Talk:Earthquake/Archive 3

Semi-protected edit request on 4 October 2017
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 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format. Sparkling Pessimist   {{sup| Scream at me! }}  18:20, 4 October 2017 (UTC)

Intensity of earth quaking and magnitude of earthquakes
I am reverting to restore the section header to "Intensity of earth quaking and magnitude of earthquakes". While "earth quaking" may seem odd, that is the intent: to strikingly present a key point often overlooked, that earthquakes do not have intensity. Intensity is a measure of ground shaking – or quaking – which, though driven by an earthquake rupture, is also dependent on other factors such as ground conditions and distance from the rupture.

The human experience with "earthquakes" has been, and remains, primarily with the quaking of the earth. Only in modern times, when the source of such quaking was identified as ruptures in the earth's crust, has "earthquake" become more associated with the rupture event. As a quaking event the maximal intensity is certainly a key characteristic (as is also the extent of quaking, some times called the "felt-area") as experienced. However, this is separate from a rupture's energy, as measured by magnitude. And to judge by the apparent general confusion on this point, we would be remiss if we fail to clarify the point. ~ J. Johnson (JJ) (talk) 20:10, 22 November 2017 (UTC)

External links modified
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External links modified (January 2018)
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Asteroid induced earthquakes
Would the ground motion caused by an asteroid impact (e.g., Chicxulub) be considered an "earthquake"? I ask, because the Wikipedia article on Chicxulub Crater says "colossal shock waves would have triggered global earthquakes and volcanic eruptions.[28]" — Preceding unsigned comment added by Trasmuss (talk • contribs) 22:40 23 January 2018 (UTC)


 * Sure, why not? Such events are not tectonically caused, but when the earth quakes does it make much difference what the cause is? Just last week bolide burst over Michigan (?), which someone reported as causing a magnitude 2 quake.


 * BTW, when adding a comment please 1) add it to the bottom of the discussion (clicking on the "New section" tab will do that for you), and 2) sign it with the "four tildes" ( ~ ). ~ J. Johnson (JJ) (talk) 23:10, 23 January 2018 (UTC)


 * On the other hand!! I found https://sciencealert.com/january-2018-michigan-bolide-fireball-richter-scale-recording, quoting someone that: "The meteor did NOT cause an earthquake. It registered on the Richter scale as a measurment that would be equal to a 2.0 event." Which can lead back to the question of whether an earthquake is the quaking of the earth, whether it is magnitude 2 or magnitude 9, or a certain kind of event that causes the quaking. ~ J. Johnson (JJ) (talk) 04:10, 25 January 2018 (UTC)

I have just reverted with the edit summary "Added "asteroid impacts" per note on discussion page". What is this "per note"? Where have we discussed adding this very trivial item? You asked a question, and I referred that back to "the question of whether an earthquake" is the phenomena of the earth quaking, or the event that causes it. Regardless how that might be resolved, it seems to me that "asteroid impacts" are so rare as to be trivial, not warranting mention. ~ J. Johnson (JJ) (talk) 01:42, 30 January 2018 (UTC)

Not being a geophysicist, it seems like earthquakes are a phenomenom caused by multiple types of events. But in most of our risk analyses, catastrophic rare events may have a greater impact than the cumulative effects of smaller, mundane events. I don't think one can characterize a rare catestrophic event as trivial. Todd Rasmussen (UGA) 16:15, 11 February 2018 (UTC) — Preceding unsigned comment added by Trasmuss (talk • contribs)

Semi-protected edit request on 17 May 2018
In first section, second paragraph, change "earthquakes manifest themselves by shaking and sometimes displacement of the ground" to "earthquakes manifest themselves by shaking and sometimes displacing the ground" as a strictly grammatical correction. DavidPera (talk) 20:41, 17 May 2018 (UTC)
 * Yes check.svg Done Eggishorn (talk) (contrib) 22:04, 17 May 2018 (UTC)

Edit request
Under Earthquake Fault Types, third paragraph, "which may break in one go are approximately 1000 km." Not sure "one go" is proper nomenclature. --165.235.122.19 (talk • contribs) 16:32, 24 December 2014‎ (UTC)

A few typos 47.137.84.222 (talk) 21:48, 9 September 2018 (UTC)

