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AMETERS
2000
1500
1000
500
SEA LEVEL
500
1000
1500
2000
Trm Trl
Cle
Elu
m L
ake
Yak
ima
Riv
er
Big
Cre
ek
BlazedRidge
KesQ
Ked
KhbTbf
TnrWH
ITE
RIV
ER
FA
ULT
ZO
NE
TnrTnb
TnsTo
Lit
tle
Nac
hes
Riv
er
Tf
Cro
w C
reek
TeTfbTfTn Tn
Tta
TmKbg Easton
Ridge
TtTtTssp
Tss
Wes
t For
k T
eana
way
Riv
er
QQQG
reen
Riv
er
HuckleberryMountain
WH
ITE
RIV
ER
FA
ULT
ZO
NE
Whi
te R
iver
Che
nuis
Cre
ek
TfciTf
QTfcr
To
Tcr
Tfce
Tf Tfst
Tfst
To
To ToTeg Tf
TfTf
ToTo
TfrtTfrtTegTeg
Q
CougarMountain
Q Q
TfTfce
Cle
Elu
m R
iver
GoatMountain
Wap
tus
Riv
er
Coo
per
Riv
er
ST
RA
IGH
T C
RE
EK
FA
ULT
ZO
NE
RampartRidge
Coa
l Cre
ek
CascadeCrest
Han
sen
Cre
ek
Ced
ar R
iverGrass
Mountain
Whi
te R
iver
Sout
h P
rari
e C
reek
KJisTss
Q
TdrdTdv
TssTdgr
Tdv
TdgrTss
TdgrTss
TssKesKedKed
KesTnr
TstnTns
QTnbg
TnbgTnrTnbgTnmc
Tnmc TngTng TnmcTsgsTsgs
TegTf
To
Teg QToTf
TfrtTegTf
Tf
ToTfcr
TfTfcrTo
To
Tip
Tp
Teg To
Tfce Q
Gre
en R
iver
Gol
d C
reek
Tns
Q QQ
QQQQQ
Q
QQ Q
Q
BE
ND
IN
SE
CT
ION Box
RidgeA''
METERS2000
1500
1000
500
SEA LEVEL
500
1000
1500
2000
C'METERS2000
1500
1000
500
SEA LEVEL
500
1000
1500
2000
CMETERS
2000
1500
1000
500
SEA LEVEL
500
1000
1500
2000
500 meters=1640.4 feetUnconsolidated deposits, (Q) undifferentiated and exaggerated in thickness, small areas not shown
500 meters=1640.4 feetUnconsolidated deposits, (Q) undifferentiated and exaggerated in thickness, small areas not shown
500 meters=1640.4 feetUnconsolidated deposits, (Q) undifferentiated and exaggerated in thickness, small areas not shown
B'METERS2000
1500
1000
500
SEA LEVEL
500
1000
1500
2000
BMETERS
2000
1500
1000
500
SEA LEVEL
500
1000
1500
2000
A'
SE
CT
ION
B-B
'
20
20
20
40
30
30
m
Qa
Qb
Ql
Qmw
Qt
Qlh
Qu
Qag
Qvr
Qvi
Qvt
Qva
Qvu
Qpf
Qpfa
Qra
Qcc
Qcct
Tbd
Th
Tcp
TgnF
TgrF
Te
Tsgs
Tsgf
Tsgg
Tstn
Tsm
Tcr
Tip
Tit
Tiap
Tidp
Tf
Tfv
Tfb
Tfc
Tfci
Tfce
Tfrt
Tfst
Tfcr
Teg
Tdv
Tdgr
Tdrd
Tdb
Tdr
To
Tolk
Tv
Tdg
Tn
Tns
Tng
Tnb
Tnr
Tnbg
Tnmc
Tp
Tpr
Tpt
Tptm
Tmp
Trr
Tru
Trm
Trl
Tt
Tdg
Tss
Tsc
Tssp
Tsi
Tbf
Tbfb
Tta
Tm
TKwa
TKwv
TKwg
TKwu
TKev
TKem
pTqm
pTlm
pTla
pTlg
TKt
TKtu
Kt
Knp
Kes
Ked
Ktz
Khb
Kbg
KJim
KJid
KJia
KJis
LIST OF MAP UNITS(See pamphlet for complete map unit descriptions)
MASS WASTAGE AND ALLUVIAL DEPOSITS
Man-Modified land (Holocene)
Alluvium (Holocene and Pleistocene)
Bog deposits (Holocene and Pleistocene)
Landslide deposits (Holocene and Pleistocene)
Mass-wastage deposits (Holocene and Pleistocene)
Talus deposits (Holocene and Pleistocene)
Lahar deposits (Holocene and Pleistocene)
GLACIAL DRIFT AND RELATED DEPOSITS
Surficial deposits, undivided (Holocene and Pleistocene)
Alpine glacial deposits (Pleistocene)
Deposits of Vashon stade of Fraser glaciation of Armstrong and others (1965) of Cordilleran ice sheet (Pleistocene)ÑDivided into:
Recessional outwash deposits
Ice-contact deposits
Till
Advance outwash deposits
Vashon Drift, undivided
Glacial and nonglacial deposits of pre-Fraser glaciation age (Pleistocene)
Alpine glacial drift of pre-Fraser glaciation age (Pleistocene)
