Tsunami Inundation Map for Emergency Planning

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California Emergency Management Agency Tsunami Inundation Map for Emergency Planning State of California California Geological Survey White Ledge Peak Quadrangle County of Santa Barbara University of Southern California 119°30'0"W 119°22'30"W E L E L G N G A N R A G R D D A A U U Q Q

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N N T N S K O M O N H L A Y Y T C IL A O O E N E N M N P N P A IN A H M C A E N O A O A P C T R IC E P N Y A N S R C I S E R E L O R O N N D O I H A A N L L L M U IM A Y A E K H R A C W L H I T E C M

N N O O M N N A Y T A Y L E I A N O N A P R D A M Y N M A A U A L C A N T A C S L L T M Y M T M T I A U A R A E E N C K IN D A H C Y E A T C U A S A U G O N Q Z E E W C N P U A IT S N T P E I G S W U A A N L T P M B L E A T B O K R N E C R K A O E E T A I T C Y K N D N E L T N T O T P A O A A M E P U U L N M A M C Q C D Y S A L A R X M R IS N C IC U O A A O S E A A F Y C X Z B R B U O R IS F U L C H A S K E N E N T K R S K S T N A C O E M T E C E O M L M P O F O M IV A E V R P A R L E E E L C O A N C U U M A O R F I L S O A E A P N L S C S R U O A O U IG D O L Z L IG N B A H F A M C S N A R N O IN S S I L A S L A S IN K A L T L IL A A A T N Z M P N E IL H G E U T E U U U H A N N H S N P G O S Y C O U H O R M C A C O T M O O V A A A N R L T C R M E N T P O N A R A O M A S E E D IN L T A K M N M L O N S N I IL O I L A P H D P U A L A E L Q S S L O N T A N T N O I K R Y L T IO A A T N R A E P A A I P A S C B R E E T A A E E C T U S T R T G N A IO O E A D 34°22'30"N C IG L L IN 34°22'30"N O V B P E C A A J B O A L S G A E G T R E T T U A N N C IT I P A H O S S P O W D

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PITAS POINT QUADRANGLE

119°30'0"W 119°22'30"W

METHOD OF PREPARATION TSUNAMI INUNDATION MAP MAP EXPLANATION

Initial tsunami modeling was performed by the University of Southern California (USC) FOR EMERGENCY PLANNING Tsunami Research Center funded through the California Emergency Management Agency Tsunami Inundation Line (CalEMA) by the National Tsunami Hazard Mitigation Program. The tsunami modeling process utilized the MOST (Method of Splitting Tsunamis) computational program (Version 0), which allows for wave evolution over a variable bathymetry and topography Tsunami Inundation Area used for the inundation mapping (Titov and Gonzalez, 1997; Titov and Synolakis, 1998). State of California ~ County of Santa Barbara