A small edit
In the topic of , 48 of item, is 'global' instead 'gobal'.61.158.149.231 (talk) 16:19, 3 November 2018 (UTC)

Still me
's No.55, the year of this earthquake is 1964 instead 1946, the 1946 is in the Aleutian Islands. By the way, did I correct in type there?61.158.149.231 (talk) 16:39, 3 November 2018 (UTC)


 * Thanks for pointing those out, both fixed now. Mikenorton (talk) 18:11, 3 November 2018 (UTC)

Propagation Velocities can be much lower for soils.
In this article, propagation wave velocities are said to range from 3km/s to 12kM/s. I would say that this range is true for solid rock, but propagation velocities can go much lower. Shear wave velocities for very soft soils can go as low as about 100m/s. Even very stiff soils only get up to around 1kM/s to 1.5km/s. This is assuming that we’re talking about solid dynamics where v_s=(G/rho)^(1/2). I agree that deep bedrock propogation velocities are going to be 3km/s and up, but most soils won’t be this high, especially after it starts softening from cyclic strains caused by earthquake motions.

-Chris J Wong

(Structural Analysis Coder at Idaho National Lab) Crswong888 (talk) 09:24, 9 July 2019 (UTC)


 * Thanks Chris, I've reworked the text to add "solid rock" for the general statement and to include soils (and the rest of the upper crust) in the more detailed stuff lower down. I will look for a good citable source for my changes, but it's surprisingly difficult. Mikenorton (talk)


 * Bruce Bolt discussed P and S wave velocities in his excellent 1993 book, but off hand I don't recall if he mentions the different kinds of rock. I could check it tonight if you'd like. &diams; J. Johnson (JJ) (talk) 18:54, 25 July 2019 (UTC)


 * Thanks JJ, I was kind of hoping to find a single source that describes the P-wave velocity structure of the crust, including the shallow bit that most seismological papers/books ignore. I've found some nice specific examples, but nothing general. Mikenorton (talk) 20:16, 25 July 2019 (UTC)

"Lindol" listed at Redirects for discussion
An editor has asked for a discussion to address the redirect Lindol. Please participate in the redirect discussion if you wish to do so. Steel1943 (talk) 00:21, 22 January 2020 (UTC)

Semi-protected edit request on 23 July 2020
Please replace The Zipingpu Dam is believed to have fluctuated the pressure of the fault 1,650 feet (503 m) away; with The Zipingpu Dam is believed to have changed the pressure of the fault 1,650 feet (503 m) away; I think this is what the text is trying to say, but I am not quite sure.31.4.158.7 (talk)


 * Thanks for pointing that out. I've made a few other minor changes in addition to your suggestions. Mikenorton (talk) 13:44, 23 July 2020 (UTC)
 * I've rewritten the section, since the link between the earthquake and dam is not confirmed. Therefore, I brought up Oklahoma instead, which is confirmed. ◢  Ganbaruby!   (Say hi!) 13:53, 23 July 2020 (UTC)
 * That's certainly an improvement, thanks. Mikenorton (talk) 15:02, 23 July 2020 (UTC)

Earthquake
The general opinion is that an earthquake is caused by the movement of the plates Is there A chance of a new split in the plate? — Preceding unsigned comment added by 112.133.236.236 (talk) 15:00, 3 February 2021 (UTC)

