Ch. 8 - HW (Tsunami Versus Wind-Caused Waves)

Tsunami wavelengths can be as great as _________.

780 km

Most tsunami travel at speeds of _________ miles per hour.

420 to 480

Tsunami arrive as a series of several waves separated by periods typically in the _________ range.

10- to 60-minute

Tsunami are typically about _________ high in the open ocean, and 6 to 15 m high on reaching shallow water.

1 m

In 1868, the USS Wateree was carried several miles inland by a tsunami along the coast of ______.

Chile

The 1946 April Fool's Day tsunami at Hilo, Hawaii, was caused by an earthquake near ________.

alaska

The great 1960 Chile earthquake (M 9.5) unleashed a tsunami that killed over 1,000 Chileans. These waves also killed 61 people in Hilo, Hawaii, 14 hours after the earthquake, and another 185 people in ________, 22.5 hours after the earthquake.

Japan

The great 1964 Alaska earthquake (M 9.2) set off a tsunami that killed 122 people along the state's sparsely populated coastline. This tsunami also killed 12 people in the state of _________.

california

In 1964, 12 people were killed during a tsunami at Crescent City, California. All of these fatalities were caused by the _______ wave, which was the highest in the series.

fifth

The 1964 tsunami that killed 12 people at Crescent City, California, was caused by a major earthquake in _________.

alaska

The 2004 _________ Ocean tsunami killed an estimated 245,000 people in 13 countries.

indian

The trees that died in the Pacific Northwest after the great earthquake of 1700 were killed by __________.

seawater after faulting dropped the land below sea level

Detailed mapping of the ocean bottom around the Hawaiian Islands revealed a previously unrecognized tsunami source. What did geologists discover on the seafloor in this area?

slumps and debris avalanches formed by volcanic flank collapse

Geologists have shown that the east coast of the United States faces a serious tsunami threat from ________.

volcanic flank collapse in the Canary Islands

The deadly 1998 tsunami in Papua New Guinea was caused by ________.

an undersea landslide triggered by an earthquake

The largest historic tsunami wave run-up ever recorded was caused by a massive rockfall into the water at ________________.

Lituya Bay, Alaska

A _________ is an oscillating wave that sloshes back and forth within an enclosed body of water such as a sea, bay, lake, or swimming pool.

seiche

In 1959, the water stored behind Hegben Lake Dam in Montana began to slosh violently back and forth in a series of oscillating waves. These seiches were caused by __________________.

a sudden drop of the lake bottom during an earthquake

Modern tsunami warning systems primarily use __________.

DART II stationsand reports from Coast Guard ships

Tsunami events at a coastline __________.

can start with a drawdown or rising of the sea

The theoretical velocity of a tsunami in the deep ocean is calculated by taking the square root of the product of __________.

the acceleration due to gravity and the depth of the ocean

Most of the 245,000 deaths from the 2004 Indian Ocean tsunami occurred in _______.

Indonesia

Which of the following statements is about tsunami in the deep ocean?

They are always "feeling" the bottom.

Multiplying 1.25 by the square root of the wavelength results in the velocity of a __________.

wind-blown wave in deep water

Tsunami that reach the shallow water slow down due to __________.

friction with the bottom and internal turbulence

Which of the following statements is true regarding tsunami and volcanoes?

Volcanic eruptions can result in tsunami as they explode, collapse, or send debris into the water.

The best course of action to take if you suspect a tsunami is headed your way is to __________.

head to higher ground and stay there

The Japanese Tsunami inflicted destruction along the coast and in Sendai, the wave travelled inland __________.

10 km

Regarding the Fukushima Daiichi nuclear disaster, the Tokyo Electric Power Company (TEPCO) hopes that they will be able to remove the melted nuclear fuel masses in __________.

30-40 years

The 2004 Indian Ocean tsunami was caused by Earth's third-most powerful earthquake in the last 100 years.

true

The English language term tidal wave is a good description of a tsunami because of their relationship to ocean tides.

false

The destructive power of a tsunami is due mostly to the great height of the wave.

false

The 2004 Indian Ocean tsunami was generated by a magnitude 9.2 earthquake along __________ off the shore of Sumatra.

a subduction zone

Tsunami have long wavelengths and very short wave heights in the open ocean.

true

It is virtually impossible for small ships at sea to survive a passing tsunami.

false

While California has experienced many deadly earthquakes, it has never experienced fatalities from tsunami.

false

People living around Lake Tahoe have to worry about seiches but not tsunami.

false

It is possible that a large hunk of Hawaii could be plunged into the sea following a large earthquake, generating a powerful tsunami.

true

There is little threat of a tsunami striking the East Coast of the United States.

false

There is little threat of a tsunami striking the crowded beaches of Southern California.

false

The sloshing of a swimming pool during an earthquake is called a seiche.

true

People always feel the distant earthquakes that form the tsunami that hit their local coastline.

false

Removing coral reefs is a good way to reduce the damage caused by tsunami.

false

Prior to the 2004 event, the last major 1883 tsunami in the Indian Ocean struck in 1883 and killed about 36,000 people. This tsunami was caused by _________________.

the collapse of Indonesia's Krakatoa Volcano

During the Japanese Tsunami, the seafloor was thrust up 5 m to 8 m (16 feet to 26 feet).

true

Most of the deaths associated with Japanese Tsunami were caused by earthquake collapsed buildings.

false

In 2011, after the nuclear plant destruction, evacuation orders were given to 150,000 residents living within 20 km (12.4 mi) of the failed plant.

false

In 1958, Lituya Bay (AK) witnessed a tsunami resulting from a rockfall of approximately 9 million tons of debris falling 90 meters into the bay.

false

Tsunami is a Japanese word that means __________ waves.

harbor

Tsunami are created by big "splashes" made in the deep ocean by all but which of the following?

hurricanes

Earthquake-related tsunami are created by sub sea fault movements with pronounced vertical offsets of the seafloor. Such movements occur most commonly along __________________.

subduction zones

Tsunami typically have _________ relative to wind-blown waves.

long periods and long wavelengths

The captain of a ship tells you that he once experienced a huge tsunami while sailing in the Pacific Ocean several hundred miles from any landmass. You decide that this sounds a little far-fetched because _________.

tsunami are rarely felt in deep water because they have long wavelengths and low heights