Nooksack River

Skagit River

Stillaguamish River

Snohomish River

Skykomish River

Snoqualmie River

Cedar River

Green River

Puyallup River

Puyallup R.

White R.

Carbon R.

Nisqually River

Skokomish River

Quilcene River

Dosewallips River

Duckabush River

Chehallis River

Satsop

River

Deschutes River

Black River

Quinalt R.

Elwah

River

PUGET SOUND

STRAIT OF JUAN DE FUCA

GEORGIA STRAIT

Catfish Lake

Bainbridge 

Island

 

Frigid 

Creek

Cottage Lake

Vasa Park

Kendall

Sunset Beach

Saddle MtnPrice Lake

Lake CreekBoundary Creek 

Smuggler

Canyon 

River

Rocky Point Whitman Bench

Waterman Pt

Lake Creek

BELLINGHAM

EVERETT

SEATTLE

TACOMA

OLYMPIA

VICTORIA

CANADA

U.S.A.

20 Miles 20 Km 1:600,000

47°

47°30’

46°50’

48°

48°30’

123°30’ 123° 122°30’ 122° 121°30’

49°

MAP 1: PALEOSEISMIC STUDIES IN PUGET LOWLAND

OLYM

PIC

M

O

UNTA

N

I

S

CASCA

D

E

RAN

GE

Mount Rainier

Mount Baker

VANCOUVER 

ISLAND

Area of Inset Map 3

2006 USGS North Puget Sound survey

2000-2007 Puget Sound Lidar Consortium 

2002-2003 NASA/USGS survey

2006 Snohomish County survey

2003 King County 

PUGET SOUND LIDAR DATA SOURCES

Paleoseismic coastal study site:

Bucknam, 1999 

Sherrod 1998, 2001:

 Uplifted site

 Subsided site

EXPLANATION

LiDAR-identified topographic features:

Fault scarp (field checked) 

Possible fault scarp

Topographic lineament

Paleoseismic trench (see text

and Table 2 for references)

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)
Nooksack River

Skagit River

Stillaguamish River

Snohomish River

Skykomish River

Snoqualmie River

Cedar River

Green River

Puyallup River

Puyallup R.

White River

Carbon River

Nisqually River

Skokomish River

Quilcene River

Dosewallips River

Duckabush River

Chehallis River

Satsop

River

Deschutes River

Black River

Quinalt R.

Elwah

River

BELLINGHAM

EVERETT

SEATTLE

TACOMA

OLYMPIA

VICTORIA

CANADA

U.S.A.

20 Miles 20 Km 1:600,000

47°

47°30’

46°50’

48°

48°30’

123°30’ 123° 122°30’ 122° 121°30’

49°

MAP 2: SEISMIC SURVEY LOCATIONS IN PUGET LOWLAND

PUGET SOUND

STRAIT OF JUAN DE FUCA

GEORGIA STRAIT

OLYM

PIC

M

O

UNTA

N

I

S

CASCA

D

E

RAN

GE

Mount Rainier

Mount Baker

VANCOUVER 

ISLAND

Area of Inset Map 4

Pratt and others, 1997

Brocher and others, 2001; 

Fisher and others, 1999

Rohwer, 1994

Johnson and others, 2004d

Johnson and others, 1999

Brocher and others, 2000b

Liberty and others, 2008

Pratt, written comm., 2008

Stephenson and others, 2006

Stephenson, written comm., 2008

Liberty and Pratt, 2007

Cuellar, 1994

Pape, written comm., 2008

Sherrod and others, 2007;

Brocher and others, 2003

Luetgert and others, 1993;

Miller and others, 1997

SEISMIC SURVEY LOCATIONS KEY

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)

EXPLANATION

Deformation observed in seismic 

reflection data:

Johnson and others, 2001c

Johnson and others, 1996

Johnson and others, 1999

Pratt and others, 1997

Johnson and others, 2004d

Paleoseismic trench (see text

and Table 2 for references)

Lidar-identified fault scarp 
SEATTLE

TACOMA

123°15’ 123° 122°30’ 122°

47°19’

47°30’

47°50’

Cedar R.