BEDROCK
Andesite of Mount Rainier (Pleistocene)
Basalt of Canyon Creek (Pleistocene)ÑLocally, includes:
Basaltic tuff and breccia
Basalt of Dalles Ridge (Pliocene)
Howson Andesite (Miocene)
Volcaniclastic rocks of Cooper Pass (Miocene)
Columbia River Basalt GroupÑDivided into:
Grande Ronde Basalt (Miocene)ÑDivided into:
Flows of normal magnetic polarity
Flows of reverse magnetic polarity
Ellensburg Formation (Miocene)
Rocks of Snoqualmie batholithÑDivided into:
Tonalite and granodiorite, southern phase (Miocene)
Fine-grained monzonite (Miocene)
Granodiorite and granite (Miocene)
Tonalite and granodiorite, northern phase (Miocene and Oligocene)
Mafic diorite and gabbro (Miocene and Oligocene)
Carbon River stock (Miocene)
Intrusive rocks (Miocene and Oligocene)ÑDivided into:
Pyroxene andesite porphyry
Tonalite
Altered porphyry
Dacite porphyry
Fifes Peak Formation (Miocene)ÑDivided into:
Volcaniclastic rocks
Andesite and basalt megabreccia
Crystal-lithic tuff
Rhyolite unit of Clear West PeakÑDivided into:
Intracaldera rhyolite
Extracaldera rhyolite tuff
Rhyodacite tuff
Sun Top unit
Chenuis Ridge unit
Volcanic rocks of Eagle Gorge (Miocene and Oligocene)
Volcanic rocks of Mount Daniel (Oligocene)ÑDivided into:
Andesite, dacite, and rhyolite volcanic rocks
Granophyre and rhyolite porphyry
Rhyodacite tuff
Breccia
Rhyolite
Ohanapecosh Formation (Oligocene)ÑLocally, includes:
Tuff member of Lake Keechelus
Volcanic rocks (Oligocene)
ROCKS WEST OF THE STRAIGHT CREEK FAULT
Diabase, gabbro, and basalt (Oligocene? and Eocene)
Green River-Cabin Creek Block
Naches Formation (early Oligocene? to middle Eocene)ÑDivided into:
Feldspathic sandstone and volcanic rocks (late and middle Eocene)
Rhyolite (late and middle Eocene)
Basalt (late and middle Eocene)
Guye Sedimentary Member (late and middle Eocene)
Mount Catherine Rhyolite Member (late and middle Eocene)
Glomeroporphyritic basalt (late and middle Eocene)
Puget GroupÑDivided into:
Renton Formation (late and middle Eocene)
Tukwila Formation (late and middle Eocene)
Tiger Mountain Formation (middle Eocene)
Volcanic rocks of Mount Persis (late? Eocene)
Raging River Formation (middle Eocene)
ROCKS EAST OF THE STRAIGHT CREEK FAULT
Teanaway River Block
Roslyn Formation (late and middle Eocene)ÑDivided into:
Upper member (late Eocene)
Middle member (late and middle Eocene)
Lower member (middle Eocene)
Teanaway Formation (middle Eocene)
Diabase, gabbro, and basalt (Eocene)
Swauk Formation (middle and early Eocene)ÑDivided into:
Sandstone
Conglomerate facies (middle and early Eocene)
Silver Pass Volcanic Member (early Eocene)
Ironstone (early Eocene)
Manastash River Block
Basalt of Frost Mountain (middle Eocene)—Locally divided into:
Basalt breccia and tuff
Taneum Formation (early Eocene)
Manastash Formation (early Eocene)
ROCKS SOUTHWEST OF DARRINGTON-DEVILS MOUNTAINFAULT ZONE
Rocks of the western mélange belt (middle Eocene and (or) Late Cretaceous)ÑDivided into:
Argillite and graywacke
Metavolcanic rocks
Metagabbro
Ultramafic rocks
