Talk:2019–20 Puerto Rico earthquakes/Archive 1

Poorly written article
This is a poorly written article. It's lacking in information and reads more like a bad news article. The title itself makes it sound like it's about one single earthquake when there's been at least two different ones. — Preceding unsigned comment added by 108.53.6.133 (talk) 21:47, 7 January 2020 (UTC)

Move to "earthquakes"
Following the continuation of the sequence, with tremors up to 5.9, it seems time to move the article to the plural name. Mikenorton (talk) 18:09, 11 January 2020 (UTC)∆
 * Yes. I think so too.--The Eloquent Peasant (talk) 18:39, 12 January 2020 (UTC)

Move to 2019–2020 Puerto Rico earthquakes
With the benefit of hindsight, I should probably have named this article 2019–2020 Puerto Rico earthquakes. I'll make that change now, but feel free to revert and discuss. Mikenorton (talk) 09:48, 31 January 2020 (UTC)

Causative fault
I'm not sure if this is an error with the USGS, but there appears to be two mainshocks

The Punta Montalva Fault makes an unlikely candidate for the causative fault as it is thought to involve left-lateral strike slip movement on a fault trending WNW–ESE. The M6.4 event was caused by slightly oblique normal faulting on a fault trending WSW–ENE, which doesn't really fit at all, although there are several mapped normal faults of that trend in the general area of the earthquakes. Of the twelve M≥5 earthquakes for which the USGS has published focal mechanisms, 7 were the result of slightly oblique normal faulting trending WSW–ENE, four were the result of slightly oblique strike-slip faulting trending WNW–ESE (parallel to the Punta Montalva Fault) and one had a strike-slip mechanism but a WNW–ESE trend. The full story will no doubt be told in due course, although it seems likely that there are many faults involved. However, the one source that we have that discusses this (the USGS page only used the Punta Montalva Fault as a boundary to the area of the earthquakes) clearly states that "The largest shock in Puerto Rico in 100 years struck on a fault discovered only several years ago", so that's what we run with for now. I await the scientific papers that will no doubt appear over the next few years with great interest. Mikenorton (talk) 20:49, 6 May 2020 (UTC)


 * IMO, the May 2 earthquake has the experts reassessing their prior inclinations. I agree with the generality of your view above, but the question now is, can we find a WP:RS that supports it? If we can locate one, then let's go ahead and replace the Punta Montalva cite with it. If we can't, or if we can't yet, then I would suggest this course of action: (1) Leave it as it is for now, and until a good cite to support the views above can be located, and (2) use the or similar template to add in your line of thought above indicating that the Punta Montalva fault will be re-evaluated as new geologists' findings refocuses on a different culprit. One action I would avoid is to leave blank the infobox entry in question, as that can leave it vulnerable to constant changes (Read: edit warring) based, precisely, on the different current theories floating around. Mercy11 (talk) 03:31, 7 May 2020 (UTC)


 * Yes, it's just our opinion for now, I have no intention of changing the infobox without a decent source to back it up. This was just to alert anyone interested that this interpretation of the faulting is not set in stone. Mikenorton (talk) 07:02, 7 May 2020 (UTC)

Two mainshocks?
I'm not sure if this is an error with the USGS earthquake feed, but there appears to be a 6.6 mainshock one second after (08:24:26) the 6.4. Here's the link to it:
 * M 6.6 - 10km S of Indios, Puerto Rico
 * M 6.4 - 13km S of Indios, Puerto Rico

Could this be a duplicate or there really is a bigger earthquake? Dora the Axe-plorer (talk) 15:38, 28 February 2021 (UTC)


 * Given the huge number of earthquakes in this swarm, it wouldn't be that surprising that there were two separate earthquakes very close in time. However, it still seems more likely that this was the same quake recorded twice - the 6.6 event was contributed by the National Tsunami Warning Center, not the main source for such things - the 6.4 quake in contrast was recorded by the NEIC and the Puerto Rico Seismic Network. The technical details for the 6.4 event also includes magnitude and location from the Pacific Tsunami Warning Center, which match closely with the later event. Note that the 6.6 event contains almost no other details. Mikenorton (talk) 21:45, 28 February 2021 (UTC)
 * The only paper published on this earthquake so far does not mention two shocks. Mikenorton (talk) 21:52, 28 February 2021 (UTC)