Talk:2004 Indian Ocean earthquake and tsunami

Magnitude

Template:Replyto I'm not sure about changing the magnitude. A very quick analysis of the titles of papers listed using the ISC link (all 959 of them) in the infobox gives the following number of mentions: 9.0 12, 9.1 9, 9.2 14, 9.3 11, although of course that's just the titles, but it is indicative that we should be keeping a bigger range than just 9.2–9.3. Mikenorton (talk) 21:08, 19 May 2024 (UTC) And the USGS use 9.1 referring to Duputel et al. (2012, although confusingly they give 9.2 MAG in the paper. Mikenorton (talk) 21:18, 19 May 2024 (UTC)

I based it off the revised magnitudes in the most recent studies, such as Kenji Satake and colleagues revising their magnitude from Mw 9.1 in 2007 to Mw 9.2 in 2017, the 2016 Bletery et al study which gives Mw 9.25 and notes its close to the Mw 9.3 obtained through normal mode analyses. The "latest" study in the 2000s which actually calculates the magnitude, from what I've been able to find, is the 2007 study by Stein and Okal of Mw 9.3. There's this 2017 study as well of Mw 9.35, though you may want to look at it. Reaper1945 (talk) 21:24, 19 May 2024 (UTC)

The USGS really does not seemingly update its figures, just gives 9.1 for both Tohoku and Sumatra, and then you note the study they cite giving 9.2. Reaper1945 (talk) 21:26, 19 May 2024 (UTC)

Even for the 1964 Alaskan earthquake, only one study gives a figure of 9.2, all studies well after it give it 9.07, 9.12, or 9.14. Reaper1945 (talk) 21:30, 19 May 2024 (UTC)

I note that Gopinathan et al. (2017) were not attempting to recalculate the magnitude. They themselves think that the high slips in the northern part of the rupture that their inversion produces are not real but a result of thick soft sediments beneath the seabed. Any reduction in slip would lead to a lower estimated magnitude (as they say). I'll take another look through the other more recent (since Stein & Okal) papers. Mikenorton (talk) 08:38, 20 May 2024 (UTC)

The most recent papers that set out to estimate magnitude (amongst other things) are Okal & Stein (2009) and Fujii et al. (2021). Okal & Stein confirm their earlier estimate of 9.3. Fujii et al. use tsunami data to invert for fault slip distribution and this gives a 9.2 magnitude, up from the 9.1 that they had previously calculated. In summary, 9.2–9.3 seems a fair range to have in the infobox. Mikenorton (talk) 11:13, 21 May 2024 (UTC)

But how did the 9.2 MAG estimate from Duputel get revised to 9.1 MAG by USGS Beluga732 (talk) 00:00, 16 May 2025 (UTC)

Semi-protected edit request on 25 December 2024

Under tsunami,sri lanka Dodandawa should be changed to Dodanduwa And Paiyagala to Payagala Thank you 2402:4000:13E1:F14A:47B:76B8:C44B:7761 (talk) 18:05, 25 December 2024 (UTC)

File: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 20:18, 25 December 2024 (UTC)

There's a typo in the request, but otherwise it's quite obvious that the IP was asking to correct the typo "Dodundawa" to Dodanduwa, which I've done. Paiyagala/Payagala seem to be alternative spellings, and the source does use Paiyagala, so I haven't changed that one. --Paul_012 (talk) 08:55, 26 December 2024 (UTC)

Semi-protected edit request on 22 February 2025

In the paragraph historical comparisons: Of all the moment released by earthquakes... Should read Of all the *movement* released by earthquakes i 47.210.200.228 (talk) 06:07, 22 February 2025 (UTC)

File:X mark.svg Not done: Sentence is correct. See seismic moment. Dawnseeker2000 07:19, 22 February 2025 (UTC)

The Earthquake's Magnitude Dispute

Does the USGS still estimate that the 2004 Indian Ocean earthquake was a Mw9.1 instead of a 9.2-9.3 of 10?

Do most sources state that the quake was a 9.2-9.3 of 10? Beluga732 (talk) 15:22, 4 April 2025 (UTC)

To a lesser extent, some sources have gone with the 9.1 given by USGS, and some papers published within a few months of the event used 9.1. A lot of papers don't stick to 1 magnitude figure but give a range inclusive of 9.1 Dora the Axe-plorer (explore) 16:30, 5 April 2025 (UTC)

Actually, despite the peer-reviewed studies and papers suggesting that the quake was a 9.2–9.3, the United States Geological Survey or USGS still estimates the quake to be a 9.1 as of the 20th anniversary of the event. USGS still did not revise its estimate yet. Additionally, due to lack of clear communication of the referencing of the MAG, this is impossible to prove that the 9.1 MAG estimate is cited wrong.