Rocks of the eastern mélange belt (middle Eocene and (or) Late Cretaceous)ÑDivided into:
Chert, mafic metavolcanic rock, amphibolite, and marble
Marble
Quartz Mountain stock (pre-Tertiary)
Lookout Mountain Formation of Stout (1964) (pre-Tertiary)ÑDivided into:
Mica schist
Amphibolite and hornblende tonalite gneiss
Gabbro and metagabbro
ROCKS IN DARRINGTON-DEVILS MOUNTAIN FAULT ZONE
Tectonic complex of Stout (1964) (Tertiary and (or) Cretaceous)— Locallydivided into:
Ultramafic rocks
ROCKS NORTHEAST OF DARRINGTON-DEVILS MOUNTAIN
FAULT ZONE
Tonalite (Late Cretaceous)
Metavolcanic rocks of North Peak (Late Cretaceous)
Easton Metamorphic Suite (Early Cretaceous)ÑDivided into:
Shuksan Greenschist
Darrington Phyllite
Tectonic zone (Early Cretaceous)
Tonalite gneiss of Hicks Butte (Early Cretaceous)
Banded gneiss (Early Cretaceous)
Ingalls Tectonic Complex (Early Cretaceous or Late Jurassic)
Foliated and massive serpentinite and serpentinized meta-peridotite
Metabasalt, tuff, and breccia
Diabase and gabbro
Amphibolite
ContactÑDashed where inferred; dotted where concealed; queried where uncertain
High-angle FaultÑDashed where inferred; dotted where concealed. Bar and ball on
downthrown side. Arrows shown in cross section indicate direction of relative
movement
Major FoldsÑDotted where concealed. Arrowhead along axial trace shows
direction of plunge
Anticline
Syncline
Overturned Syncline
Strike and dip of bedding
Inclined
Inclined, top known
Overturned
Overturned, top known
Vertical
Vertical, top towards ball
Horizontal
Strike and dip of foliationÑIn igneous and metamorphic rocks
Inclined
Vertical
LineationÑShowing bearing and plunge. May be combined with other symbols
Zone of sheared rockÑSee description of sandstone unit of Swauk Formation (Tss)
Zone of foliated rockÑSee Description of foliated and massive serpentinite and
serpentinized metaperidotite (KJis) of Ingalls Tectonic Complex
Zone of silicified rhyolite
Crest of moraine
SpillwayÑArrow indicates direction of flow of drainage from recessional glacial
lakes. Number indicates present day altitude
Landslide arrowÑShows direction of movement of landslide
Location of dated sampleÑSee Table 1 in pamphlet
Teanway dike swarmÑArea underlain by dikes. Density of symbols indicate
estimated percent
mQa Qb
Ql Qmw
Qt Qlh
**Numbers in map-unit symbols represent specific recessional intervals 1-7 (1 being
the oldest) that are shown. No number indicates an indeterminate age in intervals 1-7.
Multiple numbers indicate an indeterminate age within the expressed range.
ROCKS WEST OF STRAIGHT CREEK FAULT
Green River-Cabin Creek Block
Tfv Tfc
TfciTfce
Tf
Tfcr
Tfb
TfrtTfst
Tn
Tnmc
Tnb
Tnbg
Tns
Tng
Tnb
Tnr
TnrTpr
Tpt
Tptm
TpTn
TbfbTbf
TKtu*
TKt*
TKwgTKwu
TKwv
TKwa
TKem
TKev
pTqm*
KtKnp
Kes Ked Ktz Khb Kbg
KJiaKJis
KJim
KJid
Tta
Tm
Tt
TsspTsc
Tss
Tsi
KJiaKJis
KJim
KJidKhb
Kes Ked
Knp
pTqm
TKwg
TKwa
TKev
TKem
pTlm pTla
Vashon
stade
Fraser
glaciation
Holocene
Pleistocene
QUATERNARY
Pleistocene
Miocene
QUATERNARY
Oligocene
TERTIARY
Pliocene
Early
Oligocene(?)
