geologic map of the kolob reservoir quadrangle, washington and

UTAH GEOLOGICAL SURVEY
a divison of
Utah Department of Natural Resources
in cooperation with
National Park Service
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Utah Geological Survey, 1594 W. North Temple,
P.O. Box 146100, Salt Lake City, Utah 84114-6100.
Phone: 801-537-3300; fax 801-537-3400;
www.geology.utah.gov
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Campground
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Rim
Horse Pasture
P l a t e a u Qac
Key access roads, selected trails, and prominent
features in and near Zion National Park shown in
brown. Condition and status of roads and trails
may change over time. Some not shown. From
data provided by National Park Service.
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il
Tra
For use at 1:24,000 scale only. The UGS does not
guarantee accuracy or completeness of data.
0
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Fieldwork by author in 2000-01
Project Manager: Grant C. Willis
GIS Analyst: Kent D. Brown
Cartographer: James W. Parker
ISBN 1-55791-739-6
1 KILOMETER
CONTOUR INTERVAL 40 FEET
NATIONAL GEODETIC VERTICAL DATUM OF 1929
TH
NOR
N E T IC
TRUE NORTH
12°27'
MAG
Although this product represents the work of
professional scientists, the Utah Department of Natural
Resources, Utah Geological Survey, makes no
warranty, expressed or implied, regarding its suitability
for a particular use. The Utah Department of Natural
Resources, Utah Geological Survey, shall not be liable
under any circumstances for any direct, indirect,
special, incidental, or consequential damages with
respect to claims by users of this product.
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SCALE 1:24,000
This geologic map was funded by the Utah Geological
Survey and the U.S. Department of the Interior,
National Park Service. The views and conclusions
contained in this document are those of the author
and should not be interpreted as necessarily
representing the official policies, either expressed or
implied, of the U.S. Government.
660
Base from U.S. Geological Survey,
Kolob Reservoir 7.5' quadrangle, 1980
Shaded topography generated from digital elevation data
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N AT I O N A L
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Mountain
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Langston
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Bear
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Plate 1
Utah Geological Survey Map 220
Geologic Map of the Kolob Reservoir Quadrangle
APPROXIMATE MEAN
DECLINATION, 2007
GEOLOGIC MAP OF THE KOLOB RESERVOIR QUADRANGLE,
WASHINGTON AND IRON COUNTIES, UTAH
by
Robert F. Biek
2007
UTAH
QUADRANGLE LOCATION
See plate 2 references for geologic map list
Utah Geological Survey
a division of
Utah Department of Natural Resources
in cooperation with
National Park Service
Plate 2
Utah Geological Survey Map 220
Geologic Map of the Kolob Reservoir Quadrangle
Qmsh
Qmsy
Qmso
Qmso
(Kd)
Qmt
Qac
Qaco
Qae
Qer
Mixed-environment deposits
Jcw
Alluvial and eolian deposits (Holocene to upper Pleistocene) – Locally
derived, fine- to coarse-grained sand and silt with subangular to angular
gravel; deposited in topographic depressions by small streams, slope
wash, and wind; includes small alluvial fans and colluvium along
margins of deposits; 0 to 20 feet (0-6 m) thick.
Jcp
Eolian and residual deposits (Holocene to upper Pleistocene) – Reddishorange, fine- to medium-grained sand with residual Navajo Sandstone
pebbles, cobbles, and boulders; forms irregular sheets on top of the
Navajo Sandstone, from which it is derived, in the southwest corner
of the quadrangle; generally less than 3 feet (1 m) thick.
Jcx
Residual deposits
Qrlc
Residual deposits (Holocene to lower[?] Pleistocene) – Residual lag of
angular to subangular basalt blocks derived from the Little Creek Peak
lava flow, which is preserved in place on the ridge to the west; includes
very rare blocks of Dakota Formation sandstone; although Little Creek
Peak basalt is virtually the only rock type seen in this unit, nowhere
is it clearly in place; probably represents a lag of basalt let down by
erosion of underlying beds, but may represent a flow that cascaded
southeastward from the adjacent ridge; thickness uncertain, but probably
as much as several tens of feet thick.
Qst
Spring tufa (Holocene) – Light-gray to light-brownish-gray, porous,
calcareous tufa characterized by a sponge-like network of cavities;
mapped at Birch Spring, about 2 miles (3 km) northwest of Kolob
Reservoir; 0 to about 20 feet (0-6 m) thick.
Jccu
Volcanic rocks
Jccl
Qbg
Qbhpc
Qbhp
Qbkpc
Qbkp
Qblpc
Qblp
Qblc
Hornet Point lava flow and cinder cone (middle Pleistocene) – Mediumto dark-gray, medium- to coarse-grained olivine basalt to trachybasalt
lava flow containing abundant pyroxene phenocrysts; locally deeply
weathered to gruss-like soils; boulders typically have concentric
weathering rinds; erupted from vent at deeply eroded cinder cone
(Qbhpc) at Hornet Point; yielded 40Ar/39Ar isochron age of 0.74 ±
0.05 Ma from sample CP83100-3 in the Cogswell Point quadrangle
(Biek and Hylland, 2007); lava flow is as much as 240 feet (73 m)
thick in this quadrangle.
Jts
Kolob Peak lava flow and cinder cone (lower Pleistocene) – Mediumto light-gray, fine-grained olivine basaltic trachyandesite lava flow;
forms densely vegetated dip slope on the east side of Kolob Peak;
erupted from vent at Kolob Peak, a cinder cone (Qbkpc) now eroded
nearly in half; sample KR81200-1 yielded 40Ar/39Ar plateau age of
1.05 ± 0.05 Ma; thickness uncertain, but likely in excess of 100 feet
(30 m) thick where it fills paleodrainages.