Quilcene R.

Dosewallips R.

Duckabush R.

Duwamish R.

Green R.

10 Miles

10 Km 1:400,000

INSET MAP 4: SEISMIC SURVEY LOCATIONS

IN SEATTLE/TACOMA REGION

SEISMIC SURVEY LOCATIONS KEY

Liberty and others, 2008

Pratt, written comm., 2008

Stephenson and others, 2006

Stephenson, written comm., 2008

Liberty and Pratt, 2007

Johnson and others, 2004c

Johnson and others, 1999

Cuellar, 1994

Pape, written comm., 2008;

 Sherrod and others, 2008

Brocher and others, 2000b

Rohwer, 1994

Pratt and others, 1997

Brocher and others, 2001; 

 Fisher and others, 1999

Luetgert and others, 1993;

 Miller and others, 1997

EXPLANATION

Deformation observed in seismic 

reflection data:

Johnson and others, 1999

Pratt and others, 1997

Johnson and others, 2004c

LiDAR-identified topographic features:

Fault scarp (field checked) 

Possible fault scarp

Topographic lineament

Paleoseismic trench (see text

and Table 2 for references)

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)

Catfish Lake

Bainbridge 

Island

 

Cottage Lake

Vasa Park

Saddle MntPrice Lake

Sunset Beach

Frigid Creek

Waterman Pt

SEATTLE

TACOMA

123°15’ 123° 122°30’ 122°

47°19’

47°30’

47°50’

Cedar R.

Quilcene R.

Dosewallips R.

Duckabush R.

Duwamish R.

Green R.

10 Miles

10 Km 1:400,000

INSET MAP 3: PALEOSEISMIC STUDIES IN SEATTLE/TACOMA REGION

2000-2007 Puget Sound Lidar Consortium 

2006 Snohomish County survey

2003 King County data

PUGET SOUND LIDAR DATA SOURCES:

Paleoseismic coastal study site:

Bucknam, 1999 

Sherrod 1998, 2001:

 Uplifted site

 Subsided site

EXPLANATION

LiDAR-identified topographic features:

Fault scarp (field checked) 

Possible fault scarp

Topographic lineament

Paleoseismic trench (see text

and Table 2 for references)

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)

Traingles denote Uplift (m)