Middle
Eocene
Late Eocene
Early Eocene
Oligocene(?)
Eocene
TERTIARY
Middle
Eocene and
(or) Late
Cretaceous
Eoceneand (or)Cretaceous
Late
Cretaceous
Early
Cretaceous
EarlyCretaceousor LateJurassic
Late Jurassic
Pre-LateJurassic
EarlyJurassic
JURASSIC
CRETACEOUS
OR JURASSIC
ROCKS EAST OF STRAIGHT CREEK FAULT
TERTIARY AND
(OR) CRETACEOUS
CRETACEOUS
PERMAIN
TO
DEVONIAN
Teanaway River Block Manastash River Block
ROCKS SOUTHWEST OF
DARRINGTON-DEVILS MOUNTAIN
FAULT ZONE
ROCKS IN
DARRINGTON-DEVILS MOUNTAIN
FAULT ZONE
ROCKS NORTHEAST OFDARRINGTON-DEVILSMOUNTAIN FAULT ZONE
BEDROCK
Tdgr
Tdv
Tdrd
Tdb
153
160
Middle
Jurassic
95
84
52
47
40
37
36
28
25
19
21
20
12
6
52.41.6
0.70
0.55
0.01
MASS WASTAGE AND ALLUVIAL DEPOSITS GLACIAL DRIFT AND RELATED DEPOSITS
Unconformity
Uncomformity
Qag
Qvr** Qvi** Qvt Qva Qvu
Qpf Qpfa
Qu
QraQccQcct
Tbd
Th
Tcr Tsgs Tsgf
Tsgg
Teg
Tstn Tsm
TvTo
Tcp
TeTgn2
Tgr2
Tip Tit
Tidp
TiapTdr
Trl
Trm
Tru
Tdg
Trr
Tmp
Tdg
pTlg*
pTla*pTlm*
Tolk
CORRELATION OF MAP UNITS[*See Description of Map Units in pamphlet for specific unit age assignment]
Note: For m�lange and metamorphic units, position of boxes with solid boun-
daries indicates age of assemblage or metamorphism, respectively; position
of boxes with dashed boundaries indicates age of protolith
Approximate age (Ma)(From time scale of Cowieand Bassett, 1989 and
Berggren and others, 1985)
ST
RA
IGH
TC
RE
EK
FA
ULT
DDMFZ
WHITE
RIVER
FAULT
ZONE
MANASTASHRIVER BLOCK
Figure 2. Generalized geologic map of Snoqualmie Pass quadrangle, Washington. DDMFZ, Darrington-Devils Mountain Fault Zone.
