# Why no "Ring of Fire" around the Atlantic? **URL:** \ **Category:** Factual Questions\ **Created:** [February 13, 2019, 5:45pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479 "2019-02-13T17:45:56Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\ **Post date:** [February 13, 2019, 5:45pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/1 "2019-02-13T17:45:56Z")
So, there’s the ring of fire around the Pacific Ocean. Why no ring of fire around the Atlantic? What’s the difference ? ---
**Author:** ![wevets](https://avatars.discourse-cdn.com/v4/letter/w/e9a140/32.png) [@wevets](https://boards.straightdope.com/u/wevets)\ **Post date:** [February 13, 2019, 5:53pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/2 "2019-02-13T17:53:47Z")
The Pacific Plate is a large tectonic plate whose edges are the Ring of Fire - that’s where the magma comes up, more or less. The Atlantic is instead characterized by a large Mid-Atlantic Ridge in the middle between the North American and Eurasian Plates, so the magma comes up in the middle instead of around the edges. ---
**Author:** ![Andy\_L](https://avatars.discourse-cdn.com/v4/letter/a/c67d28/32.png) [@Andy\_L](https://boards.straightdope.com/u/Andy_L)\ **Post date:** [February 13, 2019, 5:56pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/3 "2019-02-13T17:56:12Z")
> [@wevets](#): > > The Pacific Plate is a large tectonic plate whose edges are the Ring of Fire - that’s where the magma comes up, more or less. > > The Atlantic is instead characterized by a large Mid-Atlantic Ridge in the middle between the North American and Eurasian Plates, so the magma comes up in the middle instead of around the edges. Just to elaborate - the Pacific is shrinking as the plates around it come together - the Ring of Fire is where the collision is happening. The Atlantic is growing - and the mid-Atlantic ridge is where the expansion is happening. Note that the east coast of North America has a large continental shelf, while the west coast doesn’t. ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [February 13, 2019, 5:59pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/4 "2019-02-13T17:59:19Z")
Of course, just as I was going to post the first response, SDMB goes down. :rolleyes: 😛 In addition to what’s already been posted, note that there _is_ volcanic activity; for example, in Iceland and Italy. ---
**Author:** ![Andy\_L](https://avatars.discourse-cdn.com/v4/letter/a/c67d28/32.png) [@Andy\_L](https://boards.straightdope.com/u/Andy_L)\ **Post date:** [February 13, 2019, 6:03pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/5 "2019-02-13T18:03:15Z")
> [@Johnny\_L.A](#): > > Of course, just as I was going to post the first response, SDMB goes down. :rolleyes: 😛 > > In addition to what’s already been posted, note that there _is_ volcanic activity; for example, in Iceland and Italy. And Iceland is on the Mid-Atlantic Ridge (Italy is in the area affected by the collision of the European and African plates) ---
**Author:** ![zimaane](https://avatars.discourse-cdn.com/v4/letter/z/a3d4f5/32.png) [@zimaane](https://boards.straightdope.com/u/zimaane)\ **Post date:** [February 13, 2019, 7:47pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/6 "2019-02-13T19:47:19Z")
There are volcanoes in the Caribbean, but that is down to the interaction of the Caribbean plate and the South American plate. ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [February 13, 2019, 8:07pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/7 "2019-02-13T20:07:05Z")
> [@Andy\_L](#): > > And Iceland is on the Mid-Atlantic Ridge (Italy is in the area affected by the collision of the European and African plates) Iceland is a hotspot, similar to the Hawaiian islands. Hotspots are something different than plate tectonics as far as where the volcanism comes from. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [February 13, 2019, 8:26pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/8 "2019-02-13T20:26:13Z")