Jn
Lava Point lava flow and cinder cones (lower Pleistocene) – Light- to
medium-gray, fine- to medium-grained olivine basaltic trachyandesite
to borderline basaltic andesite and trachybasalt lava flow; query indicates
uncertain correlation near Blue Springs Reservoir; erupted from vents
at Home Valley Knoll, a group of three overlapping cinder cones
(Qblpc); yielded 40Ar/39Ar plateau ages of 1.02 ± 0.03 Ma (sample
ZP-0601) and 1.08 ± 0.02 Ma (sample ZP-0602) for this flow at Lava
Point, consistent with several published K-Ar and 40Ar/39Ar ages (Best
and others, 1980; Hamblin and others, 1981; Willis and Hylland, 2002);
as much as 120 feet (37 m) thick where it fills paleodrainages.
Little Creek Peak lava flow (lower Pleistocene) – Medium-gray, fineto medium-grained olivine basalt; locally caps ridge south of Little
Creek Peak, and a basalt lag (Qrlc) derived from this flow covers the
slope to the southeast of Little Creek Peak; yielded 40Ar/39Ar plateau
age of 1.44 ± 0.04 Ma from sample VR43-01 in The Guardian Angels
quadrangle (Willis and Hylland, 2002); source unknown; 0 to 30 feet
(0-9 m) thick.
0-240 (0-73)
0.74 ± 0.05 Ma (Qbhp)
Kolob Peak flow and cinder cone
Qbkp,Qbkpc 0-100 (0-30)
1.05 ± 0.05 Ma ((Qbkp)
Lava Point flow and cinder cones
Qblp,Qblpc,Qblp? 0-120 (0-37)
H. SERIES
Pleistocene
QUATERNARY
upper
T.
middle
Qbhp,
Qbhpc
Mio.
Little Creek Peak flow
Qblc
0-30 (0-9)
Old boulder gravel deposits
Ta
0-30 (0-9)
upper unit
Ksu
320+ (100+)
Tibbet Canyon
Member
Kst
240-450
(75-135)
Qblp
Qbkp:
Qblp? Qbkp 1.05 ± 0.05 Ma
unconformity
Miocene
Ta
Upper
Qblp:
1.02 ± 0.03 Ma
1.08 ± 0.02 Ma
Numerous landslides
Gastropods, coal
Two prominent sandstone beds
Craginia sp. gastropods
Coal
Dakota Formation
850 (260)
Kd
unconformity
Coal
KJu
Poorly exposed
Numerous landslides
Kst
L.
Kd
Cedar Mountain conglomerate member
Formation
Kcmc
0-35 (0-11)
Jcw
240-320
(73-98)
unconformity
Kcmc
Winsor Member
KJu
Middle
Jccu
50-160
(15-48)
Crystal Creek Member
Jcx
150-250
(45-75)
upper
Jccu
100-140
(30-43)
Poorly vegetated
lower
Jccl
240-380
(73-115)
Well vegetated
White Throne Member
Jtw
0-130 (0-40)
J-2 unconformity
Pinches out westward
Sinawava Member
Jts
10-40 (3-12)
J-1 unconformity
Co-op Creek
Limestone
Member
J-2 unconformity
Jtw
Structure contour on top of Navajo Sandstone
(south and west part of map) and on top of
Tibbet Canyon Member (northeast part of
map); contour interval 100 feet; short dash
where projected, long dash where control is
poor
Jts
J-1 unconformity
Jn
Jku
"Chippy" limestone
Jcp
Alabaster gypsum
Isocrinus sp.
Normal fault, dashed where approximately
located, dotted where concealed; bar and
ball on downthrown side
Jccl
Pebbly conglomerate
K unconformity
Paria River Member
Carmel
Formation
Contact, dashed where approximately located
Jcx
Temple Cap
Formation
Major joint
Jks
unconformity
JTRm
J-0 unconformity
TRc
TR-3 unconformity
Middle
and
Lower
Landslide or slump scarp, hachures on downdropped side
2
Approximate strike and dip of inclined bedding
determined photogrammetrically
Vertical cliffs
Large, sweeping crossbeds
Navajo Sandstone
Jn
Joint, near vertical
2100-2200
(640-670)
TRm
Pit - sand and gravel (no letter), cinders (c)
Quarry
Spring
Paria River Member (Middle Jurassic) – Laminated to very thin
bedded, light-gray argillaceous limestone and micritic limestone that
locally overlies a thick, white, alabaster gypsum bed common in the
basal part of the Paria River Member; limestone weathers to small
chips and plates and locally contains small pelecypod fossils; forms
steep, ledgy slopes; upper contact is sharp and planar; deposited in
shallow-marine and coastal-sabkha environments (Imlay, 1980;
Blakey and others, 1983); about 50 to 160 feet (15-48 m) thick.
Planar bedded, sabkha
environment
Volcanic vent
Collapse feature (sinkhole)
Crystal Creek Member (Middle Jurassic) – Thin- to medium-bedded,
reddish-brown gypsiferous siltstone, mudstone, and very fine to
medium-grained sandstone; typically friable and weakly cemented
with gypsum; forms vegetated, poorly exposed slopes; upper contact
is sharp and broadly wavy and corresponds to the base of a thick
Paria River gypsum bed or argillaceous limestone interval; deposited
in coastal-sabkha and tidal-flat environments (Imlay, 1980; Blakey
and others, 1983); about 150 to 250 feet (45-75 m) thick.
KR81100-1
upper unit
Jku
700-1000
(210-300)
Springdale Sandstone
Member
Jks
100-150
(30-45)
Moenave Formation, undivided
JTRm
200-350
(60-105)
Chinle Formation, undivided
TRc
450-650
(135-200)
Moenkopi Formation, undivided
TRm
1700-1800
(520-550)
Kayenta
Formation
Sample location and number
ACKNOWLEDGMENTS
I appreciate the assistance of Dave Sharrow, National Park Service, who helped coordinate this mapping project. Pete Rowley, Geologic Mapping Inc., and Grant Willis and
Mike Hylland, both with the Utah Geological Survey (UGS), provided constructive reviews of this map. Gary Christenson, Sandy Eldredge, Hugh Hurlow, and Dave Tabet, each
with the UGS, also reviewed parts of this map. Thanks to Jim Kirkland for identifying Cretaceous gastropods and for sharing his knowledge of the Cretaceous strata of southwest
Utah. Kent Brown (UGS) provided photogrammetric support and GIS digital cartography. Bill McIntosh and his colleagues at the New Mexico Geochronology Research Laboratory
provided 40Ar/39Ar analyses.