0
0 5 10 m
5 10 km
GREEN RIVER -- CABIN CREEK BLOCK
KeechelusLake
KachessLake
SnoqualmiePass
Howard HansenReservoir
GraniteMtn
NorthBend
Chester MorseLake
122°47°30'
121°
Cle ElumLake
TEANAWAY RIVERBLOCK
Roslyn
Enumclaw
SNOQUALMIEBATHOLITH
Clear WestPeak
HicksButte
CARBON RIVERSTOCK
Kachess Ridge
47°00'
Huckelberry Mountain
NachesPass
Unconsolidated deposits
(includes some deposits of
the Cascade Arc)
Marine sandstone and shale
(Raging River Formation)
Basalt and andesite flows and
breccia (Teanaway Formation, and
basalt of Frost Mtn)
Terrane units
ROCKS SOUTHWEST
OF DARRINGTON-
DEVILS MTN
FAULT ZONE
ROCKS NORTHEAST
OF DARRINGTON-
DEVILS MTN
FAULT ZONE
ROCKS IN
DARRINGTON-DEVILS
MTN FAULT ZONE
(DDMFZ)
Rocks of western and eastern
m�lange belts (includes
Lookout Mtn Formation of
Stout, 1964, Quartz Mtn stock)
Serpentinite and argillite
matrix tectonic breccia
(tectonic complex of
Stout, 1964)
Easton Metamorphic Suite1
(includes tonalite gneiss of
Hicks Butte, tectonic zone)
Ultramafic rocks1
(Ingalls Tectonic Complex)
Metamorphic rocks of
North Peak1
Basalt, andesite,
and minor dacite
Rocks of Cascade Arc
Columbia River
Basalt Group
Andesite basalt, rhyolite, and
dacite (Fifes Peak Formation)
Tonalite to granite
(includes rocks of
Snoqualmie batholith,
Carbon River stock)
Andesite, basalt, and dacite (includes
Ohanapecosh Formation,
volcanic rocks of Mt Daniel)
ROCKS WEST OF
STRAIGHT CREEK FAULT
Green River-Cabin Creek Block
Interbedded fluviatile sandstone
and volcanic rocks (includes
Pugit Group, Naches Formation)
Fluviatile sandstone, shale, and
coal (Roslyn Formation)
ROCKS EAST OF
STRAIGHT CREEK FAULT
Teanaway and Manastash River Blocks
Fluviatile sandstone and dacitic volcanicrocks (Includes Swauk, Manastash,
and Taneum Formations)
Unconformity
QUATERNARY
Pliocene
and
Miocene
Miocene
Oligocene
Oligocene(?)
Eocene
TERTIA
RY
MiddleEocene
and(or)Late
Cretaceous
Early
Cretaceous
Early
Cretaceousor
LateJurassic
TERTIA
RY
AND(O
R)
CRETACEOUS
CRETA-
CEOUS
CRETA-
CEOUSOR
JURASSIC
PERMIA
NTO
DEVONIA
N
ContactÑDotted where concealed
FaultÑDotted where concealed
Structural block boundary and fault
SynclineÑDotted where concealed.
Arrow indicates plunge
AnticlineÑDotted where concealed.
Arrow indicates plunge
EXPLANATION
1Unit shown by protolithic age
Area of Figure 2
OLYMPIC
WALLOWA
LINEAMENT
Seattle
CANADA
UNITED STATES
British Columbia
Washington
DARRINGTON-DEVILSM
TN
FA
UL
TZ
ON
E
WESTERNAND
EASTERN
MÉ
LAN
GE
BE
LT
Chelan
Wenatchee
WHITERIVER
FAULTSNOQUALMIE
PASS WENATCHEE
CHELAN
SKYKOMISHRIVER
HELENA-HAYSTACKMÉLANGE
SaukR
ManastashRidgearea
Mt Baker
Mt Shuksan
GlacierPeak
KyesPeak
HaystackMtn
Mt Daniel
Mt Stuart
Mt Rainier
Rimrock Lake
inlier
NORTHWESTCASCADESYSTEM
Area of Figure 1
WASHINGTON
Cascade
Cre
st
OLYMPIC
MOUNTAINS
SnoqualmiePass
SanJuan
Islands
Skagit
River
NORTHWEST
CASCADE
SYSTEM
JUAN DE FUCASTRAIT OF
PU
GE
TLO
WLA
ND
TongaFm
I-90
Bellingham
MountMisch
Darrington
Yakima
Rive r
FA
ULT
EN
TIA
T
0 60 KILOMETERS
60 MILES0
TERTIARY SEDIMENTARYAND
VOLCANICROCKS
CO
LUM
BIA
RIV
ER
IslandVancouver
NORTH
CASCADECRYSTALLNE
CORE
ST
RA
IGH
TC
RE
EK
FA
ULT
Figure 1. Regional overview of geologic setting for Snoqualmie Pass quadrangle, Washington. Arc plutons are
not shown. Wenatchee 1¡ by 2¡ quadrangle is composed of the Skykomish River, Chelan, Snoqualmie Pass, and
Wenatchee 1:000,000-scale quadrangles (shown in magenta).
