Talk:List of earthquakes in the United States

Pre-1776

This list includes 2 earthquakes from years prior to 1776: one in 1663 and the other in 1700. Since the United States did not exist prior to 1776, these are technically not "earthquakes in the United States" but rather "earthquakes in North America" or even "earthquakes in Spanish (or French) colonial territories." Why are they on this list? --Mûĸĸâĸûĸâĸû 07:41, 5 December 2008 (UTC)

Rename article?

I think it would be a good idea to rename this article 'List of major (or significant?) earthquakes in the United States'. As it stands it is open to confusion and will never be complete. Anybody object to it being renamed? Setwisohi (talk) 15:57, 8 November 2009 (UTC)

I don't think there is any problem with the current article name, it is the standard name for a list of earthquakes in a particular country such as List of earthquakes in China and List of earthquakes in Italy (see List of earthquakes for the others). None of the lists are ment to be a list of every earthquake ever recorded in the country. RapidR (talk) 21:10, 8 November 2009 (UTC)

Inclusion criteria

Clearly, this is not (and cannot be) a list of all earthquakes that have occurred in the U.S. Currently, we have a list comprised of notable earthquakes and a random selection of others. Unless someone has a better criterion for inclusion on the list, I'm going with a bluelink for an earthquake in the U.S. With this in mind, I'm yanking all of the redlinks. I'll pause for discussion on the following:

• Pre-1776 quakes. (e.g., 1663 Charlevoix earthquake) Not in the United States. I say they go.
• Pre-statehood quakes. (e.g., 1946 Alaska)
• Epicenter outside of the U.S., but felt in the U.S. (e.g., 1925 Charlevoix–Kamouraska earthquake) I feel this is rather vague and they should go.

Opinions? - SummerPhD (talk) 03:46, 24 August 2011 (UTC)

It should be a list of notable quakes (ie. there is a WP article - or should be) where the epicentre is in the US. An Earthquakes in the United States article can mop up the odd ones such as those that occurred in what is now the US and quakes that have had an effect on the US. I am in the process of making the list into a sortable wikitable and the points you mentioned threw me off track. -- Alan Liefting (talk) - 20:26, 26 August 2011 (UTC)

I think we're facing an uphill climb if we specifically limit this to quakes in areas that were part of the U.S. at the time of the quake. We already let the 1811-1812 New Madrid earthquakes slip by (statehood: 1822) and various quakes in Alaska in the 40s and 50s (statehood: 1959) will be added by every Tom, Dick and harry who happens by the article if we continue to remove them. Additionally, the non-arbitrary (but meaninglessness) of that criterion distorts reality: Alaska's record looks skimpy (compared to reality) because it's limited to 50 years while New Madrid doesn't show up at all. Comments? - SummerPhD (talk) 00:47, 8 September 2011 (UTC)

Inclusion criteria (again)

There are 60 earthquakes in the list for the period 1700 to 2003. Contrast that with 29 earthquakes from 2006 to 2015. I think that we need to tighten up on the criteria, listing only those events that have an article or for which an article is likely to be written. This needs to be done for other country lists as well - that is what a list article is supposed to be as I understand it (see Wikipedia:Manual_of_Style/Stand-alone_lists#Common_selection_criteria). Mikenorton (talk) 19:50, 2 May 2015 (UTC)

Yes, I'm on board. Hadn't been aware of the list criteria before, but that makes sense, and we should always be editing articles with long-range (good or featured status) goals in mind anyway. This does mean a lot of work (for all our lists) of removing the unfocused content now, and the ongoing battles with the Toms, Dicks, and Harrys (see above). Dawnseeker2000 16:12, 3 May 2015 (UTC)

Here's a suggested set of criteria:

For earthquakes:

1. The earthquake's epicenter was in the United States (including its territories and territorial sea) and the earthquake's magnitude was:

a. 7.5+ in the Aleutian Islands or Alaska Peninsula

b. 6.5+ in other seismically active areas

c. 5.5+ in areas which are not seismically active

2. Unless an earthquake was exceedingly strong for the impacted area, an earthquake that meets criteria 1 may be excluded if:

a. it was not felt by a significant number of people

b. caused very little damage

3. An earthquake that does not meet criteria 1 may be included if:

a. it was exceedingly strong in a highly populated region where earthquakes are not common, or

b. is notable for causing a significant amount of damage or more than five deaths, but consideration should be given to:

(1) the relationship between any death and the earthquake

(2) the year of the earthquake (older earthquakes were much more likely to cause damage and deaths even if they were not significantly strong)

