1 / 12

Near-Field Tsunamis in the POLA and the POLB

Near-Field Tsunamis in the POLA and the POLB. Generated from Near-Shore Faults (M. Legg) Generated from Subaerial and Submarine Landslides (Synolakis, Borrero, Watts) Large scale near-shore slumps Failure of sediment in submarine canyons.

turi
Télécharger la présentation

Near-Field Tsunamis in the POLA and the POLB

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Near-Field Tsunamis in the POLA and the POLB • Generated from Near-Shore Faults (M. Legg) • Generated from Subaerial and Submarine Landslides (Synolakis, Borrero, Watts) • Large scale near-shore slumps • Failure of sediment in submarine canyons

  2. Local Tide Gage Records from the 1992 Cape Mendocino Earthquake and Tsunami

  3. Nearshore Canyons Along the California Coast as Potential Tsunami Sources

  4. Pt. Dume Submarine Canyon and Cross-Section of Sediment Deposits in Two California Canyons

  5. Waves Obtained in POLA/POLB from Numerical Model of Submarine Landslide (Slump) • (After Borrero, J.C. 2002)

  6. Some Laboratory Studies of Landslide Generated Waves

  7. A Laboratory Experiment of Offshore Waves Generated by Submarine Landslides Experiments conducted to investigate offshore generated waves from underwater landslides. Note: generally undeformed slide in the initial wave generating phase (after Watts, P.)

  8. Experiment of the Run-Up Generated by Subaerial and Submarine Solid Body Slides Shows a hemisphere (D = 3 ft) before release in a 300 ft long, 12 ft wide wave tank at Oregon State Univ. (after Raichlen, 2005)

  9. Experiment of the Run-Up Generated by Subaerial and Submarine Solid Body Slides Waves generated in an offshore direction by the hemisphere.

  10. Experiment of the Run-Up Generated by Subaerial and Submarine Solid Body Slides The “plume” in the lee of the hemisphere which generates the run-up.

  11. Some Final Thoughts for Southern California (POLA/POLB) • Tsunamis from far-field earthquakes in southern California lead to longer period oscillations compared to near-field events. This appears due to the excitation of the offshore waters and the extent of the shelf. • Forces on ships may depend on period content of excitation -- static vs. dynamic. • Velocities may be important in back channels (marina) • Local erosion problems may occur due to velocities. • Overtopping of wharfs and shoreward inundation. • Generation of debris and the impact of the waterborne debris on other structures.

More Related