Oceans often get oil and toxic waste dumped into them as a bit of a "cheat" to cheaply dispose of waste. This harms the ocean life greatly. A leading cause of dumping into the oceans is the expense of getting rid of used oil. If a city were to allow residents to dispose of these things at no cost to them, there would be no need for people to dump it into the ocean. This will reduce the harm to sea life.
Ground Shaking. If an earthquake generates a large enough shaking intensity, structures like buildings, bridges and dams can be severley damaged, and cliffs and sloping ground destabilised. ... Tsunami.Landslides and Rockfalls.Subsidence and Lateral Spreading.Liquefaction