<p>Re: Seamounts vs land based Mountains</p>

<p>Mt Everest is the highest land based mountain at 8,800m above sea level.</p>

<p>Mauna Kea seems the highest Seamount at 10,100m with 4,200m above sea level and therefore about 6,000m below sea level. </p>

<p>A typical Seamount is 1,000 to 4,000m which seems similar to land based mtns.</p>

<p>Somewhat avoiding debate over whether above of below sea-level Mauna Kea still seems the highest Seamount.</p>

<p>Another item of interest is what is the deepest ocean trench and it seems to be the Mariana Trench at -10,994m below sea level.</p>

<p>The Mariana Trench or Marianas Trench is located in the western Pacific Ocean about 200 kilometres (124 mi) east of the Mariana Islands, and has the deepest natural trench in the world. Elevation: -10,994 m.</p>

<p>Greg W   </p>

CC BY-SA 4.0
2019-06-22T15:34:42.477Z
2019-06-22T15:34:42.477Z
Greg W
<p>This answers <em>one</em> of the questions you list, but the <em>shallowest</em> seamount, per <a href="http://en.wikipedia.org/wiki/List_of_submarine_volcanoes">this list on Wikipedia</a> is <a href="http://en.wikipedia.org/wiki/Banua_Wuhu">Banua Wahu</a>, which is 8 meters below the surface, but has risen above the surface and fallen below the surface several times in recorded history.</p>

<p>However, this is definitely <em>not</em> the tallest seamount, standing only 400m high from its base.</p>

<p><strong>Edit</strong><br/>
A larger database by <a href="http://doi.pangaea.de/10.1594/PANGAEA.757562">Yesson, C et al.</a> includes several seamounts that are within 2 meters of the surface.  However, the data does not suggest when the measurements were taken (high tide or low tide), which would have obvious implications.  Also, there are many seamounts within that range (I stopped counting at 100).</p>

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2014-05-07T16:55:19.283Z
Just adding fuel to the fire... :P
Richard
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2014-05-07T16:54:54.700Z
2014-05-07T19:40:55.407Z
2014-05-07T19:40:55.407Z
Richard
<p>According to the <em>Oxford Dictionary of Earth Sciences</em>,</p>

<blockquote>
  <p><strong>seamount</strong> Isolated, submarine mountain rising more than 1000m above the ocean floor. The sharp, crested summits of seamounts are usually 1000-2000m below the ocean surface. Seamounts are of volcanic origin.</p>
</blockquote>

<p>To avoid classifying seamounts by arbitrary sea level (dependent on availability of surface water), the key point is then that seamounts are features of volcanic origin that rise over 1000m above oceanic crust.</p>

<p>The Hawai'i-Emperor seamount chain is of volcanic origin; all of the islands in this chain are seamounts. Mauna Kea only rises 4207m above sea level - but measured from its base on the oceanic plate it is 10100m high, <em>much</em> taller than Mt Everest. Mauna Kea is - pretty conclusively - the highest seamount in the world. The <a href="http://www.whoi.edu/main/topic/seamounts">Woods Hole Oceanographic Institute agrees</a>.</p>

