Very large wave created by a large, sudden displacement of material into a body of water
Diagram of the 1958 Lituya Bay megatsunami, which proved the existence of megatsunamis
A megatsunami is a very large wave created by a large, sudden displacement of material into a body of water.
Megatsunamis have different features from ordinary tsunamis. Ordinary tsunamis are caused by underwater tectonic activity (movement of the earth's plates) and therefore occur along plate boundaries and as a result of earthquakes and the subsequent rise or fall in the sea floor that displaces a volume of water. Ordinary tsunamis exhibit shallow waves in the deep waters of the open ocean that increase dramatically in height upon approaching land to a maximum run-up height of around 30 metres (100 ft) in the cases of the most powerful earthquakes.[1] By contrast, megatsunamis occur when a large amount of material suddenly falls into water or anywhere near water (such as via a landslide, meteor impact, or volcanic eruption). They can have extremely large initial wave heights in the hundreds of metres, far beyond the height of any ordinary tsunami. These giant wave heights occur because the water is "splashed" upwards and outwards by the displacement.
Examples of modern megatsunamis include the one associated with the 1883 eruption of Krakatoa (volcanic eruption), the 1958 Lituya Bay megatsunami (a landslide which caused an initial wave of 524 metres (1,719 ft)), and the Vajont Dam landslide (caused by human activity destabilizing sides of valley). Prehistoric examples include the Storegga Slide (landslide), and the Chicxulub, Chesapeake Bay, and Eltanin meteor impacts.
^"Tsunami Characteristics". Pacific Tsunami Museum. Retrieved 26 July 2021.
A megatsunami is a very large wave created by a large, sudden displacement of material into a body of water. Megatsunamis have different features from...
kilometers (50 mi) away, and the sudden displacement of water resulted in a megatsunami that washed out trees to a maximum elevation of 524 meters (1,719 feet)...
Works. On 9 October 1963, during initial filling, a landslide caused a megatsunami in the lake in which 50,000,000 m3 (1.8×109 cu ft) of water overtopped...
eyewitness report of the existence of megatsunamis. Wikimedia Commons has media related to Lituya Bay megatsunami. Lituya Mountain Guinness World Records...
Madagascar. Based on a hypothesis that these dunes were formed by a megatsunami resulting from an impact, the researchers were able to triangulate the...
modern technology and scientific research. One of the largest was a megatsunami resulting from the asteroid that wiped out the dinosaurs. Studying paleotsunamis...
once reached a height of 330 ft (100 m), classing this tsunami as a megatsunami. At the Osaki-bana point Futsu town, the waves locally grew to a height...
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slide into the ocean. This could then generate a giant wave, known as a "megatsunami" around 650–900 m (2,130–2,950 ft) high. The wave could radiate out across...
count as a megatsunami, with the highest prediction for Western Sahara comparable to the Japanese tsunami, so it would only be a megatsunami locally in...
Lituya Bay megatsunami, which had a record height of 524 m (1,719 ft). The only other recent megatsunamis are the 1963 Vajont Dam megatsunami, which had...
water after filling the crater, and related seismic activity spawned megatsunamis over 100 meters (330 ft) tall, with one simulation suggesting the immediate...
light as Redmond dies. On television, news reports show devastating megatsunamis. Andrew believes Redmond is Rory O'Bannon, a man who had been arrested...
The 1883 eruption of Krakatoa (Indonesian: Letusan Krakatau 1883) in the Sunda Strait occurred from 20 May until 21 October 1883, peaking in the late morning...
boundaries. A volcanic collapse in Lanai 100,000 years ago generated a megatsunami that inundated land at elevations higher than 300 metres (980 ft). Tourism...
several towns. Around 2,000 people died. Scientists named these waves megatsunamis. Some geologists claim that large landslides from volcanic islands, e...
history. Such an event would've caused global volcanism, earthquakes, megatsunamis, and global climate change. >2.4×1010 >28 ZWh The impact energy of Archean...
Molokaʻi experienced a 75 m (246 ft) tsunami, and 100,000 years ago a megatsunami 325 m (1,066 ft) high struck Lānaʻi. A more recent example of the risks...
with the band name; naming it after the 1958 Lituya Bay earthquake and megatsunami that swallowed one of Alaska’s gulfs. Oceans Ate Alaska was founded in...
the sea, can generate tsunamis. Massive landslides can also generate megatsunamis, which are usually hundreds of meters high. In 1958, one such tsunami...
hypothesized as providing evidence of "megatsunamis" caused by comets or asteroids crashing into Earth. However, the megatsunami origin of the Fernambosy and other...
190 km (120 mi) into the sea, and generated a 600 m (2,000 ft)-high megatsunami that inundated the rest of Molokai and severely damaged the surrounding...
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