8.5 

1 

7

3 

5

SHORELINE UPLIFT

LiDAR-modeled 

shoreline uplift 

during AD 900 Seattle 

Fault earthquake

(Muller and Harding, 

2005)
300

600

1500

900

1200

1800

2400

2700

2100

3000

3600

3300

100

600

300

300

100

100

300

300

2400

100

100

100

900

3300

100

100

100

3000

1800

100

100

100

300

100

1200

600

300

600

300

900

600

1500

1200

2700

1200

900

1800

1500

300

3300

2100

100

600

100

100

100

1500

100

300

100

100

1500

100

900

2400

100

300

100

900

100

900

2400

100

100

300

100

1800

100

600

100

300

2400

100

300

100

300

100

900

100

300

1500

100

2100

100

1200

300

100

100

1800

600

100

300

100

600

1500

100

600

100

100

300

3300

600

1200

300

2400

100

300

1800

2100

300

100

600

100

300

100

1200

1200

300

900

300

300

600

100

1800

300

900 1800

100

100

900

100

1500

2400

1200

100

1800

300

600

1500

900

1200

1800

2400

2700

2100

3000

3600

3300

100

600

300

300

100

100

300

300

2400

100

100

100

900

3300

100

100

100

3000

1800

100

100

100

300

100

1200

600

300

600

300

900

600

1500

1200

2700

1200

900

1800

1500

300

3300

2100

100

600

100

100

100

1500

100

300

100

100

1500

100

900

2400

100

300

100

900

100

900

2400

100

100

300

100

1800

100

600

100

300

2400

100

300

100

300

100

900

100

300

1500

100

2100

100

1200

300

100

100

1800

600

100

300

100

600

1500

100

600

100

100

300

3300

600

1200

300

2400

100

300

1800

2100

300

100

600

100

300

100

1200

1200

300

900

300

300

600

100

1800

300

900

1800

100

100

900

100

1500 2400

1500

600

1800

TACOMA BASIN

SEATTLE BASIN

EVERETT BASIN

BELLINGHAM

EVERETT

SEATTLE

TACOMA

OLYMPIA

VICTORIA

CANADA

U.S.A.

20 Miles 20 Km 1:600,000

47°

47°30’

46°50’

48°

48°30’

123°30’ 123° 122°30’ 122° 121°30’

49°

MAP 5: THICKNESS OF UNCONSOLIDATED QUATERNARY DEPOSITS IN PUGET LOWLAND

OLYM

PIC

M

O

UNTA

N

I

S

CASCA

D

E

RAN

GE

VANCOUVER 

ISLAND

Area of Inset Map 6

100

300

600

900

1200

1500

1800

2100

2400

2700

3000

3300

3600

Thickness

contour lines

Well or 

seismic shot 

locations

Area of mapped bedrock outcrop, 

modfied from Jones (1996).

Color-shaded relief of generalized 

bedrock surface beneath Quaternary 

deposits. Color represents deposit 

thickness (depth to bedrock), as 

extrapolated from well and shot data. 

Thickness in feet inferred from oil, coal, or 

gas well, or marine seismic reflection shot 

point data (well locations and contour lines 

modified from Jones, 1996)

THICKNESS OF UNCONSOLIDATED QUATERNARY

DEPOSITS

Paleoseismic trench 

Lidar-identified fault scarp 
122°10'

122°10'

122°20'

122°20'

30'

30'

122°40'

122°40'

122°50'

122°50'

123°

123°

123°10'

123°10'

122°

47°50'

45'

45'

47°40'

47°40'

47°35'

47°35'

30'

30'

47°25'

47°25'

47°20'

47°20'

36 0 0

33 0 0

90 0

10 0

10 0

30 0

12 0 0

60 0

90 0

18 0 0

15 0 0

10

0

10 0

15 0 0

90 0

10 0

90 0

30 0

15 0 0

21 0 0

30 0

10 0

30 0

15 0 0

10 0

10 0

24 0 0

30 0

10 0

12 0 0

18 0 0

18 0 0

15 0 0

18 0 0

36 0 0

33 0 0

90 0

10 0

10 0

30 0

12 0 0

60 0

90 0

18 0 0

15 0 0

10 0

10 0

15 0 0

90 0

10 0

90 0

30 0

15 0 0

21 0 0

30 0

10 0

30 0

15 0 0

10 0

10 0

24 0 0

30 0

10 0

12 0 0

18 0 0

18 0 0

15 0 0

18 0 0

SEATTLE

TACOMA

SEATTLE BASIN

123°15’ 123° 122°30’ 122°

47°30’

47°50’

47°19’

10 Miles

10 Km 1:400,000

INSET MAP 6: THICKNESS OF UNCONSOLIDATED QUATERNARY DEPOSITS IN SEATTLE/TACOMA REGION

Paleoseismic trench 

Lidar-identified fault scarp 

100

300

600

900

1200

1500

1800

2100

2400

2700

3000

3300

3600

Thickness

contour lines

Well or 

seismic shot 

locations

Area of mapped bedrock outcrop, 

modfied from Jones (1996).

Color-shaded relief of generalized 

bedrock surface beneath Quaternary 

deposits. Color represents deposit 

thickness (depth to bedrock), as 

extrapolated from well and shot data. 