So, the actual range of MAG of the quake was:

9.1–9.3 MAG Beluga732 (talk) 22:31, 2 May 2025 (UTC)

We don't blindly take things at face value. The value 9.1 is an inconsistency and should be clarified Dora the Axe-plorer (explore) 23:27, 2 May 2025 (UTC)

As I have previously mentioned, the USGS 9.1 Mw is referenced to Duputel et al. (2012, which nowhere gives a value of 9.1, mentioning 9.15 and 9.30 for their W-phase inversion (see Figure 5) while their section 4.3.1 is entitled "Example: 2004 Sumatra–Andaman Islands earthquake (Mw= 9.2, id = 122604A)" I should probably try to get a response from them about this. Mikenorton (talk) 22:24, 22 April 2025 (UTC)

I've sent in a query, I'll report back if and when I get a response. I've changed the section title to "Magnitude" as that's what we're talking about. Mikenorton (talk) 22:43, 22 April 2025 (UTC)

Who says the value 9.1 is an inconsistency and should be clarified? Who says the value 9.1 is wrong? Is it out of date? Why does the consensus have to ignore the official value by USGS? Did USGS update its value to a 9.2?

Will the 2004 Indian Ocean earthquake be tied with the Great Alaskan earthquake at 9.2-9.3? Beluga732 (talk) 11:17, 3 May 2025 (UTC)

Because the value provided by USGS is taken from Duputel et al. (2012), which gave 9.2. Hence the USGS value should be 9.2, not 9.1. We are discarding the value because it appears incorrectly referenced. Furthermore no other academic papers use 9.1 when they reference this event; that can be taken as a scientific consensus that 9.2 (and 9.3) are likely more representative of the event Dora the Axe-plorer (explore) 11:58, 3 May 2025 (UTC)

A Possible Tie: Will the 2004 Indian Ocean earthquake be tied with the Great Alaskan earthquake as the 2nd strongest earthquake on record based on improving models, advancing technology, and recent studies and papers? Beluga732 (talk) 21:37, 6 May 2025 (UTC)

There is no dispute regarding magnitude. Please stop creating these discussions. Older papers are still valid and newer papers support a range of 9.0–9.3. Dawnseeker2000 21:47, 6 May 2025 (UTC)

Beluga732, will you please stop going around creating WP:HIJACK/R issues and making nonsensical comments in the articles? Dawnseeker2000 13:32, 3 May 2025 (UTC)

Sure, but I am trying to make an "invisible comment" that tells editors not to include "9.1" in the range of the 2004 Indian Ocean quake. Lets ignore the value "9.1" because it appears to be wrong after a study suggests it was a 9.2+. But how can I avoid hijacking the citations? I think I made a mistake. My bad! Beluga732 (talk) 14:12, 3 May 2025 (UTC)

Wikipedia:Don't hijack references is a short essay that says if there's an existing reference, then don't change the text to something that contradicts it. Dawnseeker2000 14:24, 3 May 2025 (UTC)

• I've had an initial response from the USGS, saying that their reading of the event page was that the Duputel et al. source was only used for the moment tensor and not the magnitude, despite what it appears to say. I was advised to contact another part of the USGS ( eq_questions@usgs.gov) asking for clarification, which I did, but have yet to receive a reply. That was two weeks ago, so I'm not holding out much hope as when I've received replies from them in the past it's happened quickly. Mikenorton (talk) 18:10, 8 May 2025 (UTC)

  Try this instead...

  1. Take a look at https://www.usgs.gov/programs/earthquake-hazards/science/20-largest-earthquakes-world-1900#overview.
  2. Scroll down to "#3".
  3. Scroll right to look for the reference.
  4. You could see that Duputel et al was cited for the MAG. This claim cannot guarantee 100% accuracy.