4. The earthquake's epicenter was located outside the United States, but was felt in the United States (including its territories) and:

a. caused a significant amount of damage, or

b. caused more than five deaths, but discretion should be given to the year of the earthquake (see 2b(2))

For tsunamis:

1. Any tsunami is notable if it affects the coast of the United States (including its territories and the Great Lakes) and

a. is over 2 feet (0.7m) when it impacts the US coast, or

b. causes significant damage in the United States, or

c. causes any deaths in the United States, except that

d. for criteria 1a-1c, discretion should be given to exclude localized tsunamis with no substantial impact or damage

2. Nearly all tsunamis that occurred away from the coast (eg. dam collapse, underwater landslide in a lake) should not be included unless they are widely referred to as a "tsunami" by reliable sources and cause significant damage or deaths.

It's way too difficult to create an objective list of criteria, but I think the above is somewhat reasonable. Of course, the biggest problem with any objective criteria is that magnitude does not indicate an earthquake's impact, since the depth and local geology play a huge role in determining how much of an impact the quake has. However, the magnitude is at least a rough guide to serve as a starting point for the criteria. AHeneen (talk) 16:38, 3 May 2015 (UTC)

We do have these notability guidelines, which are pretty similar I think. In the end they need to be applied with common sense. Mikenorton (talk) 16:45, 3 May 2015 (UTC)

For list inclusion criteria we usually look for objective criteria from a reliable source. These criteria are a bit subjective ("significant" damage, "substantial" impact, etc.). I don't see a source for them, which makes me wonder why they are as complicated as they are (why 3 different magnitude limits based on location?

Long story short, I think blue-link notability is reasonable, objective and, honestly, a lot easier to build and maintain. - SummerPhD (talk) 17:01, 3 May 2015 (UTC)

(edit conflict) Looks like I spotted something shiny and wandered off after trying to take on this issue a few years back. It also looks like we have the same issues popping up periodically.

• It seems we're all on board with limiting the list to blue links (as the article now stands). Works for me.
• The current list does not make date distinctions for "in the United States" (1700 Cascadia, New Madrid, pre-1949 Alaska, etc.) I can see arguments for excluding them, but (at the moment) think maybe they should stay with a note that they were pre-statehood or some such.
• Epicenters outside the U.S. are currently in the article, but before the list. I think the distinction is a bit artificial. Are there any tsunamis with epicenters in the U.S.?
• I suppose there are tsunamis that have impacted various U.S. territories (especially those in the Pacific).

Thoughts? - SummerPhD (talk) 16:50, 3 May 2015 (UTC)

I don't really have time to write an extended commentary about this subject (as in spare time, not saying this to be rude). First, there are a couple things to consider:

• Lists should not be too broad and/or overlap a category (see WP:SALAT and WP:NOTESAL). A list article of every earthquake and tsunami in the US for which there is an article is far too broad, so it needs to be narrowed down to notable earthquakes and tsunamis. The title of this article should be changed to reflect that, eg. List of notable earthquakes and tsunamis in the United States or maybe just Notable earthquakes and tsunamis in the United States (it may also be worth considering separating earthquakes and tsunamis into different list articles). There could also be separate articles to cover the most powerful earthquakes in the US by superlative: List of strongest earthquakes in the United States/[state] (probably only the most earthquake-prone states would merit such a list), List of most expensive earthquakes in the United States, List of deadliest earthquakes in the United States, etc.
• While list criteria should be objective, this is a subject which is inherently subjective and thus criteria should be based on reliable sources (WP:LSC, guidelines in RSs discussed below). As a guideline, the LSC criteria should be applied with WP:COMMONSENSE (mentioned/linked in the guideline template at the top of the LSC page).
• Keep in mind that this article isn't well developed as far as comprehensiveness, mainly due to the lack of inclusion criteria, so the present state of the article shouldn't necessarily dictate how the notability guidelines are established.
• There will be an inherent bias to more recent earthquakes because of population growth, meaning that the quakes are more likely to be felt and recorded and that there is a greater likelihood of deaths and more property to be damaged. Nearly all Native Americans (in the US) did not have written records but used oral storytelling, which distorted the facts of events into legends, and it's difficult to use the geologic record to establish the notability of all but the strongest earthquakes (like Cascadia).