Selected geologic maps available for the Zion National Park area
In addition to the 1:24,000-scale geologic quadrangle maps listed below, Hamilton (1978) provided a 1:31,680-scale geologic map of Zion National Park. See index map on
plate 1 for quadrangle locations.
Upper unit – Thin- to medium-bedded, light-gray micritic limestone;
locally oolitic and sandy; forms sparsely vegetated, ledgy slopes
and cliffs; upper contact is sharp and planar; about 100 to 140 feet
(30-43 m) thick.
Cedar Mountain
Clear Creek Mountain
Cogswell Point
Elephant Butte
Hildale
Kanarraville
Little Creek Mountain
Navajo Lake
Kolob Arch
Smith Mesa
Lower unit – Mostly thinly laminated to thin-bedded, light-gray
calcareous shale and platy limestone; forms steep, vegetated slopes;
contact with upper unit is gradational and corresponds to a subtle
break in slope and vegetation patterns; about 240 to 380 feet (73115 m) thick.
White Throne Member (Middle Jurassic) – Very thick bedded,
yellowish-gray to pale-orange, well-sorted, fine-grained quartz
sandstone with large high-angle cross-beds similar to the Navajo
Sandstone; upper contact is sharp and planar; deposited in coastal
dune field (Blakey, 1994; Peterson, 1994); pinches out westward
under the Upper Kolob Plateau due to truncation beneath the J-2
unconformity; 0 to 130 feet (0-40 m) thick.
Averitt (1962)
Hylland (2000)
Biek and Hylland (2007)
Sable and Doelling (1990)
Sable (1995)
Averitt (1967)
Hayden (2004)
Moore and others (2004)
Biek (2007)
Sable and others (in prep.)
Smithsonian Butte
Springdale East
Springdale West
Straight Canyon
Temple of Sinawava
The Barracks
The Guardian Angels
Virgin
Webster Flat
Moore and Sable (2001)
Doelling and others (2002)
Willis and others (2002)
Cashion (1967), Sable and Hereford (2004)
Doelling (2002)
Sable and Doelling (1993)
Willis and Hylland (2002)
Hayden (in preparation)
Doelling and Graham (1972)
Shown on cross section only
Kst
Sinawava Member (Middle Jurassic) – Interbedded, slope-forming,
moderate-reddish-brown mudstone, siltstone, and very fine grained
silty sandstone; forms narrow, but prominent, deep-reddish-brown,
vegetated slope at the top of the Navajo Sandstone; upper contact
is gradational and interfingering with the White Throne Member,
and, in western exposures, unconformable with light-gray calcareous
shale and micritic limestone of the Co-op Creek Limestone Member;
deposited in coastal-sabkha and tidal-flat environments (Blakey,
1994; Peterson, 1994); about 10 to 40 feet (3-12 m) thick.
Kst
Kd
Navajo Sandstone (Lower Jurassic) – Moderate-reddish-orange to
moderate-orange-pink, massively cross-bedded, poorly to moderately
well-cemented sandstone that consists of well-rounded, fine- to mediumgrained, frosted quartz; contains few planar interdune deposits of
sandstone and siltstone; forms spectacular, sheer cliffs and is locally
prominently jointed; upper, unconformable contact is sharp and planar
and corresponds to a prominent break in slope, with cliff-forming,
cross-bedded sandstone below and reddish-brown mudstone above;
corresponds to the "pink Navajo" and "brown Navajo" of Willis and
Hylland (2002); deposited in a vast coastal and inland dune field with
prevailing winds principally from the north (Blakey, 1994; Peterson,
1994); lower few hundred feet is characterized by planar sandstone
beds and represents deposition in a sand-dominated sabkha environment
(Tuesink, 1989; Sansom, 1992); about 2100 to 2200 feet (640-670 m)
thick.
Ta
Above: View northwest to old boulder gravel deposits (Ta) along the east side of Kolob
Reservoir. These deposits are characterized by very large boulders of quartz monzonite as
much as 24 feet (7.3 m) long, 22 feet (6.7 m) wide, and at least 8 feet (2.4 m) high, and
quartz monzonite boulders 10 to 15 feet (3-5 m) long are common as shown in the
accompanying photo. These deposits also contain abundant smaller quartz monzonite
boulders, and cobbles and small boulders derived from Cretaceous fossiliferous sandstone,
the Carmel Formation, and Claron limestone, as well as recycled, rounded pebbles and
small cobbles of Precambrian and Cambrian quartzite. These old boulder gravels likely
represent Miocene-age debris-flow deposits shed off the ancestral Pine Valley Mountains,
prior to development of the Hurricane fault. Boulders of the one-million-year-old Horse
Ranch Mountain lava flow are locally incorporated into these deposits, but the mechanism
by which they became incorporated into the deposits remains unclear.
Left: The hill in the distance is capped by the Tibbet Canyon Member of the Straight
Cliffs Formation (Kst), which overlies the Dakota Formation (Kd).
Marzolf (1994) and Blakey (1994) presented evidence to restrict the
Moenave Formation to the Dinosaur Canyon and Whitmore Point
Members, with a major regional unconformity at the base of the
Springdale Sandstone. Further work supports this evidence, indicating
that the Springdale Sandstone is more closely related to the Kayenta
Formation and should be made its basal member (see, for example,
Lucas and Heckert, 2001; Molina-Garza and others, 2003; Steiner,
2005). We anticipate that this change will be formalized, and so here
informally reassign the Springdale Sandstone as the basal member of
the Kayenta Formation.