Thickness in feet inferred from oil, coal, or 

gas well, or marine seismic reflection shot 

point data (well locations and contour lines 

modified from Jones, 1996)

THICKNESS OF UNCONSOLIDATED QUATERNARY

DEPOSITS
BELLINGHAM

EVERETT

SEATTLE

TACOMA

OLYMPIA

VICTORIA

CANADA

U.S.A.

20 Miles 20 Km 1:600,000

47°

47°30’

46°50’

48°

48°30’

123°30’ 123° 122°30’ 122° 121°30’

49°

MAP 7: AEROMAGNETIC ANOMALIES IN PUGET LOWLAND

Area of Inset Map 9

271.9

139.8

77.9

33.5

-5.0

-41.7

-79.5

-118.4

-149.1

-175.3

-198.0

-216.9

-235.9

-262.0

-311.9

Magnetic Anomaly (nT)

Blakely and others, 1999

Aeromagnetic lineament along 

South Whidbey Island Fault Zone

(Sherrod and others, 2008)

++++++++++++++

 Paleoseismic trench 

LiDAR-identified fault scarps

EXPLANATION

Locations of sharp magnetic contrasts, 

estimated from magnetic anomalies

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)
BELLINGHAM

EVERETT

SEATTLE

TACOMA

OLYMPIA

VICTORIA

CANADA

U.S.A.

20 Miles 20 Km 1:600,000

47°

47°30’

46°50’

48°

48°30’

123°30’ 123° 122°30’ 122° 121°30’

49°

MAP 8: RESIDUAL AEROMAGNETIC ANOMALIES IN PUGET LOWLAND

Area of Inset Map 10

Residual Magnetic 

Anomaly (nT)

Blakely and others, 1999

7.8

3.6

2.0

1.1

0.5

0.0

-0.3

-0.6

-0.9

-1.2

-1.6

-2.1

-2.8

-4.2

-7.1

Paleoseismic trench 

LiDAR-identified fault scarps

EXPLANATION

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)
SEATTLE

TACOMA

123°15’ 123° 122°30’ 122°

47°19’

47°30’

47°50’

10 Miles

10 Km 1:400,000

INSET MAP 10: RESIDUAL AEROMAGNETIC ANOMALIES

IN SEATTLE/TACOMA REGION Paleoseismic trench 

LiDAR-identified fault scarps

EXPLANATION

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN) Residual Magnetic 

Anomaly (nT)

Blakely and others, 1999

7.8

3.6

2.0

1.1

0.5

0.0

-0.3

-0.6

-0.9

-1.2

-1.6

-2.1

-2.8

-4.2

-7.1

SEATTLE

TACOMA

123°15’ 123° 122°30’ 122°

47°30’

47°50’

47°19’

10 Miles

10 Km 1:400,000

INSET MAP 9: AEROMAGNETIC ANOMALIES

IN SEATTLE/TACOMA REGION

271.9

139.8

77.9

33.5

-5.0

-41.7

-79.5

-118.4

-149.1

-175.3

-198.0

-216.9

-235.9

-262.0

-311.9

Magnetic Anomaly (nT)

Blakely and others, 1999

Aeromagnetic lineament along 

South Whidbey Island Fault Zone

(Sherrod and others, 2008)

++++++++++++++

 Paleoseismic trench 

LiDAR-identified fault scarps

EXPLANATION

Locations of sharp magnetic contrasts, 

estimated from magnetic anomalies

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)
BELLINGHAM

EVERETT

SEATTLE

TACOMA

OLYMPIA

VICTORIA

CANADA

U.S.A.

