Questions tagged [earthquakes]
Questions regarding a sudden release of seismic waves into the Earth's crust. As well as the causes of earthquakes, their consequences and physics.
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What criteria determines whether earthquakes are classified as new or aftershocks?
I saw a recent paper where it is claimed that aftershocks can occur years, decades or centuries after the main earthquake.
When seismic activity is observed, what criteria determines the ...
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What's the strongest earthquake we currently can miss observing on Earth?
Reading jeffronicus' answer about how seismic stations record bomb explosions, particularly the reminder that the intensity of earthquakes drops by distance, made me start wondering what scale of ...
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Are seismometers over the world "feeling" the small earthquakes caused by air raids and shelling on Gaza Strip?
When watching news about earthquakes, I think most people are used to hear about the Richter scale, a logarithmic scale used to measure earthquake intensity. A very strong earthquake, like the 2011 ...
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Could humans cause an earthquake?
I saw something that mentioned how, during the 2018 World Cup, after a victory, thousand of fans jumping simultaneously caused seismologists to detect the equivalent energy release of a magnitude 2.0 ...
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What is the maximum intensity with which an earthquake can struck Chitral city in Northern Pakistan?
I am working on a disaster response logistics case study in which I am using Mi-17 helicopters for transportation of relief to the affected areas in main Chitral city.
In this regard, I want to ...
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How to model the travel time of tsunami waves generated by volcanic explosion?
I am trying to understand how can I model the travel time of tsunami waves generated by volcanic explosions? I want to analyze the 2022 Tonga tsunami. I have been using the UNESCO CoMIT software with ...
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Did the 1990 Manjil-Rudbar earthquake postpone a massive earthquake in Tehran?
In this site (published on 6 November 2001) I found the following information:
Historical data suggest there is a major earthquake in Tehran every 158 years and the last one there was in 1830.
The ...
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When rock cracks at tectonic plate boundaries are the number and size of cracks reflected in seismographs?
Do seismographs become more complex (waves of different frequencies superimposed on one another) for higher magnitude earthquakes where I am guessing there would be a larger variety and number of ...
user28909
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How many people will lose their lives if a big earthquake shakes Bucharest?
Bucharest becomes a huge city. Bucharest has never seen such dense population before. from 1947 to 1990 there was a communist government in Romania. 1988 Armenia earthquake with 38,000 deaths shows us ...
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What is the relationship between earthquake risk, magnitude, and distance from the epicenter?
I need a (rough) functional relationship between these three quantities. My initial hypothesis is that the risk $R$ (intended as the probability of a building damage), scales with the square root of ...
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How to add more outdoor weather sensors to Software Defined Radio (Weather Station)
How to add more outdoor weather sensors to Software Defined Radio (Weather Station) ?
I am looking for seismographic outdoor radio sensors to work for Software Defined Radio (Weather Station).
So ...
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Where could I get waveform data on low-frequency earthquakes, very low-frequency earthquakes, volcanic tremor and non-volcanic earthquakes?
I am a marine geology masters student and I am writing my thesis on slow earthquakes. I will include graphs of the most common types of earthquakes:
Low-frequency earthquakes
Very low-frequency ...
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How does the Richter earthquake scale translate to the amplitude of horizontal surface movement at the epicenter?
In layman's terms, how does the Richter earthquake scale translate to the amplitude of horizontal surface movement at the epicenter?
For example, given an earthquake of Richter magnitude 4, what is ...
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Which point of an earthquake wave is considered as the earthquake's time?
For example, Time for the 2023 Turkey–Syria earthquake is 2023-02-06 01:17:35
What time does this exactly represent, the start of earthquake's wave or pick of the wave or something else?
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Can the planetary alignment actually affect earthquakes? [duplicate]
We've been hearing a lot these past few days about planes alignments and how it would affect seismology. How scientifically true is that?
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Do planetary alignments affect Earth's seismic activity?
There is a widely circulated tweet by Frank Hoogerbeets where it seems he has predicted Turkey's earthquake a few days before. The tweet says:
Sooner or later there will be a ~M 7.5 #earthquake in ...