I searched about 12-15 pages of Google search results for "notable earthquakes US" and "list notable earthquakes". There were many based on superlative (strongest, deadliest, or strongest/deadliest in [region]) or short lists that compare less than 6-8 notable earthquakes (a few by news or educational sources, but most from unreliable sources). The only long lists of notable earthquakes published by reliable sources are:

• This one from the USGS does not give criteria and lists at least one from each state plus Guam & Puerto Rico, ostensibly meaning that they wanted to cover the entire US and that some of the quakes in states not prone to earthquakes may not be of substantial notability for this article. Note that the same list is also presented by date and by magnitude. They have a similar list of worldwide quakes, which doesn't cover every country and also seems to span a larger geographic area rather than focus on just notable ones.
• This one from Encyclopedia Britannica which doesn't provide selection criteria.

So for the selection criteria:

• The list should cover the area covered by the present-day US, including territories. I think a note should only be included if the area was not owned by the US at the time of the event, as opposed to using statehood as a guideline. For example, the Cascadia & New Madrid quakes are found on nearly every list of notable earthquakes in the US.
• There's not really any reliable source for what a "notable" earthquake is. I think the guidelines that User:Mikenorton mentions above are a good starting point and basically covers the underlying reasons for the proposed criteria I put forth. Magnitude isn't as notable in sparsely populated areas or in earthquake-prone areas, but "[u]nusually large events in areas of low seismicity" may be notable (eg. M5.8 2011 Virginia earthquake). "Deaths attributable directly to the earthquake (including any related tsunami) - i.e. not one heart attack that might have been caused by the 'quake" is what I said in 3b(1) and related to 3b(2) and 4b. Nonetheless, the guidelines should be modified for this list to make it easier to identify quakes that should be included.
• The criteria should provided magnitudes as a rough guide for inclusion. Separating the magnitude list into categories makes very good sense. Alaska accounts for over half of US earthquakes (57.2% of quakes over M3.5, 1974-2003 per USGS) and 7.0+ earthquakes are quite common (just glance at this list!). However, Alaska is also huge (22.5% the size of the contiguous 48 states) and sparsely populated, especially in the Aleutian Islands and Alaska Peninsula which is located along the Aleutian Trench subduction zone that causes a lot of the state's earthquakes and most M7+ quakes in the US.
• For tsunamis, 2 feet is just a rough guess as to what a notable coastal tsunami would be (equivalent to the magnitude/intensity criteria for earthquakes and subject to similar discretion about impact), because there are often small rises (<1ft) in sea level on the Pacific Coast from large earthquakes that have been called "tsunamis".

So in summary, the criteria are subjective, but should provide some objective criteria to be applied with common sense. The criteria for this article should be similar to the WikiProject:Earthquake guidelines, but slightly modified for the scope of this article to make it easier to identify events to list in this article. AHeneen (talk) 06:08, 5 May 2015 (UTC)

Unincorporated territories

I recently reverted that addition of an entry about the 2020 Puerto Rico earthquake because it affected an unincorporated territory, but I thought I should raise it here to check whether those areas should be included. Events like the 2009 Samoa earthquake and tsunami and the 1918 San Fermín earthquake would then be eligible. Any thoughts? Mikenorton (talk) 10:37, 9 January 2020 (UTC)

I imagine this might be similar to including the British Overseas Territories for the list of earthquakes in the United Kingdom. Mikenorton (talk) 20:37, 11 January 2020 (UTC)

Format issue: Dates sorted improperly

The table's sorting capability is broken with the current date format, sorting by names of the month instead of by year-month-day.Mousenight (talk) 05:28, 3 May 2020 (UTC)

An editor added a lot of earthquakes to the list a few months ago, but did not use the dts template for the dates, which is what broke the sorting. If I get a moment I'll update them - thanks for pointing out the issue. Mikenorton (talk) 07:43, 3 May 2020 (UTC)

All entries now use the Dts template and so should sort properly - now I just have to fix the untitled citations added by the same editor. Mikenorton (talk) 11:55, 5 May 2020 (UTC)

And those are done too. Now all I need to do is add all the missing magnitude types, assuming that's feasible. Mikenorton (talk) 17:10, 5 May 2020 (UTC)

Done, apart from the two Denver injection well quakes, which I could find nothing for. Mikenorton (talk) 11:38, 7 May 2020 (UTC)

2020 North Carolina earthquake

This morning, August 9, there was a 5.1 magnitude earthquake in the foothills of North Carolina. Is this considered significant enough for inclusion here? — Preceding unsigned comment added by 71.69.145.132 (talk) 15:48, 9 August 2020 (UTC)

It doesn't seem to be particularly notable, I've not seen any international coverage and the damage seems to very limited, so for now I would say definitely not. Mikenorton (talk) 16:21, 9 August 2020 (UTC)

List of deadliest earthquakes by states and territories

Hi. I think we need also this section in the article. Aminabzz (talk) 19:45, 16 October 2023 (UTC)