USGS - science for a changing world

Pacific Coastal and Marine Science Center

Coastal and Marine Earthquake, Tsunami, and Landslide Active Margin Field Studies

See also:

Overview

As the population continues to migrate toward the coastlines, the societal impacts of these hazards are expected to grow. Recent giant earthquakes that spawned pan-oceanic tsunamis have revealed the vulnerability of U. S. coasts to such natural disasters. The highest priorities for regional active margin field studies are in direct response to the aftermath of the 2011 Japan 9.0 earthquake and tsunami: 1) a re-assessment of the hazards of earthquake, landslides and tsunamis to coastal nuclear power plants located along active strike-slip fault zones in California, and 2) an assessment of the eastern Aleutian-Alaska subduction zone to determine whether conditions exist along the megathrust that are similar to Japan, which could result in the generation of a giant earthquake and tsunami that would pose a thrust to ports and harbors along the West Coast. Results of these studies will available to and have a direct impact on the re-licensing of the nuclear facilities. The Aleutian-Alaska studies will also contribute significantly to the Multihazard Demonstration Project tsunami scenario and planned 2014 emergency management exercise.

Shaded relief bathymetry draped draped by slope gradient, warm colors indicate steep slope, cool colors indicate gentle slope.

Above, Shaded relief bathymetry draped draped by slope gradient (warm colors= steep; cool colors = gentle). Submarine headwall and sidewall scarps delineate several larges landslide evacuation zones and their associated deposits along the floor of Santa Cruz Basin. Slides face the mainland shoreline of Santa Monica and Redondo Beach. Read more on our News page.

Start/End Dates

10/1/2011 - 9/30/2016

Location

  1. Southern California Borderlands
  2. central and northern California
  3. Pacific Northwest
  4. Alaska
  5. Hawaii and Pacific Territories

Active Researchers

USGS Collaborators/Former Members

AK Eq Haz Map 2007

Map showing AUV-collected multibeam data (color scale) from a section of the La Jolla Canyon where the water depth ranges from 636 to 772 m. From: Paull, et al., 2013, Marine Geology v.335

Objectives

The USGS Coastal and Marine Geology program (CMGP) provides expertise to the nation in understanding hazards related to offshore earthquakes, landslides and tsunamis the U.S. and territorial coasts. As the recent 2011 Japan giant earthquake and tsunami have brought to light, there is still much we do not understand about conditions that lead to these unusually large events. All U.S. and territorial coastlines are vulnerable to both remote and remote hazards. This project focuses on regional geologic studies of active margins that are considered to be most at risk based on:

  1. the potential human and economic loss from earthquakes, landsides, and tsunamis,
  2. the lack of high resolution mapping and/or age dating in the area at risk, and
  3. the need for information to validate models and provide input into the hazards probabilistic studies project.

These field studies are an integral part of a coordinated CMGP effort to understand hazards and to develop scientifically sound contributions to forecasts of loss of life, infrastructure, and property from catastrophic geologic events associated with coastal and marine geologic processes.

As the population continues to migrate toward the coastlines, the societal impacts of these hazards are expected to grow. Recent giant earthquakes that spawned pan-oceanic tsunamis have revealed the vulnerability of U. S. coasts to such natural disasters. The highest priorities for regional active margin field studies are in direct response to the aftermath of the 2011 Japan 9.0 earthquake and tsunami:

  1. a re-assessment of the hazards of earthquake, landslides and tsunamis to coastal nuclear power plants located along active strike-slip fault zones in California, and
  2. an assessment of the eastern Aleutian-Alaska subduction zone to determine whether conditions exist along the megathrust that are similar to Japan, which could result in the generation of a giant earthquake and tsunami that would pose a thrust to ports and harbors along the West Coast.

Results of these studies will available to and have a direct impact on the re-licensing of the nuclear facilities. The Aleutian-Alaska studies will also contribute significantly to the Multihazard Demonstration Project tsunami scenario and planned 2014 emergency management exercise.

Approach

Thumbnail image from USGS SIM 3225, Hueneme Canyon Bathymetry.

Colored Shaded-Relief Bathymetry, Hueneme Canyon and Vicinity, California. From: Johnson et al., USGS Scientific Investigations Map 3225, Sheet 1

The strategy for this project is to focus resources on specific geographic areas that are considered by consensus to be the most at risk for earthquakes, landslides or tsunamis. This approach allows flexibility to refocus efforts in response to actual catastrophic events, or needs for model validation or the development of specific hazard assessment products. The project is separated into 5 tasks based primarily on geography and differing tectonic regimes:

  1. southern California Borderlands,
  2. central and northern California,
  3. Pacific Northwest,
  4. Alaska, and
  5. Hawaii and Pacific Territories.

