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17

Tsunamis and sound waves are different types of wave - one is a transverse wave and the other is a longitudinal one. Let's look at the factors that influence the speed of each one is determined. Tsunami - transverse wave in shallow water A transverse wave is one of the type that we think of from day to day - where the direction of oscillation is ...


11

It has nothing to do with the geological cause of the tsunami. Instead, it's a result of the way waves propagate. You can see the same effect on ordinary wind-generated ocean waves — the waterline draws back before each wave peak arrives and washes up the beach. Tsunamis are much bigger waves, in terms of both amplitude and wavelength, so the effect is more ...


10

As a lecturer I had during my undergraduate put it: if you draw your information from BBC/Discovery Channel documentaries, you will believe we could get a 100-million-people-killing disaster every week. The collapse of the Cumbre Vieja is but one of those perceived threats. How do such documentaries get their info? Scientists develop models, then run them....


10

The answer to some parts of your question lie mainly in basic physics, there are a number of factors that will affect how a Tsunami will travel after the initial water displacement. For example, is the initial displacement a point event (such as Tsunami caused by landslides), or an event occurring along a long line, such as the massive fault movement that ...


10

The linked paper does numerical modelling of a hypothetical tsunami and predicts speeds between 60 m/s (at its point of origin) and 30 m/s (nearer to shore). We can try a back-of-an-envelope approximation to see if we get close, and to understand why the speed would be so much lower than on Earth. A tsunami behaves as a gravity wave with a very long ...


8

This is the centroid moment tensor published by the USGS as of 01/10/18 (it will likely be updated in the future). As you can see this was an almost pure strike-slip mechanism on a near vertical plane. Tsunamis are generated when the ocean floor is displaced upwards by an earthquake, displacing the water above it in the same pattern. This displaced water ...


7

Short answer: Tsunami models use the shallow-wave mathematical approach, because their wavelength is usually much larger than the relevant water depth determining their propagation. Long answer: Tsunamis are often called 'tidal waves' to highlight the idea that their characteristic time response is closer to tydes than to the standard wind waves we are used ...


7

An asteroid impact in the ocean is an oversized example of throwing a pebble in a pond - both will produce waves in a concentric pattern from the point of impact. The height of the waves and the energy they would have would depend on the amount of energy the asteroid transferred to the water at the impact sight. The energy transferred will depend on the ...


7

The answer to your question, based on linear theory, is no. The short answer is that the slope of these waves is very small, and the displacement of the particle paths is proportional to (ak) (times, perhaps, a depth dependent term) with a the wave amplitude and k its wavenumber. Now let's make this answer rigorous. Recall, for irrotational inviscid 2 ...


6

Your question seems to lump at least three different phenomena together: tsunami waves(seismic sea waves), the effects of landslides near the coast, and the effects of asteroid impact into the ocean. You might have also included rogue waves. Each of these are complex phenomena when you start considering 'realistic' boundary and initial conditions - so you ...


6

Scandinavia experienced a lot of earthquakes due to post glacioisostatic rebound 10 - 7 ka. The most likely trigger for the Storegga Slide was a strong earthquake or a series of earthquakes. However, large sediment input from glaciation rather than earthquakes are the causes of the unstable slope. Release of overpressured gas hydrates was the driving force ...


6

If I remember correctly from my intro to paleo class, the terms articulate and inarticulate refer to a classification of brachiopods depending on the nature of their hinge. Articulate brachiopods have something like interlocking hinges (like a door hinge) made from serrated (or tooth like) parts of the shell. On the other hand, inarticulate brachiopods hold ...


4

I can't answer part a, but I can help with part b. We first must determine how much kinetic energy, then we can use simple thermodynamics to see how much that could possibly heat up a mass of water. Kinetic energy calculations are numerically modeled in Dutykh and Dias, 2009. Their largest example uses parameters of a 150km x 50km x 35km fault slipping by ...


3

Tsunamis are created when large volumes of water are displaced vertically. The predominant ways this can happen are when an earthquake of significant magnitude is created at a subduction zone - one tectonic plate subducting under another tectonic plate. During such an event, part of one plate moves downwards or upwards very quickly causing the water above ...


3

The ability to predict depends on the cause of the tsunami. Earthquakes can't be predicted, so a tsunami caused by an earthquake can't be predicted. A meteor can be tracked for a considerable time in space before sticking earth so a tsunami caused by an meteor strike can be predicted. There is also the possibility of a tsunami early warning system. There ...


2

The height will be limited by the maximum height of the rim wall. For a Chicxulub like scenario the rim wall will be at least a km high. The initial impact will off course cause some water to evaporate, some will be ejected many kilometers into the atmosphere (e.g., during the 'splash') but for the sake of this question I am discarding transient deformation ...


2

Tohoku is the seismogenic zone, the asperity model explained this small repeating earthquake well. It was said massive earthquake will occur in Nankai Trough. As their expectation was wrong, [Kato and Yoshida, 2011],[Hori and Miyazaki, 2011] created new models. ref Notice japanese source. Here is new model of Sansoken(National institute of advanced ...


2

A quote from the summary of the book you listed: feeding torrents of freshwater into ocean basins that rapidly filled to present levels. The removal of the enormous weight of ice at high latitudes caused the crust to bounce back triggering earthquakes in Europe and North America and provoking an unprecedented volcanic outburst in Iceland. A giant ...


2

The reason why there was no large tsunami is due to the reason above, no significant uplift of the sea floor. However, a small tsunami was produced. This was due to vertical features such as trenches and seamounts (basically, undulating bathymetry) moving laterally, in a strike-slip earthquake acting as paddles within the overlying water column. They ...


1

What causes Tsunamis is the energy released, not so much the water displaced. The energy travels through the water passing from molecule to molecule of water. Amazing stuff. There is a vertical 'stem' of energy. Out in the deep ocean one will not be able to even see an abnormal 'wave'. Once that energy stem encounters a shallow bottom, that is when ...


1

How likely is that the next big earthquake (and tsunami) will hit the Philippines again? The likelihood is 100%, but we don't know when. It could be tomorrow, it could be in a year, or it could be in 100 years. Make sure you are prepared for such an event. The Philippines are situated above a subduction zone (the Philippine trench), so an earthquake is ...


1

Remember that a wave when it passes moves every particle up and down (with no horizontal component) so in deep water tsunamis have very little affect on anything. In addition, the wavelength/amplitude of these waves is huge so the water rises very gently and it is hardly noticed in deep water. In fact, the safest place to be when a tsunami is coming (beside ...


1

The bolide depicted in the film seems to have been modeled upon the Chixculub meteor that impacted Yukatan, and created the K-T extinction event. Both the film and Chixculub were about 11 kilometers in diameter. This would result in a roughly $10^5$ Gtonne impact explosion - with some variation depending upon the density of the bolide, and the orientation ...


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