> [@bump](#): > > Iceland is a hotspot, similar to the Hawaiian islands. Hotspots are something different than plate tectonics as far as where the volcanism comes from. Nope, sorry. It’s smack dab on the Mid-Atlantic Ridge. Go look at an undersea map of the Atlantic. The Ridge, by the way, is not fixed over a single area on the Earth as hotspots are. There was one (perhaps more) hot spot that started on North America and now is on the other side of the Ridge. This is because the Ridge drifts somewhat to the west. I forget the name of it off-hand, but it came up in a thread not too long ago. ---
**Author:** ![Andy\_L](https://avatars.discourse-cdn.com/v4/letter/a/c67d28/32.png) [@Andy\_L](https://boards.straightdope.com/u/Andy_L)\ **Post date:** [February 13, 2019, 8:36pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/9 "2019-02-13T20:36:41Z")
This site has a map of the Ridge [Mid-Atlantic Ridge - Wikipedia](https://en.wikipedia.org/wiki/Mid-Atlantic_Ridge) - it goes through the middle of Iceland. ---
**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:** [February 13, 2019, 8:58pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/10 "2019-02-13T20:58:47Z")
> [@dtilque](#): > > I forget the name of it off-hand, but it came up in a thread not too long ago. The Great Meteor/New England hotspot track. ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [February 13, 2019, 9:23pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/11 "2019-02-13T21:23:51Z")
No reason it can’t be both… but Iceland is definitely over a hot spot- what we see there isn’t normal mid-oceanic ridge behavior. [http://geologymatters.org.uk/2011/08/18/the-iceland-hot-spot/](http://geologymatters.org.uk/2011/08/18/the-iceland-hot-spot/) > **[Icelandic volcano sits on massive magma hot spot](https://www.sciencedaily.com/releases/2014/10/141024142011.htm)** > > New research shows that high mantle temperatures miles beneath the Earth's surface are essential for generating large amounts of magma. In fact, the scientists found that Iceland's Bardarbunga volcano lies directly above the hottest portion of the... and the most interesting (“Our model suggests that the initiation of the Iceland hotspot predates the opening of the North Atlantic by at least 70 m.y.”) [https://www.researchgate.net/publication/235982076\_Iceland\_hotspot\_track](https://www.researchgate.net/publication/235982076_Iceland_hotspot_track) ---
**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\ **Post date:** [February 14, 2019, 1:56am UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/12 "2019-02-14T01:56:22Z")
> [@Andy\_L](#): > > Just to elaborate - the Pacific is shrinking as the plates around it come together - the Ring of Fire is where the collision is happening. The Atlantic is growing - and the mid-Atlantic ridge is where the expansion is happening. So was the Pacific once much bigger? ---
**Author:** ![Aspidistra](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aspidistra/32/3894_2.png) [@Aspidistra](https://boards.straightdope.com/u/Aspidistra)\ **Post date:** [February 14, 2019, 2:33am UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/13 "2019-02-14T02:33:41Z")
Iceland is essentially in the (long, drawn-out) process of being created by volcanic activity. There’s a very nice graphic in (IIRC) the Volcano Museum in Reykjavik of the two sides of the island being ripped apart form each other and filled in up the middle by successive eruptions. If it keeps going at the current rate, it’ll end up as wide as Australia some day. In … oooh … just about a hundred million years or so ---
**Author:** ![Pork\_Rind](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pork_rind/32/111_2.png) [@Pork\_Rind](https://boards.straightdope.com/u/Pork_Rind)\ **Post date:** [February 14, 2019, 2:36am UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/14 "2019-02-14T02:36:39Z")
> [@Northern\_Piper](#): > > So was the Pacific once much bigger? In some ways of looking at it, you could say that the Pacific was nearly the whole deal. > **[Panthalassa](https://en.m.wikipedia.org/wiki/Panthalassa)** > > Panthalassa, also known as the Panthalassic Ocean or Panthalassan Ocean (from Greek πᾶν "all" and θάλασσα "sea"), was the vast superocean that encompassed planet Earth and surrounded the supercontinent Pangaea, the latest in a series of supercontinents in the history of Earth. During the Paleozoic–Mesozoic transition (c. 250 Ma), the ocean occupied almost 70% of Earth's surface, with the supercontinent Pangaea taking up less than half. The original, ancient ocean floor has now completely disap Th... ---
