Paleotsunami Inundation of a Beach Ridge Plain: Cobble Ridge Overtopping and Interridge Valley Flooding in Seaside, Oregon, USA

Table 2

Central Cascadia subsidence and paleotsunami events for the last ∼2,500 years.

Event number	Regional subsidence	Seaside subsidence core site record	Regional tsunami	Seaside tsunami core site record	Event age
Historic	None	na	Farfield	j14	1964 AD
#1	Large	NW2	Nearfield	NW2, NW7	AD 1700
#2a	None	na	Source?	NW2	~0.8 ka
#2b	Medium	NW2	Nearfield	NW2, NW7	~1.1 ka
#3	Small	—	Nearfield	NM2, j40b	~1.3 ka
#4	Large	NW2	Nearfield	NW2	~1.7 ka
#5	Medium	—	Nearfield	j40b	~2.6 ka

Coseismic subsidence from event #1 at AD 1700 is estimated to be 1.0±0.5 m in Seaside [16].
Regional central Cascadia data from [8].
Regional subsidence event dates [26].
Overland paleotsunami events [7, 27].
Seaside core site references: NW2, NW7 [2]; j14, j40b [6].
Seaside core sites are shown in Figure 2, except for site j14, which is shown later in Figure 11.
Seaside core logs and radiocarbon ages are shown in Figure 3, except for j14, which is shown later in Figure 10.