Old boulder gravel deposits (Miocene?) – Poorly sorted, clay- to very
large boulder-size sediment characterized by very large quartz monzonite
boulders; clasts also include large boulders of Cretaceous fossiliferous
sandstone, cobbles and small boulders derived from the Carmel
Formation, recycled, rounded pebbles and small cobbles of Precambrian
and Cambrian quartzite, and uncommon cobbles and boulders of Claron
limestone; most clasts are subangular to subrounded, but the quartzite
clasts are well rounded; quartz monzonite boulders as much as 24 feet
(7.3 m) long, 22 feet (6.7 m) wide, and at least 8 feet (2.4 m) high are
present in the vicinity of Kolob Reservoir, and subspherical quartz
monzonite boulders 10 to 15 feet (3-5 m) long are common; most
quartz monzonite clasts, however, are 1.5 to 3 feet (0.5-1 m) in diameter;
forms a deeply eroded surface that drapes over pre-existing topography;
probably deposited by debris flows or possibly a gravity slide originating
in the ancestral Pine Valley Mountains; this hypothesis, however,
requires a complete eastward-to-westward reversal of drainage across
the Hurricane fault; Averitt (1962, 1964) first described similar deposits
farther north, east and southeast of Cedar City, and Anderson and
Mehnert (1979) interpreted those exposures as debris-flow deposits
shed off the ancestral Pine Valley Mountains; Hacker (1998) and
Hacker and others (2002) provided evidence that the Pine Valley
Mountains stood very high and shed gravity slides, volcanic rocks,
and debris flows about 20.5 million years ago, long before initiation
of the Hurricane fault; blocks of the Pine Valley laccolith caught in
the Hurricane fault zone (Biek, 2007) show that the laccolith once
likely reached east of the Hurricane fault, thus providing a somewhat
closer source for the large Pine Valley boulders; thickness uncertain,
but probably less than 30 feet (9 m) thick in this quadrangle; some
deposits may contain just a lag of widely scattered larger clasts over
poorly exposed bedrock, the matrix having been eroded away.
Two basalt boulders clearly incorporated into the deposits at Kolob
Reservoir (samples KR72000-5 and KR72000-6) have a chemical
signature similar to the Horse Ranch Mountain lava flow, and one
boulder (KR72000-6) yielded a maximum 40Ar/39Ar age of 0.97 ±
0.18 Ma, analytically indistinguishable from the 1.03 ± 0.06 Ma Horse
Ranch Mountain lava flow (Biek, 2007); how the basalt boulders came
to be incorporated into these assumed Miocene-age deposits is not
known.
Jku
Jks
REFERENCES
Anderson, R.E., and Mehnert, H.H., 1979, Reinterpretation of the history of the Hurricane
fault in Utah, in Newman, G.W., and Goode, H.D., editors, 1979 Basin and Range
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Averitt, Paul, 1962, Geology and coal resources of the Cedar Mountain quadrangle, Iron
County, Utah: U.S. Geological Survey Professional Paper 389, 72 p.
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Iron County, Utah: Geological Society of America Bulletin, v. 75, p. 901-908.
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Cenozoic mafic volcanism, southwestern Utah and adjoining areas: American Journal of
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Biek, R.F., 2007, Geologic map of the Kolob Arch quadrangle and part of the Kanarraville
quadrangle, Washington and Iron Counties, Utah: Utah Geological Survey Map 217, 3
plates, scale 1:24,000.
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Washington, Kane, and Iron Counties, Utah: Utah Geological Survey Map 221, 2 plates,
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Biek, R.F., Willis, G.C., Hylland, M.D., and Doelling, H.H., 2003, Geology of Zion National
Park, Utah, in Sprinkel, D.A., Chidsey, T.C., and Anderson, P.B., editors, Geology of
Utah’s parks and monuments: Utah Geological Association and Bryce Canyon Natural
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of west-central United States: Denver, Colorado, Rocky Mountain Section of Society of
Economic Paleontologists and Mineralogists, p. 77-100.
Cashion, W.B., 1967, Geologic map of the south flank of the Markagunt Plateau, northwest
Kane County, Utah: U.S. Geological Survey Miscellaneous Geologic Investigations Map
I-494, 1 plate, scale 1:24,000.
Doelling, H.H., 2002, Interim geologic map of the Temple of Sinawava quadrangle, Washington
County, Utah: Utah Geological Survey Open-File Report 396, 13 p., 1 plate, scale 1:24,000.
Doelling, H.H., and Davis, F.D., 1989, The geology of Kane County, Utah – geology, mineral
Upper unit (Lower Jurassic) – Interbedded, thin- to very thick bedded,
moderate-reddish-brown siltstone, fine-grained sandstone, and
mudstone with planar, low-angle, and ripple cross-stratification;
contains several thin, light-olive-gray weathering, light-gray dolomite
beds; upper contact is conformable and gradational and corresponds
to the top of the highest thin siltstone and mudstone beds, above
which lie the towering cliffs of Navajo Sandstone; deposited in
fluvial, distal fluvial/playa, and minor lacustrine environments
(Tuesink, 1989; Sansom, 1992; Blakey, 1994; Peterson, 1994); only
upper few tens of feet of the formation is exposed in the quadrangle
at Hop Valley, but the entire upper unit is about 700 to 1000 feet
(210-300 m) thick.
Springdale Sandstone Member (Lower Jurassic) – Shown in cross
section only; about 100 to 150 feet (30-45 m) thick (Willis and
Hylland, 2002; Biek, 2007).
unconformity
JURASSIC AND TRIASSIC
JTRm
Moenave Formation, undivided (Lower Jurassic to Upper Triassic) –
Shown in cross section only; age from Lucas and others (2005); about
200 to 350 feet (60-105 m) thick (Willis and Hylland, 2002; Biek,
2007).
J-0 unconformity
TRIASSIC
TRc
Chinle Formation, undivided (Upper Triassic) – Shown in cross section
only; about 450 to 650 feet (135-200 m) thick (Willis and Hylland,
2002; Biek, 2007).
TR-3 unconformity
TRm
Moenkopi Formation, undivided (Middle to Lower Triassic) – Shown in
cross section only; about 1700 to 1800 feet (520-550 m) thick (Willis
and Hylland, 2002; Biek, 2007).
resources, geologic hazards: Utah Geological and Mineral Survey Bulletin 124, 192 p.,
10 plates, scale 1:100,000.
