See table 1 in pamphlet for specific ages of volcanic rocks in the map area]

Volcanic rocks of the San Francisco Volcanic Field (Pleistocene, Pliocene, and 

Miocene)

Basalt flow of Merriam Crater (Pleistocene; Brunhes age)

Pyroclastic deposits of S P Mountain (Pleistocene; Brunhes age)

Basaltic andesite flow of S P Mountain (Pleistocene; Brunhes age)

Pyroclastic deposits of five young cinder cones (Pleistocene; Brunhes age)

Basalt flow of five young cinder cones (Pleistocene; Brunhes age)

Pyroclastic deposits of Shadow Mountain (Pleistocene; Brunhes age)

Basalt flows of Shadow Mountain (Pleistocene; Brunhes age)

Pyroclastic deposits (Pleistocene; Brunhes age)

Basalt flows (Pleistocene; Brunhes age)

Basalt flow of Tappan Wash (Pleistocene; Brunhes age)

Fissure deposits of Lockett Tank (Pleistocene; Brunhes age)

Pyroclastic deposits (Pleistocene; Brunhes or Matuyama age)

Basalt flows (Pleistocene; Brunhes or Matuyama age)

Pumice of San Francisco Mountain (Pleistocene; Matuyama age)

Basalt dike (Pleistocene; Matuyama age)

Pyroclastic deposits (Pleistocene; Matuyama age)

Basalt flows (Pleistocene; Matuyama age)

Basalt flow of Lava Point (Pleistocene; Matuyama age)

Rhyolite dome complex of Slate Mountain (Pleistocene; Matuyama age)

Basalt flows of Woodhouse Mesa (Pleistocene; Matuyama age)

Intrusive dike or plug (Pleistocene(?) or Pliocene; Matuyama age)

Pyroclastic deposits (Pleistocene(?) or Pliocene; Matuyama age)

Basalt flows (Pleistocene(?) or Pliocene; Matuyama age)

Basalt and andesite pyroclastic deposits (Pleistocene(?) or Pliocene; Matuyama 

age)

Basalt and andesite flows (Pleistocene(?) or Pliocene; Matuyama age)

Dike in amphitheater (Pliocene; Gauss or Gilbert age)

Pyroclastic deposits (Pliocene; Gauss or Gilbert age)

Basalt flows (Pliocene; Gauss or Gilbert age)

Black Point Basalt flows (Pliocene)

Basalt flow of Cedar Ranch Mesa (Miocene)

SEDIMENTARY ROCKS

Oldest stream-channel deposits (Pliocene(?) and Miocene)

Mancos Shale (Upper Cretaceous)

Dakota Sandstone (Upper Cretaceous)

Entrada Sandstone-Cow Springs Sandstone, undivided (Middle Jurassic)

Glen Canyon Group (Lower Jurassic and Upper Triassic(?))

Navajo Sandstone (Lower Jurassic)

Kayenta Formation-Navajo Sandstone transition zone (Lower Jurassic)

Kayenta Formation (Lower Jurassic)

Moenave Formation (Lower Jurassic and Upper Triassic(?))

Chinle Formation (Upper Triassic)

Owl Rock Member

Petrified Forest Member

Shinarump Member and sandstone and siltstone member, undivided

Moenkopi Formation, undivided (Middle(?) and Lower Triassic)

Moenkopi Formation

Holbrook and Moqui Members, undivided (Middle(?) and Lower Triassic)

Shnabkaib Member and lower massive sandstone member, undivided (Lower 

Triassic)

Wupatki Member (Lower Triassic)

Kaibab Formation, undivided (Lower Permian)

Kaibab Formation

Harrisburg Member (Lower Permian)

Fossil Mountain Member (Lower Permian)

Toroweap Formation, undivided (Lower Permian)

Coconino Sandstone and Schnebley Hill Formation, undivided (Lower Permian)

Hermit Formation (Lower Permian)

Supai Group (Lower Permian, Pennsylvanian, and Upper Mississippian)

Esplanade Sandstone (Lower Permain)