123° 122° 121° 120°
49°
48°
47°
ALPINE LAKESWILDERNESSAREA
ALPINE LAKES
WILDERNESSAREA
NORSE PEAK
WILDERNESSAREA
CLEARWATER
WILDERNESS
AREA
A
B'
A"
B C
C'
A'
Ql
Qag
Tf
Teg
To
Qu
QagTeg
Tidp Qag
Ql
TipTo
Qa
Tiap
Tip
Tip
Teg
Ql
Ql
Tpt
KJis
KJis
Qvt
Qa
Trr
Tss
QvtQvt
Tss
QaTstn
TKwa QagTstn
QaQvt
Qag
Tdrd
Qa
Trr
Qa
Tdgr
Qvt
Tnbg Kt
TvTKwa
Qa
Tdr
Qvt
Qva Qa
Tv
Ql
QaKed
Tns
Qa
KJim
Qa
QaQvrQa
Qa Tstn
Ked
To
TKwaTKwgQvt
TnrQt
QaQvr
Tns
QvtTpt
Qvt
Qva
Qva
Qag
Tsm
QvtTsgs
Qvr
QagQa
Tng Tns
Qa
Qa
Qvt
Qvr
Tp
Qag
Tng
Qvi
Qa
Tp
Teg
QaTitTp
Tp
Qvt
Qvt
Qu
Tt
Tp
Qvt
TsgsQa
TpQa
Qvr
QuQag
To
TsmTp
Tn
Qb
Qa
QuTegQaQag
Qa Qb
Qmw
Tt
Qa
Qa
TnTidpQagTn
QaTnr
Qa
Tns
Tt
QbTp
Qa
Qag
Teg
Teg
Tf
Teg
TpQa
Tnr Qa
TfQag
Tfrt Qa
Tnr
Tru
Tnr
Ql
QvtTo
To
Tp
Qvu
Qmw
Qlh
m
QlQa
Qa
Qa
Tnr KesTf
Qag
TnQlTeg
Qvi
Tf
Qa
Qa
Tn
QviQag
Tit
Tit
Qlh
Tf Tf
Tns
Tf
Qa
Ked
Tm
QvrQa
Tf
Qa
To
Tidp
Ql
Qlh
Qlh Qvt
Tit
Tf
Tf Tfst
Qa Qlh
QaTiapQlh
Qvu
Qlh
Tm
To
Ked
Qa
Tf
Tfst
Qlh
Qvu
Tf
Tnr
Tta
Qa
QlTnr
Tm
Tiap
Qcc
Ql
Qa
Tf
Qlh
Ql
Tfce
Qvu TfstTo TiapTo
To
Tf
QaTit
Tbd
Tip
TmQcct
Tip
Tnr
QlTfv
Tnb
pTla
pTlg
pTlg
Tfst
QlQag
QlQag
Qa
Tf
Tip
TnsQl
Qlh
TfTip
QagQl
TfTfTip
Tfst
Ql
QlQpfa
TnsQl
Qag
QlQa
Qpfa
Qt
TgnF
TnsTgnF
Qra
Ql
Tfst
Ql
Tf
Tfci
TfbQa
To
Qa
Tf
Ql Tn
Tf
Qa
QaTnbTfcr Tit
TptQvt
Tp
Tpt
Tpr
Tpt
Tp
Qvr
Ql
Tmp
Tpr
Tpt
Tpt
Tp
Tptm
TKwg
TKwa
Qa
TKwg
TKwg
Tsm
Tsgs
TKwa
Tv
Qmw
Tsm
Tv
Qag
Tsgg
Qa
Tng
Tsgg
TKev
Tnmc
TKem
Tv
Tstn
Qag
Ql
Tn
Qag
Tv
Qt
Qt
Qa
Tstn
Ql
Ked
Tnr
Tcp
Qag
Tdrd
Ql
Tdv
Tit
Qa
Qag
Qa
Qa
Qa
Ql
Qag
Tss
Qt
Tdgr
Qa
Tss
Ked
Kes
Tns
Qa
Qt
To
Tolk
Tnbg
Tng
Tnmc
Qag
To
QaTsm
Tsgs
Ql
Qa
TKwg
To Tit
Tip
Qvt
Qpf
Qvt
Tp
Tdg
Tp
Tdg
Ql
Tp
To
Qu
Qag
Teg
Tp
Qag
Qmw
Ql Ql
Tidp
QagQag
Tolk
Tssp
Tssp
To
Tf
Qa
Qvr
Ql
Qag Tfrt
Teg
Qpfa
Qag Tp
To
Tfcr
Tcr
Qt
Tfci
Qt
Tfci
Qag
Tit
Qpfa
Qmw
Tfst
Qlh
To
Ql
Qt
Tip
Tfv
Ql
Ql
Tnr
Tnb
pTlm
TKt
Tbfb
Ql
Tbfb
Tbf
Tta
Tdg
pTla
Khb
Qag
Qa
Qa
Qag
Tnb
Tn
Tbf
Tit
Ql
Ql
Qag
Tdg
Qa
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To
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Teg
Teg
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Qa
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Tp
To
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Tiap
Tns
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Trm
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Tpt
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Tit
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Qa
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To
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TgnFTns
Ked
Qag
TKtTdg
Tnb
TKtu
TKtu
Tdg
QlQa
QaTf
Qa
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Qpfa
Tp
To
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To Tiap
TitTn
Tdg
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Tv
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Tip