Doelling, H.H., and Graham, R.L., 1972, Southwestern Utah coal fields – Alton, Kaiparowits
Plateau, and Kolob-Harmony: Utah Geological and Mineral Survey Monograph Series
1, 333 p.
Doelling, H.H., Willis, G.C., Solomon, B.J., Sable, E.G., Hamilton, W.L., and Naylor, L.P.,
II, 2002, Interim geologic map of the Springdale East quadrangle, Washington County,
Utah: Utah Geological Survey Open-File Report 393, 20 p., 1 plate, scale 1:24,000.
Eardley, A.J., 1966, Rates of denudation in the High Plateaus of southwestern Utah: Geological
Society of America Bulletin, v. 77, p. 777-780.
Eaton, J.G., Laurin, Jiri, Kirkland, J.I., Tibert, N.E., Leckie, R.M., Sageman, B.B., Goldstrand,
P.M., Moore, D.W., Straub, A.W., Cobban, W.A., and Dalebout, J.D., 2001, Cretaceous
and early Tertiary geology of Cedar and Parowan Canyons, western Markagunt Plateau,
Utah, in Erskine, M.C., editor and Faulds, J.E., Bartley, J.M., and Rowley, P.D., co-editors,
The geologic transition, High Plateaus to Great Basin – a symposium and field guide, The
Mackin Volume: Utah Geological Association Publication 30 and Pacific Section American
Association of Petroleum Geologists Publication GB 78, p. 57-74.
Gustason, E.R., 1989, Stratigraphy and sedimentology of the middle Cretaceous (AlbianCenomanian) Dakota Formation, southwestern Utah: Boulder, Colorado, University of
Colorado, Ph.D. dissertation, 376 p.
Hacker, D.B., 1998, Catastrophic gravity sliding and volcanism associated with the growth
of laccoliths – an example from early Miocene hypabyssal intrusions of the Iron Axis
magmatic province, Pine Valley Mountains, southwest Utah: Kent, Ohio, Kent State
University, Ph.D. dissertation, 258 p.
Hacker, D.B., Holm, D.K., Rowley, P.D., and Blank, H.R., 2002, Associated Miocene laccoliths,
gravity slides, and volcanic rocks, Pine Valley Mountains and Iron Axis, southwestern
Utah, in Lund, W.R., editor, Field guide to geologic excursions in southwestern Utah and
adjacent areas of Arizona and Nevada: U.S. Geological Survey Open-File Report 02-172,
p. 235-283.
Hamblin, W.K., Damon, P.E., and Bull, W.B., 1981, Estimates of vertical crustal strain rates
along the western margins of the Colorado Plateau: Geology, v. 9, p. 293-298.
Hamilton, W.L., 1978 (revised 1987), Geological map of Zion National Park, Utah: Zion
Natural History Association, scale 1:31,680.
Hayden, J.M., 2004, Geologic map of the Little Creek Mountain quadrangle, Washington
County, Utah: Utah Geological Survey Map 204, 2 plates, scale 1:24,000.
—in preparation, Geologic map of the Virgin quadrangle, Washington County, Utah: Utah
Geological Survey Map, 2 plates, scale 1:24,000.
Hylland, M.D., 2000, Interim geologic map of the Clear Creek Mountain quadrangle, Kane
County, Utah: Utah Geological Survey Open-File Report 371, 12 p., 2 plates, scale
1:24,000.
Imlay, R.W., 1980, Jurassic paleobiogeography of the conterminous United States in its
continental setting: U.S. Geological Survey Professional Paper 1062, 134 p.
Kirkland, J.I., Britt, Brooks, Burge, D.L., Carpenter, Ken, Cifelli, Richard, Decourten, Frank,
Eaton, Jeffrey, Hasiotis, Steve, and Lawton, Tim, 1997, Lower to middle Cretaceous
dinosaur faunas of the central Colorado Plateau – a key to understanding 35 million years
of tectonics, sedimentology, evolution and biogeography, in Link, P.K., and Kowallis, B.J.,
editors, Mesozoic to recent geology of Utah: Brigham Young University Geology Studies,
v. 42, part 2, p. 69-103.
Laurin, Jiri, and Sageman, B.B., 2001, Tectono-sedimentary evolution of the western margin
of the Colorado Plateau during the latest Cenomanian and early Turonian, in Erskine,
M.C., editor and Faulds, J.E., Bartley, J.M., and Rowley, P.D., co-editors, The geologic
transition, High Plateaus to Great Basin – a symposium and field guide, The Mackin
Volume: Utah Geological Association Publication 30 and Pacific Section American
Association of Petroleum Geologists Publication GB 78, p. 57-74.
LeBas, M.J., LeMaitre, R.W., Streckeisen, A., and Zanettin, B., 1986, A chemical classification
of volcanic rocks based on the total alkali-silica diagram: Journal of Petrology, v. 27, p.
745-750.
Lucas, S.G., and Heckert, A.B., 2001, Theropod dinosaurs and the Early Jurassic age of the
Moenave Formation, Arizona-Utah, USA: Neves Jahrbuch fur Geologic and Paläontologie
Mh., Stuttgart, Germany, v. 7, p. 435-448.
Lucas, S.G., Tanner, L.H., Heckert, A.B., and Hunt, A.P., 2005, Tetrapod biostratigraphy across
the Triassic-Jurassic boundary on the southern Colorado Plateau, USA, in Tracking dinosaur
origins, the Triassic/Jurassic terrestrial transition, abstracts volume, a conference held at
Dixie State College, St. George, Utah, March 14-16, 2005, p. 16.
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to the Colorado Plateau, in Caputo, M.V., Peterson, J.A., and Franczyk, K.J., editors,
Mesozoic systems of the Rocky Mountain region, USA: Denver, Colorado, Rocky Mountain
Section of the Society for Sedimentary Geology, p. 181-216.