Wescogame (Upper Pennsylvanian), Manakacha (Middle Pennsylvanian), and 

Watahomigi (Lower Pennsylvanian and Upper Mississippian) Formations, 

undivided

Redwall Limestone, undivided (Upper and Lower Mississippian)

Temple Butte Formation (Upper and Middle Devonian)

Tonto Group (Middle and Lower(?) Cambrian)

Muav Limestone (Middle Cambrian)

Bright Angel Shale (Middle Cambrian)—Shown only in cross section

Tapeats Sandstone (Middle and Lower(?) Cambrian)—Shown only in cross 

section

Crystalline rocks, undivided (Paleoproterozoic)—Shown only in cross section

Contact—Contacts between all alluvial and eolian units are approximate and arbitrary

Fault—Dashed where inferred or approximately located; dotted where concealed; bar 

and ball on downthrown side. Number is estimated fault separation in meters

Fracture—Open fracture (0.5 to 3.5 m wide) without offset

Offset fracture—Open fracture (0.5 to 3.5 m wide) with offset (generally less than 1.5 

m)

Folds—Showing trace of axial surface and direction of plunge; dashed where approximately located; dotted where concealed

Anticline

Plunging anticline

Syncline

Plunging syncline

Monocline

Dome

Strike and dip of beds

Inclined—Measured in the field

Implied—Interpreted from aerial photographs; dip amount not determined

Strike of vertical and subvertical joints—Interpreted from aerial photographs; 

symbol placed where joints are most visible on aerial photographs

Collapse structure—Black dot shows circular collapse structure characterized by 

strata dipping inward toward a central point. Magenta dot shows circular collapse 

structure characterized by strata dipping inward toward central point and 

brecciated rock

Sinkhole—Enclosed depression or cave. Sinkholes breached by drainages are not 

shown

Volcanic vent

Uranium mine

Flow direction of basalt

Figure 1. View looking southeast toward Black Point (A) and the Black Point Monocline 

(B). The 2.4 Ma Black Point basalt flow (Tbpb) came down a tributary (C) at upper right 

edge of the photo and spread downstream into the Little Colorado River bed towards the 

viewer. The hummocky terrain below the basalt flow is landslide debris (Ql) consisting of 

basalt blocks and underlying Chinle Formation mudstone. Photograph courtesy of Michael 

Collier, Flagstaff, Arizona, 1996.

Figure 4. View looking north at the cinder cone and basalt flow of S P Mountain (Qyap). The cone 

is 287 m (940 ft) high; the interior crater is 60 m (200 ft) deep. S P volcano erupted 71,000 years 

ago. Two lobes of the associated basalt (Qyab) flowed into a nearby graben structure (A). Photograph courtesy of Michael Collier, Flagstaff, Arizona, 1998.

Figure 2. View looking upstream (southeast) at the 0.5 Ma 

basalt flow of Tappan Wash (Qbt) downstream of Cameron, 

Arizona (A). The basalt originated from a source 88 km (55 mi) 

south of Cameron, then flowed another 11 km (7 mi) down the 

Little Colorado River. The river has since eroded bedrock on 

both sides of the basalt flow creating an inverted valley. Photograph courtesy of Michael Collier, Flagstaff, Arizona, 1996.

Figure 3. View looking northeast of the Little Colorado River 

Valley. In the foreground, Quaternary climbing sand dunes 

(Qd) meet the Red Rock Cliffs (Jm). In the distance, the Adeii 

Eechii Cliffs (Jn) form the southwestern edge of the Moenkopi 

Plateau. Photograph courtesy of Michael Collier, Flagstaff, 

Arizona, 2004.

A

A

C

B

A

C’

C

B

B’

A’

A

11 / ° 1 2

MAGNETIC 

NORTH

APPROXIMATE MEAN

DECLINATION, 2007 TRUE NORTH

Little Colorado River Gorge showing Paleozoic strata, Mississippian 

(bottom) to Permian (top). (Photograph by Susan S. Priest, 2007)