Tasks and SubTasks

Cooperators

Products

Figure 2 from Johnson and Watt, 2012, Geosphere volume 8

Map showing regional geography, locations of seismic-reflection profiles (faint blue lines), outer boundary of multibeam bathymetric mapping (yellow line), significant faults (thick black lines), fault sections (A through H), and locations of the more detailed maps. From: Johnson and Watt, 2012, Geosphere v.8

Hartwell, S.R., Finlayson, D.P., Dartnell, P., and Johnson, S.Y., 2013, Bathymetry and Acoustic Backscatter—Estero Bay, California: U.S. Geological Survey Open-File Report 2013–1225, doi: 10.3133/ofr20131225

Johnson, S.Y., Dartnell, P., Cochrane, G.R., Golden, N.E., Phillips, E.L., Ritchie, A.C., Kvitek, R.G., Greene, H.G., Endris, C.A., Seitz, G.G., Sliter, R.W., Erdey, M.D., Wong, F.L., Gutierrez, C.I., Krigsman, L.M., Draut, A.E., and Hart, P.E. (S.Y. Johnson and S.A. Cochran, eds.), 2013, California State Waters Map Series—Offshore of Carpinteria, California: U.S. Geological Survey Scientific Investigations Map 3261, pamphlet 42 p., 10 sheets, scale 1:24,000

Johnson, S.Y., Dartnell, P., Cochrane, G.R., Golden, N.E., Phillips, E.L., Ritchie, A.C., Kvitek, R.G., Greene, H.G., Krigsman, L.M., Endris, C.A., Clahan, K.B., Sliter, R.W., Wong, F.L., Yoklavich, M.M., and Normark, W.R. (S.Y. Johnson, ed.), 2012, California State Waters Map Series--Hueneme Canyon and vicinity, California: U.S. Geological Survey Scientific Investigations Map 3225, 41 p., 12 sheets, and GIS data

Johnson, S.Y., Dartnell, P., Cochrane, G.R., Golden, N.E., Phillips, E.L., Ritchie, A.C., Kvitek, R.G., Greene, H.G., Krigsman, L.M., Endris, C.A., Seitz, G.G., Gutierrez, C.I., Sliter, R.W., Erdey, M.D., Wong, F.L., Yoklavich, M.M., Draut, A.E., and Hart, P.E. (S.Y. Johnson and S.A. Cochran, eds.), 2013, California State Waters Map Series—Offshore of Ventura, California: U.S. Geological Survey Scientific Investigations Map 3254, pamphlet 42 p., 11 sheets

Johnson, S.Y., and Watt, J.T., 2012, Influence of fault trend, bends, and convergence on shallow structure and geomorphology of the Hosgri strike-slip fault, offshore Central California: Geosphere, v. 8, no. 6, 25 p., doi: 10.1130/GES00830.1

Langenheim, V.E., Watt, J.T., and Denton, K.M., 2012, Magnetic map of the Irish Hills and surrounding areas, San Luis Obispo County, central California: U.S. Geological Survey Open-File Report 2012-1080, scale 1:24,000

Paull, C.K., Caress, D.W., Lundsten, E., Gwiazda, R., Anderson, K., McGann, M., Conrad, J.E., Edwards, B.D., and Sumner, E.J., 2013, Anatomy of the La Jolla Submarine Canyon system: offshore southern California: Marine Geology, v. 335, p. 16-34, doi: 10.1016/j.margeo.2012.10.003

Ryan H. F., R. von Huene, , D. W. Scholl, and S. Kirby, 2012, Tsunami hazards to U. S. coasts from giant earthquakes in Alaska, Eos, v. 93, n. 19, p. 185-186

Ryan, H.F., Conrad, J.E., Paull, C.K., and McGann, M., 2012, Slip rate on the San Diego Trough fault zone, inner California Borderland, and the 1986 Oceanside earthquake swarm revisited: Bulletin of the Seismological Society of America, v. 102, n. 6, p. 2300-2312, doi: 10.1785/0120110317, download PDF, 2.7 MB

Sliter, R. Johnson, S.Y., Watt, J.T., Scheirer, D.S., Allwardt, P. and Triezenberg, P.J., 2013, High-resolution seismic-reflection and marine-magnetic data from offshore central California--San Gregorio to Point Sur: U.S. Geological Survey Open-File Report 2013-1071

 

Accessibility FOIA Privacy Policies and Notices

USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://walrus.wr.usgs.gov/research/projects/eq_tsu_land_cathaz.html
Page Contact Information: Laura Zink Torresan
Page Last Modified: 5 December 2014 (lzt)