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Does the Moon affect earthquakes?
Does the Moon, through factors like its location (if it is at an apsis i.e closest point or furthest point in its orbit) or some changes in density, affect earthquakes on the Earth?
Earthquakes are a ...
user27902
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Is it possible for tsunamis to occur on deep water planets?
Assume a water planet with an ocean depth of about 200-500 km.
Would a very strong ground-quake happening at the very bottom of the planet's ocean floor be able to cause a large tsunami to rise up to ...
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How did they know that there was a "desert tsunami" in a Death Valley cave after a 7.6 magnitude earthquake near the southwest of Mexico?
Phys.org's story from September 23, 2022 entitled Mexico earthquake triggers 'desert tsunami' 1,500 miles away in Death Valley cave includes the following:
About five minutes after the 7.6 magnitude ...
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The longest interval between earthquake main shock & after shock
On August 21, 2022, the Western Australian town of Cadoux experienced a magnitude 4.4 earthquake. According to the report of the incident, that earthquake might be an aftershock of a magnitude 6.1 ...
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Earthquake impacting opening of sealed drainage pits
Can earthquake causing cracks in the ground impact opening of sealed drainage pits in the ground?
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Is there a seismic discontinuity between the lithosphere and asthenosphere?
I've been learning about seismic discontinuities, mainly the 5 defined ones - Conorod discontinuity, Mohorovicic discontinuity, Repetti discontinuity, Gutenberg discontinuity, and Lehmann ...
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Igneous and Sedimentary Rocks' Susceptibility to landslide
Which is more susceptible to landslide based on lithology compared to one another?
Granite, Conglomerate, Sandstone, Mudstone
I've been tasked to create a hazard map and was given a Geologic Map, ...
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If the Bennu asteroid were to hit within a 500 mile radius of Yellowstone National Park, will it trigger a super volcano at Yellowstone?
I am curious to know if it would be highly probable that if the Bennu asteroid were to hit the Earth in 2182, and the point of impact is within a 500 mile radius of Yellowstone National Park, will it ...
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Is There a Correlation Between Earthquake Magnitude and the Deformation Observed in the Rock?
I've been doing a little geology research. One of the topics that I noticed was the existence of "deformations" that appear in the rock layers if an earthquake has occurred. Smaller ...
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How much would the ground be displaced in a magnitude 11 earthquake?
In a magnitude 5 earthquake, the ground shakes violently and it's often impossible to stay upright. This is caused by about 50-120 cm of displacement of the ground. But how much would the ground move ...
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What Magnitude does it Feel Like when Far Away in an Earthquake?
I can't find a good way to say this but, if I had some info about an earthquake (i.e. magnitude 8, originating in water) and if I had a distance (i.e. 850 miles/ 1370 km) could I calculate what it ...
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Difference between Earthquake Seismographs
How can we tell the difference between a seismograph of a local earthquake and that of a distant earthquake?
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Farallon plate subducting under North American plate: is it a factor in "the next big one"?
I am a writer, not a scientist of any kind. I live in the SW AZ desert (USA), so we get earthquakes from time to time. I grew up in southern CA, right next to the San Andreas fault, so I have a ...
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Recent high seismic activity in Europe
It seems that Europe and the Mediterranean Sea have had high seismic activity in last six months. Major events which I remember are:
2020 Aegean Sea earthquake, magnitude of 7.0 Mww
29 December 2020:...
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What is this long mark undersea
Visiting Google Maps, I came across this long, sinuous, while pretty regular mark undersea that looks like an ancient river, when the sea was way lower, or a big (big!) boulder that could have rolled ...
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Is there any information on the height of waves near New Zealand resulting from today's M 8.1 Kermadec Islands earthquake?
The video in this tweet shows the small wave produced at Tokomaru Bay in New Zealand following the M 8.1 - Kermadec Islands, New Zealand 2021-03-04 19:28:31 (UTC) event. These are so far the only ...
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Is an Earthquake Large Enough to Cripple the Entire West Coast of North America Possible?
I have an idea for a novel I want to turn into a reality, and I'm starting some research first to make my book at least plausible in very specific conditions. The main aspect of the story would be ...
