2: Coastal Processes

Question 1

Tsunami wave causes

Answer 1

Large undersea earthquake
Landslide (from seismic or volcanic activity)
Meteorite impacts

Question 2

Example: Indian Ocean

Answer 2

Generated by M 9.1 earthquake on a subduction zone

Question 3

Example: Japan (2011)

Answer 3

Generated by M 8.9 earthquake on a subduction zone

Question 4

Lituya Bay, Alaska

Answer 4

Evidence of a giant wave in 1936

Another giant wave occurred in 1958 triggered by a landslide from M 8.0 earthquake

Question 5

Potential Threat: La Palma, Canary Islands

Answer 5

Stratovolcano (Cumbre Vieja)
North-south rift (fracture) zone dotted with cinder cones
1949 eruption - western half of island slipped ~ 2 meters along this fracture
Future Eruption - some potential for total collapse of western half of island

Question 6

What would happen if a future eruption collapsed the Canary Western Island?

Answer 6

If this happens, a megatsunami may occur and send a 200-300 foot wave into coastal areas surrounding the Atlantic (East Coast of USA)

Question 7

Cascadia subduction zone, Pacific NW

Answer 7

geologic past and potential threat