20 Miles 20 Km 1:600,000

47°

47°30’

46°50’

48°

48°30’

123°30’ 123° 122°30’ 122° 121°30’

49°

MAP 11: ISOSTATIC RESIDUAL GRAVITY ANOMALIES IN PUGET LOWLAND

Area of Inset Map 12

38.8

23.0

10.4

2.9

-2.6

-6.6

-9.9

-13.3

-16.7

-19.7

-22.8

-26.4

-30.9

-37.1

-45.6

Isostatic Residual

Gravity (mGal) Finn and others, 1991

Station location

EXPLANATION

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)

Paleoseismic trench 

LiDAR-identified fault scarps

Locations of sharp gravity contrasts, 

estimated from gravity anomalies
SEATTLE

TACOMA

123°15’ 123° 122°30’ 122°

47°19’

47°30’

47°50’

10 Miles

10 Km 1:400,000

INSET MAP 12: ISOSTATIC RESIDUAL GRAVITY ANOMALIES

IN SEATTLE/TACOMA REGION 38.8

23.0

10.4

2.9

-2.6

-6.6

-9.9

-13.3

-16.7

-19.7

-22.8

-26.4

-30.9

-37.1

-45.6

Isostatic Residual

Gravity (mGal) Finn and others, 1991

Station location

EXPLANATION

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)

Paleoseismic trench 

LiDAR-identified fault scarps

Locations of sharp gravity contrasts, 

estimated from gravity anomalies
1500

900

1200

2400

2700

3000

3600

3300

2400

3300

3000

1800

1200

900

1500

1200

2700

1200

900

1800

1500

3300

2100

100

1500

1500

900

2400

100

900

900

2400

1800

2400

100

900

1500

2100

12

1800

1500

3300

1200

300

2400

100

1800

2100

1200

1200

1200

900

900

1800

900

2400

1500

1800

00

100

100

300

BELLINGHAM

EVERETT

SEATTLE

TACOMA

OLYMPIA

VICTORIA

CANADA

U.S.A.

Georgia Strait

Puget Sound

Juan de Fuca Strait

Catfish Lake

Bainbridge 

Island

 

Frigid 

Creek

Cottage Lake

Vasa Park

Kendall

Sunset Beach

Saddle MntPrice Lake

Lake CreekBoundary Creek 

Smuggler

Canyon 

River

Rocky Point Whitman Bench

Waterman Pt

Lake Creek

TACOMA BASIN

SEATTLE BASIN

EVERETT BASIN

STRAWBERRY POINT FAULT1

UTSALADY POINT FAULT1

LAKE CREEK

BOUNDARY

-

 CREEK FAULT1

BOULDER CREEK

 FAULT6

HOOD CANAL FAULT1

SADDLE MNT

FAULT ZONE1 SEATTLE F AULT ZONE1

TACOMA FAULT ZONE1,3,4

SOUTHERN WHIDBEY

ISLAND FAULT ZONE1,5,7

CANYON R.

FAULT1

MACAULAY CR. FAULT1

- DEVILS MOUNTAIN FAULT ZONE1

DARRINGTON 

SEATTLE UPLIFT

OLYMPIA FAULT2

20 Miles 20 Km 1:600,000

47°

47°30’

46°50’

48°

48°30’

123°30’ 123° 122°30’ 122° 121°30’

49°

Area of Inset Map 14

 

 Holocene-active faults documented by

 paleoseismic studies 

 Quaternary-active faults

 (Holocene activity unknown or uncertain)

 Seismic profile-identified fault, 

 possibly Quaternary-active

 1 USGS Quatermary Fault Database 

 2Sherrod, 2001

 3Brocher and others, 2001 

 4Johnson and others, 2004c

 5Sherrod and others, 2008

 6Haugerud and others, 2005; Barnett, 2007;

 Barnett and others, 2007

 7Kelsey and others, 2004

Sources for fault trace locations (also see Table 1):

 QUATERNARY FAULT TRACES

Johnson and others, 2001b

Johnson and others, 1996

Johnson and others, 1999

Pratt and others, 1997

Johnson and others, 2004c

Deformation interpreted on 

seismic lines to result from motion 

on Quaternary fault systems

Contour lines denote thickness of 

unconsolidated Puget Sound basin deposits

(Jones, 1996)

Aeromagnetic lineament along 

South Whidbey Island Fault Zone

(Sherrod and others, 2008)