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in the southern part of the Western Interior Basin, in Caputo, M.V., Peterson, J.A., and
WEST
EAST
Hornet Point
Elevation (feet)
U p p e r
9000
Jcx
Kcmc
La Verkin
Creek
Jccu
7000
Jcp
Jcp
Jccu
Jts + Jccl
Kcmc
Bear Trap
Canyon
fault
8000
K o l o b
P l a t e a u
Ksu
Kst
Kd
Kcmc
Jcp
Qmsy
Jcw
Jcx
Kcmc or Kd
A'
9000
Kst
Kcmc
Jts + Jccl
Jcx
Franczyk, K.J., editors, Mesozoic systems of the Rocky Mountain region, USA: Denver,
Colorado, Rocky Mountain Section of the Society for Sedimentary Geology, p. 233-272.
Sable, E.G., 1995, Geologic map of the Hildale quadrangle, Washington and Kane Counties,
Utah and Mohave County, Arizona: Utah Geological Survey Map 167, 14 p., 2 plates,
scale 1:24,000.
Sable, E.G., and Doelling, H.H., 1990, Geologic map of the Elephant Butte quadrangle, Kane
County, Utah and Mohave County, Arizona: Utah Geological and Mineral Survey Map
126, 10 p., 2 plates, scale 1:24,000.
—1993, Geologic map of The Barracks quadrangle, Kane County, Utah: Utah Geological
Survey Map 147, 11 p., 2 plates, scale 1:24,000.
Sable, E.G., and Hereford, Richard, 2004, Geologic map of the Kanab 30'x60' quadrangle,
Utah and Arizona: U.S. Geological Survey Geologic Investigations Series Map I-2655,
1 plate, scale 1:100,000.
Sable, E.G., Biek, R.F., and Willis, G.C., in preparation, Geologic map of the Smith Mesa
quadrangle, Washington County, Utah: Utah Geological Survey Map, 2 plates, scale
1:24,000.
Sansom, P.J., 1992, Sedimentology of the Navajo Sandstone, southern Utah, USA: Oxford,
England, Wolfson College Department of Earth Sciences, Ph.D. dissertation, 291 p.
Steiner, M.B., 2005, Correlation of Triassic/Jurassic boundary strata of North America through
paleomagnetic characteristics, in Tracking dinosaur origins, the Triassic/Jurassic terrestrial
transition, abstracts volume, a conference held at Dixie State College, St. George, Utah,
March 14-16, 2005, p. 24.
Tibert, N.E., Leckie, R.M., Eaton, J.G., Kirkland, J.I., Colin, Jean-Paul, Leithold, E.L., and
McCormic, M.E., 2003, Recognition of relative sea-level change in Upper Cretaceous
coal-bearing strata – a paleoecological approach using agglutinated foraminifera and
ostracods to detect key stratigraphic surfaces, in Olsen, H.C., and Leckie, R.M., editors,
Micropaleontologic proxies for sea-level change and stratigraphic discontinuities: Society
for Sedimentary Geology Special Publication no. 75, p. 263-299.
Tschudy, R.H., Tschudy, B.D., and Craig, L.C., 1984, Palynological evaluation of Cedar
Mountain and Burro Canyon Formations, Colorado Plateau: U.S. Geological Survey
Professional Paper 1281, 24 p., 9 plates.
Tuesink, M.F., 1989, Depositional analysis of an eolian-fluvial environment – the intertonguing
of the Kayenta Formation and Navajo Sandstone (Jurassic) in southwestern Utah: Flagstaff,
Northern Arizona University, M.S. thesis, 189 p.
Willis, G.C., and Hylland, M.D., 2002, Interim geologic map of The Guardian Angels
quadrangle, Washington County, Utah: Utah Geological Survey Open-File Report 395, 27
p., 1 plate, scale 1:24,000.
Willis, G.C., Doelling, H.H., Solomon, B.J., and Sable, E.G., 2002, Interim geologic map of
the Springdale West quadrangle, Washington County, Utah: Utah Geological Survey OpenFile Report 394, 19 p., 1 plate, scale 1:24,000.
Elevation (feet)
Qbhp
Kolob
Creek
Qmsy
Jccu
8000
Jcw
7000
Jts + Jccl
6000
6000
Jn
Jn
5000
5000
Jku
4000
Jks
Jku
3000
TRc
JTRm
TRc
4000
JTRm
Jks
TRm
1.02 ± 0.03 Ma (Qblp)
1.08 ± 0.02 Ma (Qblp)
1.44 ± 0.04 Ma (Qblc)
Large quartz monzonite boulders
Admentopsis n. sp.
Kayenta Formation
TERTIARY
A
Hornet Point flow and cinder cone
unconformity (J-1)
unconformity
Ta
0.22 to 0.31 Ma (Qbg)
0.22 ± 0.03 to
0.31 ± 0.02 Ma
MAP SYMBOLS
Temple Cap Formation
Jtw
Qbg
Jcp
unconformity (J-2)
Grapevine Wash lava flows (middle Pleistocene) – Medium-gray,
weathering to dark-brownish-gray to dark-brownish-black, fine-grained
olivine basaltic trachyandesite lava flows; erupted from a number of
vents on the Lower Kolob Plateau, including the Firepit Knoll and
Spendlove Knoll cinder cones; five 40Ar/39Ar plateau ages on these
flows range from 0.22 ± 0.03 Ma to 0.31 ± 0.02 Ma (Willis and Hylland,
2002); only distal end of one flow is preserved at the south end of Hop
Valley, in the southwest corner of the quadrangle, where it is about 20
feet (6 m) thick.
0-20 (0-6)
Jcw
Winsor Member (Middle Jurassic) – Light-reddish-brown, very fine
to medium-grained sandstone and siltstone; poorly cemented and
weathers to densely vegetated slopes; upper contact is the basal
Cretaceous unconformity; near Birch Spring, Winsor strata are
overlain by Cedar Mountain conglomerate, but in the northwest
corner of the quadrangle, the conglomerate is missing and the Winsor
Member is overlain by Dakota strata; deposited on a broad, sandy
mudflat (Imlay, 1980; Blakey and others, 1983); thickens westward
from about 240 to 320 feet (73-98 m) thick.