  Beluga732 (talk) 23:02, 12 May 2025 (UTC)

  You should've read Duputel et al. (2012), it also stated Mw 9.2 Dora the Axe-plorer (explore) 02:09, 13 May 2025 (UTC)

  Or, you may also use https://earthquake.usgs.gov/earthquakes/eventpage/official20041226005853450_30/executive to find out that 𝟡.𝟙 estimate came from. The fact that Duputel et al., which gave a 𝟡.𝟚 instead of a 𝟡.𝟙, appears to be true. However, its actually fake. Beluga732 (talk) 20:58, 13 May 2025 (UTC)

  Do you not understand how referencing works? Dora the Axe-plorer (explore) 01:15, 14 May 2025 (UTC)

(Earlier comment removed by author)

Wikipedia is not responsible for the USGS's public image, if their information contradicts their reference, it should not be included. And why have u started a new topic asking the exact same questions again when it's been addressed. Dora the Axe-plorer (explore) 01:26, 16 May 2025 (UTC)

If it's a widely cited figure, I think it would warrant at least a footnote explaining the error. --Paul_012 (talk) 15:27, 16 May 2025 (UTC)

• Actually, @Mikenorton had an initial response from the USGS, saying that their reading of the event page was that the Duputel et al. source was only used for the moment tensor and not the magnitude, despite what it appears to say. I viewed the official site claiming that USGS took the 9.1 value from Duputel et al., only to find out that it turned out to be fake. Beluga732 (talk) 23:12, 16 May 2025 (UTC)

Ask More Questions...

Let's solve the issue of whether or not the official value of 09.1 MAG should be in the range.

You may add the text "The official 9.1 MAG estimate by USGS appears to be currently out of date". Carefully compare the MAG estimates from the sources USGS and Duputel et al. (2012) and you should be able to find the discrepancy. Beluga732 (talk) 23:57, 15 May 2025 (UTC)

But how did the 9.2 MAG estimate from Duputel get revised to 9.1 by USGS? Beluga732 (talk) 23:58, 15 May 2025 (UTC)

As I stated above, the initial contact from the USGS pointed out that the only thing they took from Duputel et al. (2012) was the moment tensor. The USGS page gives the source of the magnitude Template:M under "Origin" as "USGS National Earthquake Information Center, PDE", so definitely not Duputel. As to why they put the text "Official Magnitude Reference:" next to the Duputel et al. reference, that's the thing that I'm still waiting to hear back about. This is not a satisfactory situation, but there's not a lot we can do. Mikenorton (talk) 21:41, 16 May 2025 (UTC)

Find the better option:

Keep the rating of MAG for the 2040 Indian Ocean earthquake at 9.2-9.3

Change the rating of MAG back to 9.1-9.3

• • Hint: The initial contact from the USGS pointed out that the only thing they took from Duputel et al. (2012) was the moment tensor. The USGS page gives the source of the magnitude M_w 9.1 under "Origin" as "USGS National Earthquake Information Center, PDE", so it's definitely not Duputel. As to why they put the text "Official Magnitude Reference:" next to the Duputel et al. reference, that's the thing that you're still waiting to hear back about.** Beluga732 (talk) 15:52, 18 May 2025 (UTC)

And...you just jumped to conclusion with this edit. Dora the Axe-plorer (explore) 04:05, 20 May 2025 (UTC)

N o t i c e !

Stop making false claims that the moment magnitude (M_w) is incorrectly cited. You seen to be confused with the difference between the moment magnitude (𝕄𝔸𝔾) and the moment tensor.

Moment magnitude (M_w) is a scale used to measure the size of earthquakes, primarily based on the seismic moment, which is the energy released during the earthquake. On the other hand, the moment tensor is a mathematical representation of the forces that drive the rupture of an earthquake. Beluga732 (talk) 22:09, 20 May 2025 (UTC)

Let's change the MAG to 9.1–9.3 for now. [end of discussion] Beluga732 (talk) 22:10, 20 May 2025 (UTC)

@Beluga732 the discussion has not been satisfactory, you do not get to impose your own feelings without an agreement with other editors on the matter. It is your WP:Burden to make sure everyone else agrees 2 extend the range. Your entire basis for arguing is an email correspondence from Mike—that's incomplete. Dora the Axe-plorer (explore) 00:57, 21 May 2025 (UTC)

Additional changes to the article and you will be reported to the administrators Dora the Axe-plorer (explore) 00:58, 21 May 2025 (UTC)

The official moment magnitude (Mw) rating is 9.1, as cited by the USGS and recognized by global seismological agencies (e.g., GCMT, ISC-GEM). This value is based on standardized seismic moment calculations and is widely accepted in academic and emergency planning literature.

That said, I fully acknowledge that some recent peer-reviewed studies suggest the energy release may have been equivalent to Mw 9.2–9.3, based on extended rupture and tsunami modeling. These findings are notable and can absolutely be included — but they should be presented as alternative estimates, not as replacements for the official rating.

Per Wikipedia’s policy on reliable sources and neutral point of view, we should clearly differentiate between the official magnitude and newer research findings, without just simply discarding or ignoring the globally accepted value.