Proposal of new Section about Co-seismic overpressuring and effect of pore pressure
Dear all, I would like to add a new section about this topic as it has been assessed more than half century ago. Such phenomenon is well known to geophysicists, although it is less known to the greater non specialized audience. I think that an explanation about co-seismic overpressuring is due in order to better understand the seismic phenomenon; furthermore it significantly affect the aftershock sequence and is also related to induced seismicity. I have already drafted a brief explanation (a very rough draft), which I will post here later in order to receive your opinion and some suggestion. Thanks Strucural geo (talk) 10:39, 24 March 2021 (UTC) I think this may be a sub-section of 'Rupture dynamic'. Al suggestions are welcome, thanks. Strucural geo (talk) 10:48, 24 March 2021 (UTC) This is a first proposal of the section text: During an earthquake, high temperatures can develop at the fault plane so increasing pore pressure consequently to vaporization of the ground water already contained within rock. To be continued.... Strucural geo (talk) 16:02, 24 March 2021 (UTC) Continuation In the coseismic phase, such increase can significantly affect slip evolution and speed and furthermore, in the post-seismic phase it can control the aftershock sequence as, after the main event, pore pressure increase slowly propagates into the surrounding fracture network. From the point of view of the Mohr-Coulomb strength theory, an increase in fluid pressure reduces the normal stress acting on the fault plane that holds it in place, furthermore fluids can exert a lubricating effect. If no one has anything against it, tomorrow I would post this change in the main article. All suggestion are welcome Strucural geo (talk) 18:16, 25 March 2021 (UTC) Continuation As thermal overpressurisation may provide a positive feedback between slip and strength fall at the fault plane, a common opinion is that it may enhance the faulting process instability. After the main shock the pressure gradient between the fault plane and the neighbouring rock causes a fluid flow which increases pore pressure in the surrounding fracture networks; such increase may trigger new faulting processes by reactivating adjacent faults, giving rise to aftershocks. Analogously, also manmade pore pressure increase, by means of fluid injection in Earth’s crust, may induce seismicity. All suggestion are welcome Strucural geo (talk) 19:02, 26 March 2021 (UTC)


 * Thanks for adding that section. I wonder about the use of the word vaporization as I suspect in many cases we are dealing with a supercritical fluid. I notice that Rick Sibson doesn't use "vapor" in his paper (although he does refer to "steam tables"). Mikenorton (talk) 20:59, 28 March 2021 (UTC)


 * Dear Mikenorton, thanks for your suggestion. I thought I was abandoned on this talk page. Maybe such concept should be better clarified. I'm sure that the fluid (mainly ground water) is not a supercirical one in the main cases, as such phenomenon is most significant for shallow earthquakes, ie. having ipocenter at a depth lesser than 10km (where temperatures are usually lesser tha 300°C). This is well explained in the cited references, particularly in the most recent one (Guerriero et al., 2021).


 * That Guerriero and Mazzoli paper is a very useful review. It's also a handy update for me on my lectures in the late 1970s from Neville Price, John Cosgrove, Ernie Rutter and Rick Sibson, all of whom drummed into me the importance of effective stress in rock deformation, so thanks for that. That paper does support "vaporization", at least for shallower focus earthquakes. The change to supercritical at about 370°C may affect the volume around the earthquake origin, but the rupture would in most case extend to shallower depths, so that's fair enough I think. Mikenorton (talk) 08:15, 31 March 2021 (UTC)

In next days I want to clarify this concept, nevertheless if someone ha some suggestion about this would be welcome. Thanks. Strucural geo (talk) 13:26, 30 March 2021 (UTC)

Semi-protected edit request on 3 August 2021
This edit should be reverted. 50.239.222.190 (talk) 03:35, 3 August 2021 (UTC)
 * ✅ Dawnseeker2000  03:57, 3 August 2021 (UTC)

Wiki Education Foundation-supported course assignment
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Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 19:59, 16 January 2022 (UTC)

Semi-protected edit request on 21 February 2022
it is geographically incorrect ShinyShuckle (talk) 11:02, 21 February 2022 (UTC)
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. Dawnseeker2000  12:12, 21 February 2022 (UTC)

Flood induced earthquakes
I would like to add to Causes section: "Flood induced" I would like add to "Contents" section: "1.8 Flood induced" Final Text to add

===Flood Induced Earthquakes=== Floods may trigger a seismic zone fault failure as the flood mass moves over a fault such as the New Madrid Seismic Zone near the Mississippi River, see Flood triggering of earthquakes for details.

I'll build the "Flood triggering of earthquakes" page tomorrow.

John Huebner, Theoretical Physicist — Preceding unsigned comment added by John Huebner (talk • contribs) 17:49, 4 October 2016 (UTC)

Weak sourcing on climate change

 * "In recent studies, geologists claim that global warming is one of the reasons for increased seismic activity. According to these studies, melting glaciers and rising sea levels disturb the balance of pressure on Earth's tectonic plates, thus causing an increase in the frequency and intensity of earthquakes. "

The source is rather weak; this section should probably be rewritten from stronger sources like. — Preceding unsigned comment added by Rolf h nelson (talk • contribs) 03:32, 19 June 2020 (UTC)

Earthquake
Earthquake is a common natural disaster. When tectonic plates are healed by and by then Earth shakes.Then we need equipment protect from earthquake? 2409:4042:4E1F:BA2B:7421:9843:72EE:4518 (talk) 05:15, 28 February 2022 (UTC)

Semi-protected edit request on 21 October 2022 (2)
The title Intensity of earth quaking and magnitude of earthquakes should be changed to Intensity and magnitude of earthquakes the term "quaking" is unscientific and confusing because it is redundant.