Major- and trace-element geochemistry and 40Ar/39Ar raw data is available
on the Utah Geological Survey Web site (http://geology.utah.gov/online/
analytical_data.htm); rock names are after LeBas and others (1986).
Qbg
K unconformity
Co-op Creek Limestone Member (Middle Jurassic) – Thin- to
medium-bedded, light-gray micritic limestone and calcareous shale;
locally contains Isocrinus sp. columnals, pelecypods, and gastropods;
deposited in a shallow-marine environment (Imlay, 1980; Blakey
and others, 1983).
Spring deposits
Grapevine Wash flows
Qbhpc
0.74 ± 0.05 Ma
Qbhp
Lower
unconformity (K)
Alluvial and colluvial deposits (Holocene to upper Pleistocene) – Poorly
to moderately sorted, generally poorly stratified, clay- to boulder-size,
locally derived sediments deposited principally in swales, small
drainages, and along the upper reaches of larger streams by fluvial,
slope-wash, and creep processes; gradational with both alluvial and
colluvial deposits; Qac deposits form active depositional surfaces and
are generally less than 20 feet (6 m) thick; Qaco deposits are deeply
incised and of similar thickness.
0-150
(0-40)
Ksu
Conglomerate member (Cretaceous, Cenomanian to Albian) – Thickto very thick bedded, yellowish-brown, channel-form conglomerate,
pebbly sandstone, and pebbly gritstone; clasts are subrounded to
rounded, pebble- to small-cobble-size quartzite, chert, limestone,
and rare, reworked petrified wood; locally stained reddish brown to
dark yellowish brown; forms two small exposures southwest of Birch
Spring and southeast of Little Creek Peak; deposited in river-channel
environment on broad, coastal plain (Tschudy and others, 1984;
Kirkland and others, 1997); Biek and Hylland (2007) reported a
single-crystal 40Ar/39Ar age of 97.9 ± 0.5 Ma on sanidine from a
volcanic ash in Cedar Mountain mudstone immediately above this
conglomerate bed in the Straight Canyon quadrangle to the east;
pollen analyses indicate an Albian or older age for these beds (Doelling
and Davis, 1989; Hylland, 2000); upper contact not exposed, but
regionally, east of the Hurricane fault, is unconformably overlain by
the Dakota Formation (see, for example, Kirkland and others, 1997);
previously mapped as the lower part of the Dakota Formation, but
the lithology, age, and stratigraphic position of these beds suggest
correlation to the Cedar Mountain Formation; 0 to 35 feet (0-11 m)
thick.
Carmel Formation
?
Qblc 1.44 ± 0.04 Ma
Dakota Formation (Upper Cretaceous, Cenomanian) – Interbedded,
slope- and ledge-forming sandstone, siltstone, mudstone, claystone,
carbonaceous shale, coal, and marl; sandstone is yellowish brown or
locally white, thin to very thick bedded, fine to medium grained;
includes two prominent cliff-forming sandstone beds, each several
tens of feet thick, in the upper part of the formation; mudstone and
claystone are gray to yellowish brown and commonly smectitic; oyster
coquina beds, clams, and gastropods, including large Craginia sp., are
common, especially in the upper part of the section; uppermost marl
beds above the uppermost sandstone cliff contain distinctive gastropods
with beaded edge Admetopsis n. sp. indicative of a latest Cenomanian
brackish environment (Eaton and others, 2001) (samples KRF in
sections 14 and 23, T. 38 S., R. 11 W.); Dakota strata are typically
poorly exposed and involved in large landslides; includes the overlying
Tropic Shale, which is restricted to the east part of the quadrangle
where it is silty and sandy and no more than a few feet thick (see, for
example, Eaton and others, 2001); upper contact placed at the top of
a slope-forming, coaly and marly mudstone sequence and at the base
of the typically cliff-forming sandstone of the Tibbet Canyon Member
of the Straight Cliffs Formation; deposited in a variety of flood-plain,
estuarine, lagoonal, and swamp environments (Gustason, 1989; Laurin
and Sageman, 2001; Tibert and others, 2003); invertebrate and palynomorph fossil assemblages indicate shallow-marine, brackish, and freshwater deposits of Cenomanian age (Nichols, 1995); probably about
850 feet (260 m) thick.
JURASSIC
Qrlc
Qblpc Qbkpc
Dakota Formation, Cedar Mountain Formation, and Winsor Member
of the Carmel Formation, undivided (Upper Cretaceous to Middle
Jurassic) – Mapped in the vicinity of Little Creek Peak, where access
to private land was denied; the Dakota Formation is present over most
of this area, Cedar Mountain strata may be present, and Winsor strata
are likely present at the lowest elevations.
Talus deposits (Holocene to upper Pleistocene) – Very poorly sorted,
angular boulders and finer-grained interstitial sediment deposited
principally by rock fall on and at the base of steep slopes; typically
grades downslope into colluvial deposits, and may include colluvial
deposits where impractical to differentiate the two; generally less than
30 feet (9 m) thick.
Q
Straight Cliffs
Formation
Cedar Mountain Formation
Kcmc
?
Qmso
(Kd)
unconformity
Landslide deposits (historical to middle[?] Pleistocene) – Very poorly
sorted, clay- to boulder-size, locally derived material deposited by
rotational and translational movement; characterized by hummocky
topography, numerous internal scarps, and chaotic bedding attitudes;
basal slip surfaces most commonly form in the lower unit of the Coop Creek Limestone Member of the Carmel Formation, the Dakota
Formation, and the upper unit of the Straight Cliffs Formation, and
the slides themselves incorporate these and overlying map units; the
Dakota Formation especially forms very large, complex mass movements; Qmsh denotes slides with historical movement; younger landslides (Qmsy) may have historical movement, but typically are characterized by slightly more subdued landslide features indicative of
early Holocene to late Pleistocene age; older landslides (Qmso) are
deeply incised and their main scarps and hummocky topography have
been extensively modified by erosion, suggestive of late to possibly
middle(?) Pleistocene age, but they too may be locally active; Qmso(Kd)
denotes large, relatively coherent bedrock blocks of the Dakota
Formation as much as about 150 feet (45 m) thick that slumped
downslope under the influence of gravity and which are late to possibly
middle(?) Pleistocene in age.
