Historical clue formulations

• Seismologist's concern — 2022-04-28
• Overwhelming amount — 2021-11-30
• Coastal hazard — 2015-10-02
• Seaquake sequel — 2011-05-26
• Literally, "harbor wave" — 2005-02-01
• Salt shaker? — 2002-01-01
• Wave of destruction — 1999-12-21
• Result of submarine activity — 1999-02-19