**Author:** ![Andy\_L](https://avatars.discourse-cdn.com/v4/letter/a/c67d28/32.png) [@Andy\_L](https://boards.straightdope.com/u/Andy_L)\ **Post date:** [February 14, 2019, 2:59am UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/15 "2019-02-14T02:59:46Z")
> [@bump](#): > > No reason it can’t be both… but Iceland is definitely over a hot spot- what we see there isn’t normal mid-oceanic ridge behavior. > > [http://geologymatters.org.uk/2011/08/18/the-iceland-hot-spot/](http://geologymatters.org.uk/2011/08/18/the-iceland-hot-spot/) > > [Icelandic volcano sits on massive magma hot spot | ScienceDaily](https://www.sciencedaily.com/releases/2014/10/141024142011.htm) > > and the most interesting (“Our model suggests that the initiation of the Iceland hotspot predates the opening of the North Atlantic by at least 70 m.y.”) > > [https://www.researchgate.net/publication/235982076\_Iceland\_hotspot\_track](https://www.researchgate.net/publication/235982076_Iceland_hotspot_track) Thanks. Learn something new everyday. > [@Northern\_Piper](#): > > So was the Pacific once much bigger? Oh, yes. ---
**Author:** ![PoppaSan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/poppasan/32/189_2.png) [@PoppaSan](https://boards.straightdope.com/u/PoppaSan)\ **Post date:** [February 15, 2019, 12:55am UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/16 "2019-02-15T00:55:59Z")
> [@bump](#): > > No reason it can’t be both… but Iceland is definitely over a hot spot- what we see there isn’t normal mid-oceanic ridge behavior. > > [http://geologymatters.org.uk/2011/08/18/the-iceland-hot-spot/](http://geologymatters.org.uk/2011/08/18/the-iceland-hot-spot/) > > [Icelandic volcano sits on massive magma hot spot | ScienceDaily](https://www.sciencedaily.com/releases/2014/10/141024142011.htm) > > and the most interesting (“Our model suggests that the initiation of the Iceland hotspot predates the opening of the North Atlantic by at least 70 m.y.”) > > [https://www.researchgate.net/publication/235982076\_Iceland\_hotspot\_track](https://www.researchgate.net/publication/235982076_Iceland_hotspot_track) > [@Andy\_L](#): > > Thanks. Learn something new everyday. From the first cite: > [@](#): > > The North American Plate and the Eurasian Plate are moving away from one another at a rate of 10km every million years; **about the same rate as your fingernails grow**. ---
**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:** [February 17, 2019, 8:16pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/17 "2019-02-17T20:16:08Z")
> [@Northern\_Piper](#): > > So was the Pacific once much bigger? Well depending on how you define “The Pacific” it was once all the ocean that was. > [@](#): > > The Pacific Ocean was born 750 million years ago at the breakup of Rodinia, although it is generally called the Panthalassic Ocean until the breakup of Pangea, about 200 million years ago. The oldest Pacific Ocean floor is only around 180 Ma old, with older crust subducted by now. > **[Pacific Ocean](https://en.wikipedia.org/wiki/Pacific_Ocean)** > > Main five oceans division: > Further subdivision: > The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continents of Asia and Australia in the west and the Americas in the east. ---
**Author:** ![DesertDog](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/desertdog/32/11503_2.png) [@DesertDog](https://boards.straightdope.com/u/DesertDog)\ **Post date:** [February 18, 2019, 5:21pm UTC](https://boards.straightdope.com/t/why-no-ring-of-fire-around-the-atlantic/829479/18 "2019-02-18T17:21:37Z")
> [@dtilque](#): > > Nope, sorry. It’s smack dab on the Mid-Atlantic Ridge. Go look at an undersea map of the Atlantic. I remember a photo from last year where a Doper was diving off the coast of Iceland and had his hands touching the two different plates, which I thought was incredibly cool. Certainly put my touching the [Vishnu schist](https://en.wikipedia.org/wiki/Vishnu_Basement_Rocks) when I took a mule to the bottom of Grand Canyon into the shade.