Surficial deposits
Member
LITHOLOGY
Lower
Mass-movement deposits
?
Upper
Lacustrine and basin-fill deposits (Holocene) – Well-stratified sand,
silt, and minor peat deposited in the Hop Valley basin in the southwest
corner of the quadrangle; grades into colluvial, alluvial, and alluvialfan deposits at basin margins and in upper part of deposits; forms
planar surfaces that slope downstream, which are incised about 40 feet
(12 m) at the south end of Hop Valley; a radiocarbon age of 2640 ±
60 14C yr B.P. establishes a minimum age for the formation of Hop
Valley Lake (Biek and others, 2003; Biek, 2007), and Eardley (1966)
obtained a radiocarbon age of 670 ± 200 14C yr B.P. from the upper
part of the deposits; deposits in Hop Valley are probably about 250
feet (75 m) thick (Biek, 2007), but are probably less than 60 feet (18
m) thick in this quadrangle; also mapped at Potamogeton (Chasm)
Lake, a permanent pond about 2 miles (3 km) west of Kolob Reservoir
that formed behind a rockfall of Navajo Sandstone; “Potamogeton” is
Latin for pondweed, which sometimes covers the pond’s surface. 14C
analytical data is available on the Utah Geological Survey Web site
(http://geology.utah.gov/online/analytical_data.htm).
?
?
Qmso
Middle
Qla
Tibbet Canyon Member (Upper Cretaceous, Turonian) – Grayishorange to yellowish-brown, generally medium- to thick-bedded,
planar-bedded, fine- to medium-grained quartzose sandstone and
lesser interbedded, grayish-orange to gray mudstone and siltstone;
locally contains pelecypods, gastropods, and thin to thick beds of
oyster coquina; typically forms cliffs, but in this quadrangle more
commonly weathers to steep, vegetated slopes; upper contact corresponds to a break in slope and is placed at the top of a coquinoid
oyster bed that caps the member; deposited in shoreface, lagoonal,
estuarine, and flood-plain environments of a coastal plain (Laurin
and Sageman, 2001; Tibert and others, 2003); thickens eastward
across quadrangle from about 240 to 450 feet (75-135 m) thick.
?
THICKNESS
Feet
(Meters)
Qer
Lower and Middle
Lacustrine and basin-fill deposits
Qst
C R E T A C E O U S
Kd
Qmt
Qmsy
Lower
Qc
Colluvial deposits (Holocene to upper Pleistocene) – Poorly sorted,
angular, clay- to boulder-size, locally derived sediment deposited
principally by slope wash and soil creep; gradational with talus deposits
and mixed alluvial and colluvial deposits; locally includes large areas
of talus where slope angles increase such that colluvium and talus form
a thin mantle that grades from one deposit to another; may include
undifferentiated landslide deposits; generally less than 20 feet (6 m)
thick.
Qc
Qae
SYMBOL
FORMATION
J U R A S S I C
KJu
Colluvial deposits
Qac
T R I A S S I C
Artificial-fill deposits (historical) – Engineered fill used to create the
Kolob Reservoir and Blue Springs Reservoir dams; unmapped fill is
locally present in developed areas; as much as 60 feet (18 m) thick.
Qmsh
Qaly
middle
and
lower
Upper
Qf
Qaf1
cross section only
Artificial-fill deposits
Qla
lower
Kst
Qf
Qas
Qaco
Pleistocene
Alluvial-fan deposits (Holocene) – Poorly to moderately sorted, nonstratified, boulder- to clay-size sediment deposited as small alluvial
fans along major drainages; form active depositional surfaces, although
locally the master stream is deeply entrenched; typically overlies
alluvial channel deposits at the toe of the fans, and locally includes
minor slope wash and talus along the upslope margins of the fans;
many small fans, because they are too small to depict at this scale and
because they are typically poorly developed, are lumped with mixed
alluvial and colluvial deposits; generally 0 to 30 feet (0-9 m) thick.
historical
prehistoric
Upper
Alluvial sand deposits (upper Holocene) – Well-sorted, fine- to mediumgrained sand on the floor of Hop Valley, in the southwest corner of the
quadrangle, where the Hop Valley stream has reworked the upper few
feet of sandy basin-fill deposits.
Upper unit (Upper Cretaceous, Santonian[?] to Turonian) – Slopeforming, grayish-orange to yellowish-brown, thin- to thick-bedded,
fine-grained subarkosic sandstone and gray mudstone and shale;
contains a few thin coal beds, common carbonaceous shale, and
several thin coquina beds; forms broad, rounded hills typically
mantled with unmapped colluvium; believed to be equivalent to the
Smoky Hollow Member and possibly John Henry Member of the
Straight Cliffs Formation of the Kaiparowits Plateau (see, for example,
Eaton and others, 2001); deposited in fluvial, flood-plain, and lagoonal
environments of a coastal plain (Eaton and others, 2001); incomplete
thickness as much as 320 feet (100 m) in the quadrangle, but upper
part not preserved.
Q U A T E R N A R Y
Ksu
upper
Straight Cliffs Formation
TERTIARY
Younger stream deposits (Holocene) – Stratified, moderately to wellsorted sand, silt, clay, and pebble to boulder gravel in river channels
and flood plains; locally includes small alluvial-fan and colluvial
deposits, and minor terraces as much as 20 feet (6 m) above current
stream level; equivalent to stream deposits (Qal1) and stream-terrace
deposits (Qat2) in the adjacent Kolob Arch quadrangle, but undivided
here due to uncertain correlation between upper and lower reaches of
drainages; generally 0 to 30 feet (0-9 m) thick.
Holocene
CRETACEOUS
CRETACEOUS
Qaf1
Alluvial deposits
J U R A S S I C
Qas
unconformity
TRIASSIC
Qaly
QUATERNARY
LITHOLOGIC COLUMN
SYSTEM
CORRELATION OF MAP UNITS
DESCRIPTION OF MAP UNITS
Thin surficial deposits not shown.
TRm
3000