Under the same section, the first paragraph is confusing, messy and does not clarify the difference referenced in the heading. It should be changed from: "Quaking or shaking of the earth is a common phenomenon undoubtedly known to humans from the earliest times. Before the development of strong-motion accelerometers that can measure peak ground speed and acceleration directly, the intensity of the earth-shaking was estimated based on the observed effects, as categorized on various seismic intensity scales. Only in the last century has the source of such shaking been identified as ruptures in the Earth's crust, with the intensity of shaking at any locality dependent not only on the local ground conditions but also on the strength or magnitude of the rupture, and on its distance.[33]"

To: "Shaking of the earth is a common phenomenon that has been experienced by humans from the earliest of times. Before the development of strong-motion accelerometers the intensity of the shaking was estimated based on the observed effects. Magnitude and intensity are not directly related. The magnitude of an earthquake is a single value that describes the size of the earthquake at its source. Intensity is the measure of shaking at different locations around the earthquake. Intensity values vary from place to place, depending on distance from the earthquake and underlying rock or soil makeup."

Sources: https://opentextbc.ca/geology/chapter/11-3-measuring-earthquakes/ https://www.usgs.gov/programs/earthquake-hazards/earthquake-magnitude-energy-release-and-shaking-intensity --EricFishers11 (talk) 04:08, 21 October 2022 (UTC) EricFishers11 (talk) 04:08, 21 October 2022 (UTC)


 * I see that you have already made the change, which certainly reads better, thanks. Mikenorton (talk) 14:21, 23 October 2022 (UTC)
 * Excellent, good to hear.  EricFishers11 (talk) 19:41, 23 October 2022 (UTC)

Semi-protected edit request on 21 October 2022
To support CactiStaccingCrane request for cleanup: Except for the first line: "An earthquake (also known as a quake, tremor or temblor)" all references to the term "quake" as a noun in this article should be replaced with the scientific term "earthquake". The term “Quake” is not a scientific term and is not formally used. It is primarily used as a verb and only informally as a noun. The global authority on earthquakes, the USGS does not reference seismic activity using quake anywhere in their research or literature. It is non-scientific and more slang for the word earthquake. EricFishers11 (talk) 03:24, 21 October 2022 (UTC)


 * I don't much like the use of "quake" and I generally replace it in our earthquake articles when I find it, but the term is in very widespread general use, even I find very occasionally by the USGS, so it should be in there as an alternative. Mikenorton (talk) 14:07, 23 October 2022 (UTC)
 * Do you feel the mention in the first sentence is sufficient? "An earthquake (also known as a quake, tremor or temblor)" EricFishers11 (talk) 19:43, 23 October 2022 (UTC)

Resolved
Two sections have had this tag added and I have attempted to address the "Rupture dynamics" section and would appreciate comments. The second section on "Co-seismic overpressuring and effect of pore pressure" is more problematic and the editor that added it is globally blocked, so I will attempt to simplify and shorten the section, probably just as a third short paragraph in the "Rupture dynamics" section, rather than its own sub-section. Mikenorton (talk) 14:34, 26 October 2022 (UTC)


 * That sounds great. I did my best to do the same for Rupture dynamics a while ago - It reads more like a scientific hypothesis than widely accepted fact. Perhaps this and the following section was research from the blocked user? Many of the sources cite research from "Guerriero, V; Mazzoli" It has some good information but certain parts seem unsupported. EricFishers11 (talk) 18:59, 26 October 2022 (UTC)
 * Re-reading, there is quite a bit of speculative and opinion language including "appear," "poorly understood," "may continue." I'm at a loss on how to best fix it. EricFishers11 (talk) 19:15, 26 October 2022 (UTC)
 * I've changed two of those to be less equivocal, which actually reflects the cited source, but the same source says "The mechanics of rupture propagation are complex and poorly understood", so that is where we are. Mikenorton (talk) 20:22, 26 October 2022 (UTC)


