Origin of the salt valleys in the Canyonlands section of the Colorado Plateau Evaporitedissolution c

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Origin of the salt valleys in the Canyonlands
section of the Colorado Plateau
Evaporite-dissolution collapse versus tectonic
subsidence

• F. Gutierrez

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Salt Anticline
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tectonic evolution of North America
explanation
North America maps are from Prof. Ron Blakey at
Northern Arizona U.
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Late Proterozoic (550 MA) Passive margins
followed rifting along Eastern, Southern, and
Western North America
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Late Cambrian (500 Ma) Complex transgressive
patterns of sedimentation onto NAM, long-lived
carbonate deposition begins in late
Cambrian West-facing Taconic arc (previously
rifted NAM fragments?) on eastern NAM
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Late Ordivician (450 MA) Continued patterns of
Late Cambrian sedimentation carbonates Continent
-wide Early Ordovician unconformity Taconic
terranes approach and collide to generate Taconic
orogeny
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Late Silurian (420 Ma) Baltica-Avalonia collides
with NAM Scandian and Acadian phases of
Calledonian orogeny Widespread carbonate
deposition across interior NAM Continued passive
margin on Western NAM as Antler arc terrane
approaches
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Early Devonian (400 Ma). Suturing of Baltica and
NAM form Calledonian-Acadian Mountains Major
orogeny in Arctic as arcs and fragments of
Siberia collide with Canada Antler arc approaches
and collides with Cordillera in the
west Continued widespread carbonate deposition
except in foreland basins
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Early Carboniferous (Mississippian, 345 Ma) NAM
and Gondwana approach Major collision with Africa
320 Ma
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Late Carboniferous (Pennsylvanian, 300
Ma). Appalachian orogeny Gondwana sutures with
Eastern US change in sedimentation from carbonate
to silisiclastic Gondwanan glacial cycles Early
phases of aeolian sedimentation in parts of
Western NAM General drying across Western Pangaea
thick salt deposits in Western Interior
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Late Permian (260 Ma) Widespread Aeolian and
fluvial redbed deposition across Western Interior
and North Sea region thick carbonate deposition
in basins complex lateral and vertical facies
changes continued cyclicity Major global marine
lowstand late in Permian extensive salts
deposited on craton from Nebraska to Texas and
across Northern Europe.
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Early Triassic (245 Ma). Rifting and basaltic
magmatism along East Coast signals early stages
of break-up of Western Pangaea Lowstand
continues
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Early Jurassic (195 Ma). Atlantic Ocean opens
from Maritime Canada into Gulf of Mexico
Yucatan rifts and drifts S as Gulf opens
Pangaean mountains including Appalachians mostly
worn down by erosion Widespread Aeolian
deposition across Western Interior formed
greatest aeolian deposits in rock record
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Late Jurassic (150 Ma). (Major Cordilleran arc
magmatism in Middle Jurassic) Major plate
reorganization in Late Jurassic -- change in
relative plate motion (to sinistral) of Farallon
Plate with respect to North America causes
Wrangellia to begin moving southward
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Early Cretaceous (140 Ma). Rapid spreading of
Atlantic Ocean
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Early Cretaceous (130 Ma). Great Valley fore arc
basin and Franciscan subduction complex built on
reorganized Cordilleran margin
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Early Cretaceous (115 Ma). Western Interior
seaway reestablished North Slope terrane rotated
CCW as Canadian basin opened
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Late Cretaceous (100 Ma). Caribbean sea begins
to open as South America pulls away from NAM
Silisiclastic sedimentation along N and W margins
of Gulf of Mexico Marine highstands cause
expanded Western Interior seaway Cordilleran
arc renewed with large plutonic events
(Penninsular, Sierra Nevada, Idaho Coast Range
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Late Cretaceous (85 Ma). Arctic Amerasian basin
fully opened Foreland basin deposits form
complex transgressive-regressive cycles on W side
of seaway Active plutonic activity in
Sierra-Idaho-Penninsular (100-85 Ma) followed by
strong decline and null in arc activity (80-40 Ma)
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Late Cretaceous (75 Ma).
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Cretaceous/Tertiary boundary (65
Ma). Extraterrestrial impact forms depression in
NW Yucatan at 65 Ma
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Middle Eocene (50 Ma). Uplift of Coast Range
plutonic complex generated deep-sea fan deposits
(Chugach flysch) onto ocean floor. Many terranes
approach their present latitude with respect to
North America by 50 40 Ma Olympic terrane
accreted 50 Ma California borderlans active
basins inboard fill with thick marine and
continental deposits
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Oligocene (25 Ma). Passive margin along Atlantic
and Gulf Coast Greenland rifts from NAM. S
Colorado Plateau high and dissected 25Ma Several
episodes of planation and exhumation of Rocky
Mountains Deposition of extensive wedges of
Rocky Mountain sediment into Gulf of Mexico
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Middle Miocene (15 Ma). Colorado Plateau high --
relative undissected until last 5 7 million
years. Complex erosion and exhumation continues
in Rocky Mountains. Basin and Range orogeny
early (30 15 Ma) extension along large
detachment faults late (10 0 Ma) normal
high-angle faulting extensive basaltic magmatism
in Basin and Range and on S, W, and E margins of
Colorado Plateau expansion of transform Pacific
margin throughout Neogene subduction continues
N and S of transform margin
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Pliocene (3 Ma). Opening of Gulf of California
/- 5 Ma allowed integration of Colorado River
system by complex stream capture and canyon
cutting and erosion of Colorado Plateau and Rocky
Mountains
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Late Quaternary glacial.
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Late Quaternary interglacial.
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Tectonic ModelDeveloped by Ge and Jackson 1998

• Salt Withdrawal

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Tectonic Model Setup
Ge and Jackson, 1998
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Faulting
Normal Faulting
Reverse Faulting
Ge and Jackson, 1998
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CZ Contractional Zones
EZ Extensional Zones
Ge and Jackson, 1998
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Extension
Ge and Jackson, 1998
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Salt Anticline
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Big Gypsum Valley

• http//130.166.124.2/co_panorama_atlas/page56/file
  s/page56-1001-full.html

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• http//earth.leeds.ac.uk/faults/normal/listric.htm

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Tectonic vs. Dissolution
Ge and Jackson, 1998