Tip
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Khs
TitKnp
Ked
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QaTeg
TKwu
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Tnmc
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Tit
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TstnTstnTKwv
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Tit
Tsc
Qt
Tp
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TssKes
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Trm
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To
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To
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3-4
3
4
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Qvi1
Qvr
Qvr
Qvr4
Qvr2
6
Qvi5
Qvr3-6
Qvr3-6
Qvi3
Qvr1
Qvr1
Qvr1
Qvi3
Qvr1
Qvi1-2
Qvr2-3
Qvr5
Qvr5
Qvi3-4
Qvr1
Qvr1
Qvr2
Qvr1-2
Qvr1-2
Qvi 1
Qvi 1
Qvr1
Qvr1
Qvr1
Qvr6
Qvi5
7
Qvi1-2
Qvi1-2
Qvr
Qvr2
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2Qvi3-4
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Qvr1
Qvr1
Qvr1
Qvr1
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Qvr3
Qvr
Qvr
U.S. DEPARTMENT OF THE INTERIOR
U.S. GEOLOGICAL SURVEY
Geology mapped by V.A. Frizzell, Jr., R.W. Tabor, and R.B. Waitt, 1975-82; S. Allshouse and E.A. Rodriquez, 1975; J.F. Coburn and R. Tal, 1976; W. Gaum, M. Goddard, and K.L. Marcus, 1977; E.L. Mathieson and N.B. Shew, 1978; D.B. Booth, 1978-82; S.F. Connally, S.L. Sandberg, F. Beall, F.C. Moser, and S. Cook, 1981; C. Eddy, K.M. Ort, and T. Schirmer, 1982
Digital database by R.W. Tabor
Edited by Dale Russell, Julia Thomas, and Jan Zigler; digital cartography by Kathryn Nimz with assistance from Taryn A. Lindquist, Sara Boore, Susan Mayfield, and Kevin Ghequiere
Manuscript approved for publication January 23, 1995
Base from U.S. Geological Survey, 1975
Transverse Mercator projection
SCALE 1:100 000
1 10 4
5000 100000 15000 20000 25000 FEET
1 0 3 5 7 8 10 KILOMETERS
5 MILES
1 2 4 6 9
2 3
5000
CONTOUR INTERVAL 50 METERSNATIONAL GEODETIC VERTICAL DATUM OF 1929
WASHINGTON
AREA OF QUADRANGLE
GEOLOGIC MAP OF THE SNOQUALMIE PASS 30×60 MINUTE QUADRANGLE, WASHINGTONBy
R.W. Tabor, V.A. Frizzell, Jr., D.B. Booth, and R.B. Waitt2000
GEOLOGIC INVESTIGATIONS SERIES
MAP IÐ2538
Pamphlet accompanies map
APPROXIMATE MEANDECLINATION, 2000
MA
GN
ET
IC
NO
RT
H
18 / °12
TR
UE
N
OR
TH
47°00'
47°30'122°00'
45' 121°00'47°30'
15'
47°00'121°00'15'30'122°00'
15'
30' 15'
45'
WASHINGTON
For sale by U.S. Geological Survey, Information Services, Box 25286,Federal Center, Denver, CO 80225, or call 1–888–ASK–USGS
Available on World Wide Web at http://geopubs.wr.usgs.gov/i-map/i2538Printed on recycled paper
INTERIOR—GEOLOGICAL SURVEY, RESTON, VA—2000
80-85% 5-10%
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