5) Tsunami can take several hours to cross the ocean because
A) they move slowly
B) they are so high that wind impedes their progress
C) the travel distances are great
D) the ocean is too deep to transmit the waves
6) The 1700 AD tsunami generated by a large earthquake on the Cascadia subduction zone in the
Pacific Northwest was dated most precisely using
A) Native American histories
B) Pacific Northwest sediments
C) Japanese tsunami records
D) early seismograms in China
7) The first step in producing a timely warning of a tsunami is
A) detection of a possible tsunami-producing earthquake
B) detection of a tsunami using a tsunameter
C) closely watching tidal gauges
D) calculation of ocean travel times
8) Tsunamis can be detected on the open ocean through
A) measurement of changes in pressure exerted on the sea bottom by the water column
B) shipboard observations of wave heights
C) seismometer records
D) measurement of wave speeds with Doppler radar