What is the difference between a tsunami and a tidal wave?
Although both are sea waves, a tsunami and a tidal wave are two different and unrelated phenomena. A tidal wave is a shallow water wave caused by the gravitational interactions between the Sun, Moon, and Earth ("tidal wave" was used in earlier times to describe what we now call a tsunami.) A tsunami is an ocean wave triggered by large earthquakes that occur near or under the ocean, volcanic eruptions, submarine landslides, or by onshore landslides in which large volumes of debris fall into the water.
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New Tsunami Evidence Along One of Earth’s Largest Faults, the Alaska-Aleutian Megathrust
Recent geological studies of a key section of the Aleutian Island chain of Alaska suggest Aleutian tsunamis may occur more frequently than previously understood.
50-Year-Old Mystery Solved: Seafloor Mapping Reveals Cause of 1964 Tsunami that Destroyed Alaskan Village
Minutes after the 1964 magnitude-9.2 Great Alaska Earthquake began shaking, a series of tsunami waves swept through the village of Chenega in Prince William Sound, destroying all but two of the buildings and killing 23 of the 75 inhabitants.
Are American Cities Prepared For Massive Tsunamis?
Are American Cities Prepared For Massive Tsunamis?
Geologic Evidence of Past Tsunamis in California
An extensive sedimentary deposit formed by a tsunami in 1946 was recently discovered at Pillar Point Marsh near Half Moon Bay, California. While there were photos and eyewitness accounts of the tsunami and resulting damage at the time, finding the tangible evidence in the geologic record is an important part of assessing the long-term hazard of tsunamis on California coastal communities.
California Tsunami Would Have Costly Aftermath
The fearsome aftermath of a tsunami striking California might cost at least $3.4 billion to repair, but neither of the state's nuclear power plants would be damaged, suggests a new analysis that could help officials and the public prepare for a tsunami and reduce risks before any such disasters happen.
New Findings about Indian Ocean Tsunamis Offer Lessons for Pacific Northwest
The Indian Ocean tsunami that claimed a quarter million lives was not the first nor last of its kind, according to reports in the October 30 issue of the scientific journal Nature.
Science Used to Assess Earthquakes and Tsunamis Can Help Keep America Safe
Reston, VA – Learn how scientific assessment of earthquakes and tsunamis can reduce risk and the loss of life and property when natural hazards strike.
Preparing for Tsunami Hazards on Washington’s Pacific Coast
Preparing for Tsunami Hazards on Washington’s Pacific Coast
Animation of Tsunami Scenario in the Pacific Northwest
Animation of what a potential tsunami would look like generated from a large and hypothetical magnitude 9 subduction earthquake in the U.S. Pacific Northwest. The height of the tsunami waves is exaggerated compared to the land surface. Credit: Eric Geist, USGS
PubTalk 1/2017 — Unusual sources of tsunamis
A presentation on "Unusual Sources of Tsunamis From Krakatoa to Monterey Bay" by Eric Geist, USGS Research Geophysicist
- Not all tsunamis are generated by earthquakes.
- Tsunamis can be caused by volcanoes, landslides, and even atmospheric disturbances
- Data from tide gauges can help unravel the complex physics of these sources
Videographers:
Storm waves in Santa Cruz
Large storm waves crashing on the rocks near Santa Cruz, California
Aftermath of Southeast Asia Tsunami
Southeast Asia in May 2013. Tsunami brought in dangerous waves and destruction.
Large Breaking Wave on Beach
Photograph showing the impact of a large wave at the south shore of Laysan Island, with endangered Laysan teal in the foreground.
Location: Laysan Islands (Northwestern Hawaiian Islands).
PubTalk 12/2014 — Ten Years After the 2004 Indian Ocean Tsunami
How geology is reducing tsunami risk
by Bruce Jaffe, USGS Research Oceanographer
- Improvements in tsunamis warnings since the 2004 Indian Ocean devastation.
- Is California vulnerable to tsunamis?
- What is the geologic calling card of a tsunami?
- How does the geologic record foretell of future
Tsunamis: Tides have nothing to do with it
Tsunamis are devastating. Usually associated with earthquakes in the Pacific, these giant surges of oceanic water can kill thousands and do billions of dollars of damage in minutes. Surprisingly, most people in Oregon are not aware of the tsunami history and hazard along our very own coast. Listen in as we examine the science of tsunamis and sit down for a special
Nehalem town with tsunami evacuation sign
Tsunami evacuation sign in the town of Nehalem. OR.
Extensive damage in Japan after massive earthquake and tsunami
Extensive damage to buildings and roads, and large boats washed far ashore, provide valuable information to tsunami researchers. Here, in Natori, Japan, south of Sendai, the height of damage indicates that the water flow from the tsunami wave was about 10 meters (33 feet).