Department of Natural Resources Geology Division put together a report on the Ledgewood Landslide on Whidbey Island. Fast action assessment. But exciting work. http://www.dnr.wa.gov/publications/ger_qr_whidbey_island_landslide_2013.pdf
Just a few points: 1) This is not a new landslide. All but a small part of the headwall scarp were within an area that had already had failed. It is just that this time a lot failed at once.
2) The deep-seated rotational component was impressive - the beach was uplifted 30 feet. It is not clear how much of that is from pure rotation and how much from the secondary translational part. 3) Now that so much of the slide area has been evacuated, the risk of future expansion of the slide complex is greatly increased.
Just a few points: 1) This is not a new landslide. All but a small part of the headwall scarp were within an area that had already had failed. It is just that this time a lot failed at once.
2) The deep-seated rotational component was impressive - the beach was uplifted 30 feet. It is not clear how much of that is from pure rotation and how much from the secondary translational part. 3) Now that so much of the slide area has been evacuated, the risk of future expansion of the slide complex is greatly increased.
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