U.S. Department of the Interior Prepared In Cooperation With The Scientific Investigations Map 3268 U.S. Geological Survey National Park Service, U.S. Forest Service, Bureau of Land Management, and Navajo Nation Sheet 3 of 3 Pamphlet accompanies map CORRELATION OF MAP UNITS SURFICIAL DEPOSITS
QsQaf Qf QdQesQdl Qdp Qdb Qdm Qdlu Qg1 Qa1 Qg2 Qa2 Qps Qae Qg3 Qa3 Holocene Qv Qtr Ql QUATERNARY LIST OF MAP UNITS SEDIMENTARY ROCKS Supai Group (Cisuralian, Pennsylvanian, and Upper Mississippian) Qg4 Pleistocene [Some map units are too small to distinguish unit identification by color. These units are labeled Qa4 Qg5-18 Km Mancos Shale (Upper Cretaceous) Pe Esplanade Sandstone (Cisuralian) Pliocene where possible; all units are attributed in the geodatabase] Tgs TERTIARY Miocene Kd Dakota Sandstone (Upper Cretaceous) ms Wescogame (Upper Pennsylvanian), Manakacha (Middle Pennsylvanian) SURFICIAL DEPOSITS SEDIMENTARY ROCKS and Watahomigi (Lower Pennsylvanian and Upper Mississippian) Forma- Qaf Artificial fill and quarries (Holocene) Morrison Formation (Upper Jurassic) tions, undivided Km Upper Jms Salt Wash Member Ms Surprise Canyon Formation (Upper Mississippian) CRETACEOUS Qs Stream-channel deposits (Holocene) Kd Cretaceous San Rafael Group (Middle Jurassic) Jr Romana Sandstone Mr Redwall Limestone, undivided (Upper and Lower Mississippian) Unconformity Qf Floodplain deposits (Holocene) Jms Je Entrada Sandstone Upper Jurassic Qes Sand sheet deposits (Holocene) Unconformity Jc Carmel Formation, undivided Qd Dune sand and sand sheet deposits, undivided (Holocene) EXPLANATION OF MAP SYMBOLS Jr Jcu Paria River Member and Winsor Member, undivided Unconformity Qdl Linear dune deposits (Holocene) Contact—Contacts between all alluvial and eolian units are approximate and Je Jcj Judd Hollow Tongue and Page Sandstone Tongues, undivided Qdp Parabolic dune deposits (Holocene) arbitrary San
Rafael Middle Jurassic Jp Page Sandstone 35 F Qdb Barchan dune deposits (Holocene) Fault—Dashed where inferred; dotted where concealed; bar and ball on down- Group Jcu Glen Canyon Group (Lower Jurassic) thrown side. Showing fault offset in feet Qdm Jn Navajo Sandstone Unconformity Jc JURASSIC Mixed dune deposits (Holocene) Folds—Showing trace of axial surface and direction of plunge; dotted where Jk Kayenta Formation, undivided Jcj Jp Qdlu Linear dune and sand sheet deposits, undivided (Holocene) location is concealed Anticline Unconformity Qg1 Young terrace-gravel deposits (Holocene) Jks Springdale Sandstone Member F ? Jn Jm F Plunging anticline Qa1 Young alluvial fan deposits (Holocene) Moenave Formation and Wingate Sandstone, undivided Jk Chinle Formation (Upper Triassic) Glen M Syncline Qg2 Intermediate terrace-gravel deposits (Holocene) co Owl Rock Member Canyon Jks Lower Jurassic Group M ? Plunging syncline Unconformity Qa2 Intermediate alluvial fan deposits (Holocene) cp Petrified Forest Member Jm Monocline Qps Ponded sediments (Holocene) cs Shinarump Member Unconformity Moenkopi Formation (Middle(?) and Lower Triassic) Strike and dip of beds Qae o Mixed alluvium and eolian deposits (Holocene) Upper red member (Middle(?) and Lower Triassic) co mu 35 Inclined—Showing dip measured in the field