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Is it possible for Mexico to have a magnitude 9 earthquake?
Everyone has heard of the Cascadia Subduction Zone and the potential threat it poses. However, I have heard nothing about The Cocos Subduction Zone, even though it caused a devastating earthquake over ...
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How much time is there between an underwater earthquake and the moment a tsunami hits the coast?
Tsunamis can be caused by underwater earthquakes, like the 2004 tsunami in the Indian Ocean. The precise value will likely depend on where the earthquake is relative to the coast. But what is the time ...
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Seismic activity in the UK [duplicate]
On 8th September 2020 there was a magnitude 3.9 earthquake here in the UK at 51.817°N 0.665°W which is approx. 10km/6.2miles east of Aylesbury or roughly 50km/31miles east of Oxford.
This got me ...
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OpenEEW - earthquake early warning by everyone?
This site
https://grillo.io/
and here
https://github.com/openeew/openeew/
advertises such a system. But from the make-up of the site and no geo-science related work that they link to (at least what I ...
user20217
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Could the 5.7 earthquake in Utah be a precursor to a larger one?
Trying to verify the validity of a rumor.
https://earthquake.usgs.gov/earthquakes/eventpage/uu60363602/executive
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How Can Adjacent Parts of an Oceanic Plate be Subducted in Different Directions?
It is claimed by some that the reason for gaps in chains of volcanoes generated by plate subduction is that some parts of the plate dive deep into the mantle and generate magma plumes, while other ...
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Locating an seismic epicenter
I understand how to find an epicenter using three sensor locations and why three locations are needed. Is it possible, though very improbable, to find an epicenter if you only have two seismic ...
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If a very huge Earthquake occured anywhere on Earth could waves emerge to come together again on the opposite side?
Suppose that a super-powerful earthquake occurred anywhere on Earth, say one with the value 10 on Richter's scale. The quake can have any value but as can be read in a comment below the highest value ...
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Could Rumblings From Plutons be as Ominous as Rumblings From Volcanoes?
Mount Kinabalu in North Borneo is a 10 million year old pluton. A pluton is a magma plume from the mantle which was not able to reach the surface and erupt as a volcano, but solidified underground and ...
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Could an earthquake on flat land still kill someone without any buildings/boulders or such near by?
Suppose you were sitting near the epicenter of an earthquake, sitting down on flat land without much else near by, maybe some grass. Is it still possible that say, a magnitude 8 or 9 earthquake would ...
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Is there a general equation to know how big of an area is affected by an earthquake?
If you visit USGS earthquakes listing, you get 3 points of information for each earthquake: Location, depth, magnitude. My question is, is there a way to approximate how big of an area is affected? ...
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Is it reasonable to approximate the swinging building (base of the building) during an earthquake to a simple harmonic motion?
I am thinking of making a model of swinging building during earthquake and study the methods to minimize the swinging.
So does it even makes sense to approximate the swinging buildings (the base of ...
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Would the shaking of an earthquake be visible to somebody in a low-flying aircraft?
If you are in an airplane well above ground level, but low enough to see the faces of people relatively easily, and an earthquake happens, will you see the ground shake?
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What is the lateral ground acceleration, at the fault line, during a strike-slip earthquake?
I've read that peak lateral ground acceleration for magnitude 7 - 8 earthquakes is ~1 g at the epicenter (is that correct?), but I'm wondering if it might be significantly higher right at the ...
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Is this series of earthquakes near Broome, Australia normal?
There have been a series of earthquakes (some strong) near Broom, Western Australia. See this screenshot of the Geoscience Australia earthquakes map:
I didn't believe there were any faults around ...
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Why is it hard to predict earthquakes?
An analogy I came up with is:
Predicting earthquake strength and timing is like throwing a sheet of glass on the ground and predicting how many pieces it will break to and where they'll end up.
Is ...
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What is the vertical axis of this waveform shown in this tweeted IRIS GIF?
This IRIS tweet shows a video of siesmic waves from the recent M6.4 Earthquake in California rolling across the US.
I've made a small GIF to give the idea but the "GIF" in the tweet shows the whole ...
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