# Geology buffs of the Dope, what's going on in the Mid-Atlantic Ridge? **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Tags:** science-math\ **Created:** [October 1, 2022, 1:54am UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529 "2022-10-01T01:54:20Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [October 1, 2022, 1:54am UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/1 "2022-10-01T01:54:20Z")
A place south of Greenland/Iceland is seeing a lot of seismic activity in recent days, and as I speak, a quake-cam I sometimes follow is tracing some nice squiggles from a 5.9 in the region. Is an underwater volcano erupting, or do they know? What is the risk of a tsunami, if any? I find all of this quite interesting. ---
**Author:** ![PatrickLondon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/patricklondon/32/4422_2.png) [@PatrickLondon](https://boards.straightdope.com/u/PatrickLondon)\ **Post date:** [October 1, 2022, 1:42pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/2 "2022-10-01T13:42:02Z")
I blame the Russians. ---
**Author:** ![terentii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/terentii/32/212_2.png) [@terentii](https://boards.straightdope.com/u/terentii)\ **Post date:** [October 1, 2022, 4:54pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/3 "2022-10-01T16:54:43Z")
How close is it to an actual fault line? ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [October 1, 2022, 6:45pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/4 "2022-10-01T18:45:01Z")
Right on it; it’s just that a lot of quakes are happening in the same place all at once. ---
**Author:** ![carnut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnut/32/3531_2.png) [@carnut](https://boards.straightdope.com/u/carnut)\ **Post date:** [October 1, 2022, 10:00pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/5 "2022-10-01T22:00:22Z")
Every time I see something like this, I go check to see if [Surtsey](https://en.wikipedia.org/wiki/Surtsey) is in the news. I still remember the excitement of the new island being explained to me as a wee child. ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [October 1, 2022, 10:16pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/6 "2022-10-01T22:16:24Z")
I think Anak-Krakatoa (“Child of Krakatoa”) is pretty cool, too. I had heard of Surtsey, but didn’t know until just now that it formed from TWO adjoining vents. Yep, it has two craters. If vegetation starts to sprout on this new Tongan island, that will definitely slow down erosion. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [October 2, 2022, 9:11am UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/7 "2022-10-02T09:11:04Z")
> [@nearwildheaven](#): > > If vegetation starts to sprout on this new Tongan island, that will definitely slow down erosion. That’s not what consolidates new volcanic islands. There’s no soil for plants to grow in on such an island, just volcanic rock and ash. It’ll be many years before substantial plants will grow on a new volcanic island. What’s needed is for the volcano’s mouth to be isolated from the ocean water and then for it to pour out a bunch more lava to cover the loose rock. When lava hits water, it explodes, which means the lava is broken up into smallish rocks. If the volcano can grow big enough to send the lava into air, the lava could consolidate that loose rock into a more permanent island. ---
**Author:** ![Bullitt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bullitt/32/5725_2.png) [@Bullitt](https://boards.straightdope.com/u/Bullitt)\ **Post date:** [October 2, 2022, 3:15pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/8 "2022-10-02T15:15:43Z")
Hmmm, I’m not seeing those quakes. Living in the San Francisco area, I have a vested interest and I’ve signed up for the USGS alerts but I haven’t gotten any for that area. Are they recent quakes, within the last month? [![](https://i.imgur.com/VcIhPns.png) ](https://i.imgur.com/VcIhPns.png) ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 2, 2022, 3:30pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/9 "2022-10-02T15:30:06Z")
The ice melt is creating changes in the earth’s gravity in the area. The weight of the land and water over the sea bed are changing. I can’t recall what this phenomena is called but it results in an actual sea level drop locally and rise far away. The local changes in gravity could easily induce seismic activity. ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [October 2, 2022, 7:01pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/10 "2022-10-02T19:01:35Z")
Here’s a link to a map. You can move the map around to anywhere in the world. [https://earthquake.usgs.gov/earthquakes/map/?extent=21.37715,-153.10547&extent=63.90152,-46.23047](https://earthquake.usgs.gov/earthquakes/map/?extent=21.37715,-153.10547&extent=63.90152,-46.23047) ---
**Author:** ![AK84](https://avatars.discourse-cdn.com/v4/letter/a/85e7bf/32.png) [@AK84](https://boards.straightdope.com/u/AK84)\ **Post date:** [October 2, 2022, 7:26pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/11 "2022-10-02T19:26:37Z")
Paging our resident geologist @MrDibble ---
**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\ **Post date:** [October 2, 2022, 7:31pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/12 "2022-10-02T19:31:14Z")
I’m not a geology buff, but since you haven’t had a geologist reply yet. It’s the Mid-Atlantic ridge. The continental plates are pulling apart (which I’m sure you know) and it has seismic activity all the time. Here’s a map for the North Atlantic part of the ridge for this year to date. Earthquakes all up and down the ridge. [https://earthquake.usgs.gov/earthquakes/map/?extent=19.47695,-108.80859&extent=75.27541,59.0625&range=search&listOnlyShown=true&search={"name":"Search%20Results","params":{"starttime":"2022-01-01%2000:00:00","endtime":"2022-10-02%2023:59:59","maxlatitude":69.543,"minlatitude":36.334,"maxlongitude":-2.438,"minlongitude":-47.438,"minmagnitude":2.5,"orderby":"time"}}](https://earthquake.usgs.gov/earthquakes/map/?extent=19.47695,-108.80859&extent=75.27541,59.0625&range=search&listOnlyShown=true&search=%7B%22name%22:%22Search%20Results%22,%22params%22:%7B%22starttime%22:%222022-01-01%2000:00:00%22,%22endtime%22:%222022-10-02%2023:59:59%22,%22maxlatitude%22:69.543,%22minlatitude%22:36.334,%22maxlongitude%22:-2.438,%22minlongitude%22:-47.438,%22minmagnitude%22:2.5,%22orderby%22:%22time%22%7D%7D) As a non-expert I’d say you are looking at random noise in a noisy system. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [October 2, 2022, 7:40pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/13 "2022-10-02T19:40:07Z")