Upper Qg3 o cp Old terrace-gravel deposits (Holocene) Shnabkaib Member (Lower Triassic) Triassic ms Implied—Interpreted from aerial photographs; dip not determined cs Qa3 Old alluvial fan deposits (Holocene) Lower red member, Virgin Limestone Member, and middle red member, TRIASSIC mlm Strike of vertical and subvertical joints—Interpreted from aerial photographs; Unconformity undivided (Lower Triassic) Qv Valley-fill deposits (Holocene and Pleistocene(?)) symbol placed where joints are most visible on aerial photographs Kaibab Formation (Cisuralian) mu Middle(?) and Lower Triassic Qtr Talus and rock-fall deposits (Holocene and Pleistocene(?)) Pkh Harrisburg Member Collapse structure—Black dot shows circular collapse structure characterized by ms strata dipping inward toward a central point. Magenta dot shows circular Lower Triassic Ql Pkf Fossil Mountain Member collapse structure characterized by strata dipping inward toward a central point mlm Landslide deposits (Holocene and Pleistocene) and brecciated rock Toroweap Formation, undivided (Cisuralian) Unconformity Qg4 Older terrace-gravel deposits (Pleistocene) Pt Sinkhole Pkh Qa4 Older alluvial fan deposits (Pleistocene and Pliocene(?)) Pc Coconino Sandstone (Cisuralian) Mine or prospect Pkf Qg5-18 Oldest terrace-gravel deposits, undivided (Pleistocene and Pliocene(?)) Ph Hermit Formation (Cisuralian) Unconformity Fracture—Open fracture (0.5 to 3.5 m wide) without offset Tgs Gravel and sedimentary deposits (Pliocene(?) or Miocene(?)) Pt Offset fracture—Open fracture (0.5 to 3.5 m wide) with offset (generally less than 1.5 m Unconformity Cisuralian PERMIAN Pc
Unconformity
Ph
Unconformity 111°37'30'' Pe Supai Unconformity Group Upper, Middle and Lower Pennsylvanian A B Ms PENNSYLVANIAN and Upper Mississippian Unconformity Qg6 Qg5 111°30' MISSISSIPPIAN Qg5 Ms Upper Mississippian Qg5 Qg14 37°00' 36°52'30'' Qg12 Upper and Lower Qg6 Qg13 Qg12 Qg12 Mr Qg10 Qg9 Qg11 Mississippian Qg8 Qg6 Qg16 Qg10 Qg10 Qg9 Qg5 Qg14 Qg13 Qg16 Qg9 Qg12 Qg11 Qg10 Qg10 Qg10 Qg13 Qg12 Qg10 Qg5 Qg14 Qg14 Qg6 Qg11 Qg5 Qg13 Qg11 111°00' Qg5 Qg14 112°00' Qg6 Qg14 Qg10 37°00' Cummings Qg5 Qg15 Cedar Qg7 GLEN CANYON Mesa Qg5 Qg5 Mountain 89 Qg15 NRA Qg11 Qg7 Qg6 Qg10 RAINBOW PLATEAU Qg7 Table 1. Age and elevation of floodplain and terrace-gravel deposits along the Colorado Qg6 Qg12 Qg7 Qg7 Qg7 River from Glen Canyon Dam to Badger Rapids, a 25 mile (40 km) section of the river. Qg13 Qg10 Qg12 Ferry Swale Glen Qg7 Qg15 Qg12 Qg18 Paria River Canyon Refer to locations of separate older terrace-gravel deposits in figure 2. Qg17 Dam Page Qg8 Qg7 Qg16 Qg11 Qg7 Qg7 Elevation above Map unit Age Qg6 PARIA PLATEAU Colorado River Qg6 Qg9 Qg11 Lees Ferry Floodplain deposits Qg9 Qg9 VERMILION CLIFFS STRIP LeChee 2B LeChee Rock Navajo Creek Marble Qf Holocene 0–45 ft (0–14 m) Qg9 NATIONAL MONUMENT Canyon Young and intermediate terrace-gravel deposits Qg9 COW SPRINGS Qg9 Qg18 Vermilion Qg1 Holocene 7–17 ft (2–5 m) Qg9 Cliffs Lodge SYNCLINE Tse Esgizii Butte Qg2 Holocene 27–47 ft (8–14 m) Qg9a Qg18 Qg10 Cliffs Qg3 Holocene 47–77 ft (14–23 m) Echo Qg9a Qg10 Qg9a Qg4 Holocene and Pleistocene(?) 