If you believe that USGS's official estimate is incomplete or inaccurate, please leave a message in my user talk page. Beluga732 (talk) 21:37, 21 May 2025 (UTC)

Please be patient; don't rush to change information without clarification... Dora the Axe-plorer (explore) 01:18, 22 May 2025 (UTC)

Apologies for the confusion. I think I figured out my mistake. I didn't scroll down far enough in the USGS website and just relied on a Wilkipedian's email. To correct my mistake, I scrolled down farther to notice that USGS used Duputel's moment tensor instead of their final MAG estimate. And USGS's 9.1 MAG estimate originated from CMT. My bad! Beluga732 (talk) 20:03, 22 May 2025 (UTC)

Maybe could you stop changing the 9.1–9.3 MAG range back to 9.2–9.3? I found the "fault" in [official USGS website] to clarify that 9.1–9.3 should be used.

—i forgot to add that— Beluga732 (talk) 00:46, 23 May 2025 (UTC)

You are the one who should stop your problematic behaviour Dora the Axe-plorer (explore) 01:06, 23 May 2025 (UTC)

sorry, I just tried to seek consensus with you... Beluga732 (talk) 01:25, 23 May 2025 (UTC)

If you really don't want consensus so bad then...guess we might lose public trust. USGS spent so much hard work analyzing the MAG of the 2004 Indian Ocean earthquake. The standard 9.1 MAG estimate by USGS is being used for tsunami warnings, tectonic plate research, catalogs, building codes, and seismic hazard assessments. I know that many of all those new studies are proposing higher MAG estimates than 9.1, but we don't want our readers to get confused. Beluga732 (talk) 01:34, 23 May 2025 (UTC)

What the USGS does is none of Wikipedia's business. We are not responsible for explaining the discrepancy between the referenced work and what's been extrapolated. There is no consensus yet because it's only two editors in this discussion. Dora the Axe-plorer (explore) 03:57, 23 May 2025 (UTC)

Why not let's invite editors to intervene?

It looks like you are infringing WP:NPOV.

Why you don't want 9.1? Beluga732 (talk) 19:54, 23 May 2025 (UTC)

Would you like to get an "admin" or a "bot" so that it can intervene? Beluga732 (talk) 20:02, 23 May 2025 (UTC)

Nothing to intervene, you just need a consensus. And btw what in the world compelled you to edit my own user page? Are those warnings not enough to deter you from being disruptive? Dora the Axe-plorer (explore) 03:56, 24 May 2025 (UTC)

I am just trying to fix your grammar. Grammar mistakes are not so professional. I'm not trying to disrupt this community, nor vandalizing it. Beluga732 (talk) 21:23, 24 May 2025 (UTC)

Well, don't. Nobody asked you 2 do that... Dora the Axe-plorer (explore) 00:17, 25 May 2025 (UTC)

Template:Od Outdenting to make navigation easier. I just checked the latest version of the ISC-GEM catalogue, which gives Template:M. I also came across Hayes et al. (2020), a USGS publication titled "Seismicity of the Earth 1900–2018", which gives Template:M for this earthquake. Why the ANSS (an organisation that includes both the USGS and many other US groups - we tend to call them the USGS but that's not strictly true) still persists with 9.1, we can't speculate. The problem is how exactly to express the magnitude uncertainty. Note that this is not a dispute, just a difference of opinion between groups of scientists, possibly even within a single organisation, potentially at different times. Mikenorton (talk) 21:09, 23 May 2025 (UTC)

To repeat my previous thoughts on this (see top of page) "The most recent papers that set out to estimate magnitude (amongst other things) are Okal & Stein (2009) and Fujii et al. (2021). Okal & Stein confirm their earlier estimate of 9.3. Fujii et al. use tsunami data to invert for fault slip distribution and this gives a 9.2 magnitude, up from the 9.1 that they had previously calculated. In summary, 9.2–9.3 seems a fair range to have in the infobox." I would add that 9.2–9.3 would also be appropriate for the lead section. Other values are already mentioned in the "Earthquake" section. Mikenorton (talk) 21:20, 23 May 2025 (UTC)

Out of these bullets below, choose the bullets that explain why 9.1 should not be in the range of uncertainty in this Wikipedia article (select all that apply; you can word your answer whatever you want):

• 9.1 is incomplete.
• 9.1 is referenced wrong.
• 9.1 is not justified or clarified.
• 9.1 is out of date.
• 9.1 is getting increasingly debated.
• More studies say that the earthquake was 9.2+.
• Not enough studies rate the quake a 9.1.
• Other...

Beluga732 (talk) 16:36, 25 May 2025 (UTC)