Locations of sharp gravity contrasts, 

estimated from gravity anomalies

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)

Paleoseismic coastal 

Sherrod 1998, 2001:

 Uplifted site

 Subsided site

EXPLANATION

 LiDAR-identified fault scarp

Paleoseismic trench (see text

and Table 2 for references)

MAP 13: SUMMARY OF SHALLOW FAULT DEFORMATION DATA AND QUATERNARY FAULT TRACES IN

PUGET LOWLAND, DRAPED OVER RESIDUAL AEROMAGNETIC ANOMALIES

Residual Magnetic 

Anomaly (nT)

Blakely and others, 1999

7.8

3.6

2.0

1.1

0.5

0.0

-0.3

-0.6

-0.9

-1.2

-1.6

-2.1

-2.8

-4.2

-7.1
3 6 0 0

3 3 0 0

1 2 0 0

9 0

1 8 0 0

1 5 0 0

1 5 0 0

9 0 0

1 5 0 0

2 1 0 0

1 5 0 0

2 4 0 0

1 2 0 0

1 8 0 0

1 8 0 0

3 6 0 0

3 3 0 0

1 2 0 0

9 0

1 8 0 0

1 5 0 0

1 5 0 0

9 0 0

1 5 0 0

2 1 0 0

1 5 0 0

2 4 0 0

1 2 0 0

1 8 0 0

1 8 0 0

10 0

10 0

30 0

30 0

10 0

10 0

30 0

30 0

10

Catfish Lake

Bainbridge 

Island

 

Cottage Lake

Vasa Park

Saddle MntPrice Lake

Sunset Beach

Frigid Creek

SEATTLE

TACOMA

Puget Sound

SEATTLE UPLIFT

SEATTLE FAULT ZONE1

TACOMA FAULT ZONE1,2,3

HOOD

CANAL

FAU

LT1

SOUTH WHIDBEY ISLAND FAULT ZONE1,4,5

SADDLE MNT

FAULT ZONE1

123°15’ 123° 122°30’ 122°

47°19’

47°30’

47°50’

10 Miles

10 Km 1:400,000

INSET MAP 14: SUMMARY OF SHALLOW FAULT DEFORMATION DATA AND QUATERNARY

FAULT TRACES IN SEATTLE/TACOMA REGION, DRAPED OVER RESIDUAL AEROMAGNETIC ANOMALIES

 

 Holocene-active faults documented by

 paleoseismic studies 

 Quaternary-active faults

 (Holocene activity unknown or uncertain)

 1 USGS Quatermary Fault Database 

 2

Brocher and others, 2001 

 3Johnson and others, 2004c

 4Sherrod, and others, 2008

 5Kelsey and others, 2004

 

Sources for fault trace locations (also see Table 1):

 QUATERNARY FAULT TRACES

Johnson and others, 1999

Pratt and others, 1997

Johnson and others, 2004c

Deformation interpreted on 

seismic lines to result from motion 

on Quaternary fault systems

Contour lines denote thickness of 

unconsolidated Puget Sound basin deposits

(Jones, 1996)

Aeromagnetic lineament along 

South Whidbey Island Fault Zone

(Sherrod and others, 2008)

Locations of sharp gravity contrasts, 

estimated from gravity anomalies

Paleoseismic coastal 

Sherrod 1998, 2001:

 Uplifted site

 Subsided site

EXPLANATION

 LiDAR-identified fault scarp

Paleoseismic trench (see text

and Table 2 for references)

Residual Magnetic 

Anomaly (nT)

Blakely and others, 1999

7.8

3.6

2.0

1.1

0.5

0.0

-0.3

-0.6

-0.9

-1.2

-1.6

-2.1

-2.8

-4.2

-7.1

Magnitude 5.0 4.0 3.0 

Depth 0-35 km

Earthquakes 1970-present, Pacific 

Northwest Seismic Network (PNSN)