87–127 ft (27–39 m) Qg10 Cliff Qg9a Vermilion Dwellers Lodge Older terrace-gravel deposits Qg9a Kaibito Qg5 PARIA PLATEAU SYNCLINE 2A Holocene and Pleistocene(?) 107–127 ft (33–39 m) Qg9a KAIBITO Qg11 Qg6 Holocene(?) and Pleistocene 147–207 ft (45–63 m) Qg9a 98 Qg9a 89A Qg7 Pleistocene 275–300 ft (84–91 m) NAVAJO INDIAN
Creek Qg8 Pleistocene 290–390 ft (88–119 m) RIDGE
RED LAKE
ANTICLINE RESERVATION MONOCLINE House Rock Valley LIMESTONE Qg9 Pleistocene 495–555 ft (151–169 m)
PLATEAU SYNCLINEKAIBITO Qg9a Pleistocene 620–635 ft (189–194 m) Bitter Springs Copper Mine Qg10 Pleistocene 600–620 ft (183–189 m) Qg13 LAST TUBA CITY Qg11 Pleistocene 620–630 ft (189–192 m) CHANCE SYNCLINE Cliffs Kaibito Qg15 ARIZONA ANTICLINE Qg12 Pleistocene 760–800 ft (232–244 m) Qg13 Pleistocene 800–860 ft (244–262 m) Qg15
PRESTON MESA White Qg14 Pleistocene 900–920 ft (274–280 m) Qg15 GRAND CANYON ANTICLINE Colorado River Mesa 36°52'30'' NATIONAL PARK MARBLE PLATEAU F Qg15 Pleistocene 960–980 ft (293–299 m) 36°45' 89 ECHO CLIFFS Qg16 Pleistocene and Pliocene(?) 990–1,000 ft (302–305 m) MONOCLINE F Qg17 Pleistocene and Pliocene(?) 1,060–1,085 ft (323–331 m)
FENCE EMINENCE FAULTF BREAK FAULT Qg18 Pleistocene and Pliocene(?) 1,140–1,190 ft (347–363 m) 36°30' Figure 1. Map of the Glen Canyon Dam 30’ x 60’ quadrangle showing cultural and physiographic features as well as major geologic structures. Boxes define area of maps in figure 2.
Figure 2. Maps showing detail of terrace gravels (units Qg5-Qg18) along the Colorado River. A. Gravels from Lees Ferry south to River Mile 9 below Badger Rapid. Colorado River elevation at Lee’s Ferry is 3,133 ft (955 m). B. Gravels from northeast of Lees Ferry north to lower Lake Powell. Colorado River elevation at base of Glen Canyon Dam is 3,146 ft (959 m). River gradient between Glen Canyon Dam and River Mile 9 is 3.5 ft/mi. See table 1 for additional unit information. See figure 1 for map locations.
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 Geologic Map of the Glen Canyon 30’ x 60’ Quadrangle, Coconino County, Northern Arizona This map was printed on an electronic plotter directly from digital files. Dimensional calibration may vary between electronic plotters and between X and Y directions on the same plotter, and paper may change size due to atmospheric conditions; therefore, scale and proportions may not be true on plots of this map. For sale by U.S. Geological Survey, Information Services, Box 25286, Federal Center, Denver, CO 80225, By 1–888–ASK–USGS Digital files available at http://pubs.usgs.gov/sim/3268/ George H. Billingsley and Susan S. Priest Suggested Citation: Billingsley, G.H. and Priest, S.S., 201x, Geologic map of the Glen Canyon Dam 30’ x 60’ quadrangle, Coconino County, northern Arizona: U.S. Geological Survey Scientific Investigations 2013 Map 3268, pamphlet 43 p., 3 sheets, scale 1:50,000 (http://pubs.usgs.gov/sim/3268/).