The bathymetric/topographic data that were used in the tsunami models consist of a series of nested grids. Near-shore grids with a 3 arc-second (75- to 90-meters) WHITE LEDGE PEAK QUADRANGLE resolution or higher, were adjusted to “Mean High Water” sea-level conditions, representing a conservative sea level for the intended use of the tsunami modeling PURPOSE OF THIS MAP and mapping. This tsunami inundation map was prepared to assist cities and counties in identifying their tsunami hazard. It is intended for local jurisdictional, coastal evacuation A suite of tsunami source events was selected for modeling, representing realistic January 31, 2009 planning uses only. This map, and the information presented herein, is not a legal local and distant earthquakes and hypothetical extreme undersea, near-shore landslides document and does not meet disclosure requirements for real estate transactions (Table 1). Local tsunami sources that were considered include offshore reverse-thrust nor for any other regulatory purpose. faults, restraining bends on strike-slip fault zones and large submarine landslides capable of significant seafloor displacement and tsunami generation. Distant tsunami The inundation map has been compiled with best currently available scientific sources that were considered include great subduction zone events that are known to SCALE 1:24,000 information. The inundation line represents the maximum considered tsunami runup have occurred historically (1960 Chile and 1964 Alaska earthquakes) and others which 0.5 0.25 0 0.5 1 from a number of extreme, yet realistic, tsunami sources. Tsunamis are rare events; can occur around the Pacific Ocean “Ring of Fire.” Miles due to a lack of known occurrences in the historical record, this map includes no information about the probability of any tsunami affecting any area within a specific In order to enhance the result from the 75- to 90-meter inundation grid data, a method 1,000 500 0 1,000 2,000 3,000 4,000 5,000 period of time. was developed utilizing higher-resolution digital topographic data (3- to 10-meters Feet resolution) that better defines the location of the maximum inundation line (U.S. Please refer to the following websites for additional information on the construction Geological Survey, 1993; Intermap, 2003; NOAA, 2004). The location of the enhanced 0.5 0.25 0 0.5 1 and/or intended use of the tsunami inundation map: inundation line was determined by using digital imagery and terrain data on a GIS Kilometers platform with consideration given to historic inundation information (Lander, et al., State of California Emergency Management Agency, Earthquake and Tsunami Program: 1993). This information was verified, where possible, by field work coordinated with http://www.oes.ca.gov/WebPage/oeswebsite.nsf/Content/B1EC local county personnel. 51BA215931768825741F005E8D80?OpenDocument The accuracy of the inundation line shown on these maps is subject to limitations in Table 1: Tsunami sources modeled for the Santa Barbara County coastline. University of Southern California – Tsunami Research Center: the accuracy and completeness of available terrain and tsunami source information, and http://www.usc.edu/dept/tsunamis/2005/index.php the current understanding of tsunami generation and propagation phenomena as expressed Areas of Inundation Map Coverage and Sources Used in the models. Thus, although an attempt has been made to identify a credible upper Sources (M = moment magnitude used in modeled State of California Geological Survey Tsunami Information: Santa bound to inundation at any location along the coastline, it remains possible that actual event) Santa http://www.conservation.ca.gov/cgs/geologic_hazards/Tsunami/index.htm Lompoc Barbara – inundation could be greater in a major tsunami event. Barbara Ventura National Oceanic and Atmospheric Agency Center for Tsunami Research (MOST model): Anacapa-Dume Fault X This map does not represent inundation from a single scenario event. It was created by http://nctr.pmel.noaa.gov/time/background/models.html Channel Island Thrust Fault X X combining inundation results for an ensemble of source events affecting a given region Local Goleta Offshore Landslide #1 X X (Table 1). For this reason, all of the inundation region in a particular area will not likely Sources be inundated during a single tsunami event. Goleta Offshore Landslide #2 X X 1927 Point Arguello Earthquake (M7.3) X Central Aleutians Subduction Zone#1 (M8.9) X X References: MAP BASE Central Aleutians Subduction Zone#2 (M8.9) X Intermap Technologies, Inc., 2003, Intermap product handbook and quick start guide: Central Aleutians Subduction Zone#3 (M9.2) X X X Topographic base maps prepared by U.S. Geological Survey as part of the 7.5-minute Intermap NEXTmap document on 5-meter resolution data, 112 p. Chile North Subduction Zone (M9.4) X X X Quadrangle Map Series (originally 1:24,000 scale). Tsunami inundation line 1960 Chile Earthquake (M9.3) X X Distant boundaries may reflect updated digital orthophotographic and topographic data that 1964 Alaska Earthquake (M9.2) X X Lander, J.F., Lockridge, P.A., and Kozuch, M.J., 1993, Tsunamis Affecting the West Coast Sources can differ significantly from contours shown on the base map. of the United States 1806-1992: National Geophysical Data Center Key to Geophysical Cascadia Subduction Zone #2 (M9.2) X Record Documentation No. 29, NOAA, NESDIS, NGDC, 242 p. Japan Subduction Zone #2 (M8.8) X Kuril Islands Subduction Zone #2 (M8.8) X National Atmospheric and Oceanic Administration (NOAA), 2004, Interferometric Kuril Islands Subduction Zone #3 (M8.8) X Synthetic Aperture Radar (IfSAR) Digital Elevation Models from GeoSAR platform (EarthData): Kuril Islands Subduction Zone #4 (M8.8) X DISCLAIMER 3-meter resolution data. The California Emergency Management Agency (CalEMA), the University of Southern Titov, V.V., and Gonzalez, F.I., 1997, Implementation and Testing of the Method of Tsunami California (USC), and the California Geological Survey (CGS) make no representation Splitting (MOST): NOAA Technical Memorandum ERL PMEL – 112, 11 p. or warranties regarding the accuracy of this inundation map nor the data from which the map was derived. Neither the State of California nor USC shall be liable under any Titov, V.V., and Synolakis, C.E., 1998, Numerical modeling of tidal wave runup: circumstances for any direct, indirect, special, incidental or consequential damages Journal of Waterways, Port, Coastal and Ocean Engineering, ASCE, 124 (4), pp 157-171. with respect to any claim by any user or any third party on account of or arising from the use of this map. U.S. Geological Survey, 1993, Digital Elevation Models: National Mapping Program, Technical Instructions, Data Users Guide 5, 48 p.