 * I recommend being ruthless, removing anything that can't be verified with at least two independent sources. That criterion alone may make half these sections melt away. --Kent G. Budge (talk) 19:20, 26 October 2022 (UTC)
 * Think you can take a stab at it? I'm fairly new to Wiki editing and am wary of removing too much without more experience. EricFishers11 (talk) 19:32, 26 October 2022 (UTC)
 * Not any time soon. I'm writing from a hospital bed -- near-fatal car wreck. I can give advice if that will help. Kent G. Budge (talk) 19:39, 26 October 2022 (UTC)
 * Sorry to hear that - wishing you a speedy recovery. From the citation source: "An important research area is how ruptures in earthquakes compare with idealizations of rupture based on fracture mechanics"
 * National Academies of Sciences, Engineering, and Medicine. 2003. Living on an Active Earth: Perspectives on Earthquake Science. Washington, DC: The National Academies Press. https://doi.org/10.17226/10493.
 * All of "Rupture Dynamics" comes from this one source and it seems to an ongoing area of research. It seems this section needs to be cut way back. EricFishers11 (talk) 20:15, 26 October 2022 (UTC)
 * After edit conflict - Sorry to hear that you're laid up, but I would point out that the source used to support this is a major review work, albeit from 2003, from the Committee on the Science of Earthquakes of the National Academy of Sciences. I've looked for a more recent review, but have so far failed to find one. I'll keep looking, if only to work out what to keep of the Overpressuring sub-section. Also this is science, everything is always an ongoing area of research. Mikenorton (talk) 20:22, 26 October 2022 (UTC)
 * Good points, I'll take one more try at editing "Rupture Dynamics" - feel free to undo EricFishers11 (talk) 20:29, 26 October 2022 (UTC)
 * Ended up not editing "Rupture Dynamics" directly - its in my sandbox if you want to take a look. You're way more qualified (according to you talk) to gauge if this section is sufficient now - feel free to update the tags EricFishers11 (talk) 23:57, 26 October 2022 (UTC)

Semi-protected edit request on 26 March 2023
change "He also used earthquakes to punish and inflict fear upon people as revenge" to "He also used earthquakes to punish and inflict fear upon humanity as revenge." 2001:F40:983:BF49:4368:2221:FEC1:FA7 (talk) 03:28, 26 March 2023 (UTC)
 * Red information icon with gradient background.svg Not done: In Greek mythology, these actions by Poseidon were hardly aimed at (or affected) humanity as a whole. Actualcpscm (talk) 12:11, 26 March 2023 (UTC)

Semi-protected edit request on 16 July 2023
Earthquake us a sudden releaseof energy 103.218.237.250 (talk) 06:59, 16 July 2023 (UTC)
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate.  — Paper9oll  (🔔 • 📝)  09:24, 16 July 2023 (UTC)

Proposed merge of Seismicity into Earthquake
The redirect seismic activity points to earthquake, which defines "seismicity" in the lead (average rate of seismic energy release per unit volume). fgnievinski (talk) 14:19, 8 September 2022 (UTC)


 * I think that "Seismic activity" should actually point at "Seismicity" as the latter is effectively just a shortening of the former. I feel that the "seismicity" article could and should be expanded, to include, amongst other things, induced seismicity. I'll see what I can come up with. Mikenorton (talk) 11:19, 10 October 2022 (UTC)
 * Seismicity is simply a measure of the frequency and size of earthquakes in a given region over an amount of time. I agree, it could easily merge under the Earthquakes article. EricFishers11 (talk) 05:48, 22 October 2022 (UTC)
 * Some have labelled the earthquake article a mess as it mixes technical and more plain english. I am all for keeping seismicity separate for those who want to explore a technical topic. Its a bit like saying weather forecasting measurement can be dealt with in the forecasting section of the weather page ChaseKiwi (talk) 17:42, 8 July 2023 (UTC)

Semi-protected edit request on 4 November 2023
Kritiraj1977 (talk) 07:16, 4 November 2023 (UTC) https://techyidiot.com/news-earthquake-today-3-november-2023-important-lessons-needs-to-learned-from-the-earthquake/
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. (OP blocked for spamming) Victor Schmidt (talk) 08:37, 4 November 2023 (UTC)