The Northern Mid-Atlantic Ridge activity (which is pretty much constant) generally isn’t, by its divergent nature, likely to cause the kind of tsunamis most folks need to worry about. In contrast to the convergent margins that cause all the trouble in the Pacific and Indian Oceans. Here, [have a paper on it](https://www.researchgate.net/publication/248444649_Why_the_Atlantic_generally_cannot_generate_transoceanic_tsunamis). ---
**Author:** ![Bullitt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bullitt/32/5725_2.png) [@Bullitt](https://boards.straightdope.com/u/Bullitt)\ **Post date:** [October 2, 2022, 7:44pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/14 "2022-10-02T19:44:49Z")
> [@nearwildheaven](#): > > Here’s a link to a map. You can move the map around to anywhere in the world. > > [Latest Earthquakes](https://earthquake.usgs.gov/earthquakes/map/?extent=21.37715,-153.10547&extent=63.90152,-46.23047) Got it. Thanks for that. ---
**Author:** ![Zyada](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zyada/32/3028_2.png) [@Zyada](https://boards.straightdope.com/u/Zyada)\ **Post date:** [October 2, 2022, 8:59pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/15 "2022-10-02T20:59:54Z")
This is my preferred map for seismic activity. > **[Seismic Monitor. A colorful, interactive map of the latest earthquakes and...](http://ds.iris.edu/seismon/index.phtml)** > > Up-to-date map of the latest earthquakes with resources like news, lists, tools and a 3D viewer. If you drill into the Mid-Atlantic area, you can get a list of recent earthquakes. I played around with it, and got here: > **[IRIS Earthquake Browser](http://ds.iris.edu/ieb/index.html?format=text&nodata=404&starttime=2022-09-25&endtime=2025-01-01&minmag=0&maxmag=10&mindepth=0&maxdepth=900&orderby=time-desc&src=iris&limit=200&maxlat=55.610&minlat=52.010&maxlon=-33.410&minlon=-37.010&sbl=1&caller=smevlnk&evid=11603142&name=VICINITY%20of%20REYKJANES%20RIDGE&zm=7&mt=sat)** > > Explore 5.4 million earthquakes on a Google map with ability to rotate thousands of quakes in 3D and export to Excel. A bookmarkable, remarkable tool!. That’s the last week of activity and you can animate to see all the quakes pop up ---
**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\ **Post date:** [October 2, 2022, 9:06pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/16 "2022-10-02T21:06:08Z")
> [@TriPolar](#): > > The ice melt is creating changes in the earth’s gravity in the area. The weight of the land and water over the sea bed are changing. I can’t recall what this phenomena is called but it results in an actual sea level drop locally and rise far away. > > The local changes in gravity could easily induce seismic activity. You also have isostatic rebound, which could also be caused by the removal of the weight of the ice, in which the rock expands due to less pressure, which could cause sea level rise in some places and a fall other places, and could also lead to seismic activity. Although I do not know how soon that would happen or at what distance. ---
**Author:** ![Bullitt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bullitt/32/5725_2.png) [@Bullitt](https://boards.straightdope.com/u/Bullitt)\ **Post date:** [October 2, 2022, 9:24pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/17 "2022-10-02T21:24:26Z")
Thanks @Zyada ! ---
**Author:** ![nearwildheaven](https://avatars.discourse-cdn.com/v4/letter/n/90db22/32.png) [@nearwildheaven](https://boards.straightdope.com/u/nearwildheaven)\ **Post date:** [October 2, 2022, 10:12pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/18 "2022-10-02T22:12:14Z")
Or, for that matter, how thick an ice sheet would need to be or how rapidly it would have to shrink in order to cause measurable quakes. I have heard that there’s an island in either the Azores or the Canary Islands that has the potential to generate a tsunami, should part of it break off in a landslide. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 2, 2022, 10:22pm UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/19 "2022-10-02T22:22:15Z")
Those things could be working together. But I don’t know if any recent activity is directly related. There’s just a lot of things going on right around there and everywhere else affected by the ice melts and all the other seismic activity. Some days in that region are likely to be shakier than others. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [October 3, 2022, 6:51am UTC](https://boards.straightdope.com/t/geology-buffs-of-the-dope-whats-going-on-in-the-mid-atlantic-ridge/972529/20 "2022-10-03T06:51:55Z")
Any activity from isostatic rebound is going to pale into insignificance compared to the activity produced by the Ridge itself. Especially the Reykjanes Ridge portion, where you have that powerful combo of a spreading centre _and_ a [hotspot](https://en.wikipedia.org/wiki/Iceland_hotspot). > [@nearwildheaven](#): > > I have heard that there’s an island in either the Azores or the Canary Islands that has the potential to generate a tsunami, should part of it break off in a landslide. [La Palma in the Canaries.](https://en.wikipedia.org/wiki/Cumbre_Vieja_tsunami_hazard)