Linn County Earthquake Scenarios, Geologic Hazard Maps, and HAZUS

Oregon Department of Geology and Mineral Industries Interpretive Map Series 24

Geologic Hazards, Earthquake and Landslide Hazard Maps, and Future Earthquake Damage Estimates for Six Counties in the Mid/Southern Willamette Valley Including Yamhill, Marion, Polk, Benton, Linn, and Lane Counties and the City of Albany, Oregon

APPENDIX D: Linn County

Crustal Earthquake Scenario Scenario Details Ground Motion Map

Subduction Zone Earthquake Scenario Scenario Details Ground Motion Map

Geologic Hazard Maps Relative Ground-Shaking Amplification Susceptibility Map Relative Liquefaction Hazard Susceptibility Map Relative Earthquake-Induced Landslide Susceptibility Map Identified Landslide Areas Map

HAZUS-MH Global Report for Crustal Scenario HAZUS-MH Global Report for Subduction Zone Scenario

Mid/Southern Willamette Valley, Geologic Hazards, Earthquake and Landslide Hazard Maps, and Future Earthquake Damage Estimates

Crustal Earthquake Scenario Details for Linn County

Crustal Earthquake Scenario: A magnitude 6.7 earthquake on the Mill Creek Fault.

For the magnitude 6.7 earthquake on the Mill Creek Fault scenario, we defined the fault source using the “de- terministic seismic source” option within HAZUS-MH (Figure D1) (FEMA, 2003b). The fault and earthquake event were chosen by examination of USGS (2004) data and data in the Geomatrix Consultants, Inc. (1995) Seismic Design Mapping, State of Oregon report prepared for the Oregon Department of Transportation. In general, a likely worst-case scenario was selected. Figure D1 has the location of the fault, shown as the dark line, and the census tracts within Linn County. Figure D2 displays the peak ground acceleration (PGA) for the crustal scenario.

Scenario Name Mill Creek M6.7 Type of Earthquake Source Fault Name Mill Creek Fault Historical Epicenter ID # 70 Probabilistic Return Period NA Longitude of Epicenter −123.015 Latitude of Epicenter 44.7428 Earthquake Magnitude 6.7 Depth (km) 0.00 Rupture Length (km) 27.11 Rupture Orientation (degrees) 0.00 Attenuation Function Reverse-Slip

Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D3 Mid/Southern Willamette Valley Geologic Hazards, Earthquake and Landslide Hazard Maps, and Future Earthquake Damage Estimates

Figure D1. Mill Creek Fault details from HAZUS-MH (FEMA, 2003b). The location of the fault is shown as the dark line.

D4 Appendix D: Linn County Oregon Department of Geology and Mineral Industries IMS-24 Mid/Southern Willamette Valley, Geologic Hazards, Earthquake and Landslide Hazard Maps, and Future Earthquake Damage Estimates

Crustal Earthquake Scenario Ground Motion Map

Marion County

Mill Creek Fault

Polk County

Albany

Lebanon

Lane County

Highway or Interstate Mill Creek Fault 02.5 5 10 City Outline PGA (g) by Census Tract . Miles County Outline 0.0 - 0.1 05 10 20 River 0.1 - 0.2 Kilometers 0.2 - 0.3 0.3 - 0.4 0.4 - 0.5 0.5+

Figure D2. Peak ground acceleration (PGA) by census tracts map for the crustal earthquake scenario, Linn County, Oregon (FEMA, 2003b).

Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D5 Mid/Southern Willamette Valley Geologic Hazards, Earthquake and Landslide Hazard Maps, and Future Earthquake Damage Estimates

Subduction Zone Earthquake Scenario Details for Linn County

Subduction Zone Scenario: A magnitude 9.0 earthquake on the Cascadia Subduction Zone was selected for the subduction zone earthquake scenario.

For the Cascadia Subduction Zone earthquake scenario, we used the “user-defined event” option within HA- ZUS-MH to incorporate ground motion maps developed by the Cascadia Region Earthquake Workgroup (CREW, 2003) to model damage and loss from a magnitude 9.0 earthquake (Figure D3). The CREW maps were developed from ground motion data provided by the U.S. Geological Survey. The CREW earthquake scenario required the input of four sets of GIS files that are included within the HAZUS-MH study region: regional peak ground acceleration (PGA), peak ground velocity (PGV), and the spectral velocity at 0.3 s and 1.0 s (CREW, 2003). Figure D4 displays the PGA for the subduction zone scenario.

Figure D3. Location of the Cascadia Subduction Zone (CREW, 2003).

D6 Appendix D: Linn County Oregon Department of Geology and Mineral Industries IMS-24 Mid/Southern Willamette Valley, Geologic Hazards, Earthquake and Landslide Hazard Maps, and Future Earthquake Damage Estimates

Subduction Zone Earthquake Scenario Ground Motion Map

Marion County

Polk County

Albany

Lebanon

Lane County

Highway or Interstate PGA (g) by Census Tract 02.5 5 10 City Outline 0.0 - 0.1 . Miles County Outline 0.1 - 0.2 05 10 20 River 0.2 - 0.3 Kilometers 0.3 - 0.4 0.4 - 0.5 0.5+

Figure D4. Peak ground acceleration (PGA) by census tracts map for the Cascadia Subduction Zone earthquake scenario, Linn County, Oregon (FEMA, 2003b).

Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D7 Mid/Southern Willamette Valley Geologic Hazards, Earthquake and Landslide Hazard Maps, and Future Earthquake Damage Estimates

Geologic Hazard Maps

Relative Ground-Shaking Amplification Susceptibility Map

Marion County

Po k County

Albany

Lebanon

Lane County

County Outline Ground Shaking Amplification 02.5 5 10 Highway or Interstate (NEHRP Site Class) . Miles City Outline Very Low (A) 05 10 20 Low (B) Kilometers Moderate (C) High (D) Very High (E and F)

Figure D5. Relative ground-shaking amplification susceptibility map for Linn County, Oregon.

D8 Appendix D: Linn County Oregon Department of Geology and Mineral Industries IMS-24 Mid/Southern Willamette Valley, Geologic Hazards, Earthquake and Landslide Hazard Maps, and Future Earthquake Damage Estimates

Relative Liquefaction Hazard Susceptibility Map

Marion County

Polk County

Albany

Lebanon

Lane County

County Outline Liquefaction Susceptibility 02.5 5 10 Highway or Interstate Rare Miles Very Low . City Outline 05 10 20 Low Kilometers Moderate High Very High

Figure D6. Relative liquefaction susceptibility map for Linn County, Oregon.

Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D9 Mid/Southern Willamette Valley Geologic Hazards, Earthquake and Landslide Hazard Maps, and Future Earthquake Damage Estimates

Relative Earthquake-Induced Landslide Susceptibility Map

Marion County

Polk County

Albany

Lebanon

Lane County

County Outline Landslide Susceptibility 02.5 5 10 Highway or Interstate Low . Miles City Outline Moderate 05 10 20 High Kilometers Very High

Figure D7. Relative earthquake-induced landslide susceptibility map for Linn County, Oregon.

D10 Appendix D: Linn County Oregon Department of Geology and Mineral Industries IMS-24 Mid/Southern Willamette Valley, Geologic Hazards, Earthquake and Landslide Hazard Maps, and Future Earthquake Damage Estimates

Identified Landslide Areas Map

Marion County

Polk County

Albany Lebanon

Lane County

Highway or Interstate Identified Landslide Areas 02.5 5 10 City Outline . Miles County Outline 05 10 20 River Kilometers

Figure D8. Identified landslide map for Linn County, Oregon.

Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D11

Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D13

   

   

    

    

                                                                              Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D14

  

                                                                      

              

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D15

    

                                                                           

                    



             

                                                

                                       

                     

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D16

     

                                     

                                 

                                              

                                                                        

    

                                                             

                          

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D17

                                                                                        

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D18

                                                                                   

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D19

 

                     

                          

   

     

   

           

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D20

                                                                                     

      

    

         

                                                                                               

          

                                                                                                 

         

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D21

                                                                

      

 

                     

    

    

    

    

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D22

    

        

       

                                            

                        

                         

      

      

      

            

                                 

                                                             

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D23

       

                        

      

      

      

      

      

     

         

                             

         

                 

              

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D24

  

                                                                                                 

                                               

                                                         

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D25

 

                                                                

                                      

                                                 

                                                                       

           

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D26

   

       

      

    

    

    

    

    

     

    

      

    

    

    

    

    

     

    

      

    

    

    

    

    

     

    

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D27

 

                                    

 

                                                                             

                                                          

        

                                                                                           

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D28

                                                

                                         

        

        

                                                                                               

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D29

        

        

              

  

              

  

              

  

         

  

     

  

    

     

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D30

                  

                                                                

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D31

       

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D32

       

                             

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D33

   

   

   

    

  

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D35

    



        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D36

     

    

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D37

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D38

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D39

 

                       

   

     

   

      

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D40

                                                                                     

      

    

         

                                                                                               

          

                                                                                                 

         

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D41

                                                                

      

 

                     

    

    

    

    

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D42

    

        

       

                                            

                        

      

      

      

            

                                                             

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D43

       

      

      

      

      

      

     

         

                             

         

              

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D44

  

                                                                                                 

                                                         

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D45

 

                                                                

                                      

                                                 

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D46

   

       

      

    

    

    

    

    

     

    

      

    

    

    

    

    

     

    

      

    

    

    

    

    

     

    

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D47

 

                                    

 

                                                          

                                                                                           

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D48

                                         

        

        

                                                                                               

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D49

        

        

              

  

              

  

              

  

         

  

     

  

    

     

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D50

                                                                

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D51

       

        Oregon Department of Geology and Mineral Industries IMS-24 Appendix D: Linn County D52

       

       