CC BY-SA 3.0
2014-05-07T14:39:31.297Z
"A [seamount](http://en.wikipedia.org/wiki/Seamount) is a mountain rising from the ocean seafloor that does not reach to the water's surface" - Mauna Kea is above sea level.
blunders
CC BY-SA 3.0
2014-05-07T14:42:51.120Z
(1) That's not the definition that the ODES uses, as quoted; (2) if you use the (unsourced) Wikipedia definition the answer is trivially constrained by water depth.
kaberett
CC BY-SA 3.0
2014-05-07T14:44:38.437Z
Hello, thank you for your answer but I don't think that these are the highest ones. For example, in the Indian Ocean at 180 km from the island where I live (Île de la Réunion) there is a seamount called "La Perouse Seamount" that would be at around -50m below the water's surface.
Pop Flamingo
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2014-05-07T14:46:42.227Z
I agree that the definition doesn't give the highest seamounts, rather the typical ones. I quoted the definition to clarify my interpretation of the question.
kaberett
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2014-05-07T14:52:16.423Z
Reread your ODES' definition, it clearly states seamounts are "submarine mountains" - right?
blunders
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2014-05-07T14:53:18.273Z
@blunders http://www.whoi.edu/main/topic/seamounts <-- Wood Hole disagrees. "Submarine" covers a multitude of sins, including "at least in part". Note that if they are defined as submarine then what meets the definition of "seamount" is entirely subject to present sea level, which does not to me seem a very helpful definition.
kaberett
CC BY-SA 3.0
2014-05-07T14:59:57.343Z
Wow, "forget semantics, I'll just dig up a link" - submarine most clearly means beneath the water, and Wood Hole is confused; likely confusing that when a seamount surfaces, it's know as an oceanic island, and it's common for a seamount to become an oceanic island, then revert to being a seamount.
blunders
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2014-05-07T15:00:32.603Z
............ Woods Hole is the *world leader in this field*. They are *the authoritative institution*. I don't know what more you want.
kaberett
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2014-05-07T15:06:08.890Z
@kaberett: ODES does not define submarine, but Oxford Dictionary define submarine as: "[Existing, occurring, done, or used under the surface of the sea.](http://www.oxforddictionaries.com/us/definition/american_english/submarine?q=submarine)" - stand by my statements.
blunders
CC BY-SA 3.0
2014-05-07T15:08:58.277Z
The important point about seamounts *cannot* be that they are *in whole submarine*, though - because the definition is then entirely subject to arbitrary sea level. The key point from that definition, from my perspective - and clearly from WHOI's - is that a seamount is a feature of volcanic origin rising over 1000m from oceanic crust.
kaberett
CC BY-SA 3.0
2014-05-07T15:12:01.787Z
(+1) I didn't realise Mauna Kea was so tall!
Chris Mueller
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2014-05-07T15:23:44.367Z
Called WHOI and they said, the person that wrote that is at sea, so much for being able to nail down a source. So, guess I see no reason why you couldn't list the tallest fully underwater seamount too, which would resolve the issue until WHOI's able to ping the guy on the boat... :-)
blunders
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2014-05-07T15:31:24.557Z
FYI, the poster of the question means "nearest to the sea level" not tallest.
blunders
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2014-05-07T16:34:39.437Z
FYI, the image caption on the Wood Hole page states "A seamount, or **underwater mountain**, on the Artic Ocean seafloor. (NOAA)"
blunders
CC BY-SA 3.0
2014-05-07T17:04:13.257Z
The WHOI page contradicts itself -- it says "**underwater** mountain", and then says it can break the surface (and gives Hawaii as an example). If a mountain's peak is permanently in the air, it's an _island_. If it's awash, it's a _shoal_. If it's permanently under water (barring major sea level changes), it's a seamount or guyout (flat topped, formerly at the surface but has subsided).
Phil Perry
CC BY-SA 3.0
2014-05-07T14:35:16.270Z
2014-05-07T15:14:05.050Z
2014-05-07T15:14:05.050Z
kaberett
<p>I was wandering around some seabed topos yesterday and found a spire at the bottom of the trench that rises from 35,000ft to 8,700, making this discrete and very steep spire about 26,000 feet high. <a href="https://i.sstatic.net/fG9z1.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/fG9z1.jpg" alt="enter image description here" /></a></p>

CC BY-SA 4.0
2022-08-02T19:04:26.293Z
2022-08-02T19:04:26.293Z
Dad
<p>I am wondering what is the tallest fully underwater seamount in the world ? When I say the tallest, I mean the one that is the nearest of the sea level.
<em>EDIT : The highest that I found would be at about 50m below the water's surface do you know any other seamount that would be even higher ?</em></p>

CC BY-SA 3.0
2016-03-11T05:13:30.647Z
@Jim But it isn't a seamount ?
Pop Flamingo
CC BY-SA 3.0
2014-05-07T15:31:35.687Z
@TrevörAnneDenise I'm afraid I don't understand the motivation for knowing which seamount currently most closely approaches the surface without breaking it. This tells you nothing about processes - it's completely dependent on which sea level you pick. Mounts in the Hawai'ian-Emperor chain have been gradually eroded backwards; [Surtsey](http://en.wikipedia.org/wiki/Surtsey#Permanent_island) only became a permanent island in 1964. Sea level isn't a constant. I don't understand why this question is meaningful, as it stands.
kaberett
CC BY-SA 3.0
2014-05-07T15:33:27.553Z
@kaberett Biodiversity depends of the depth, you won't find the same species at -20m, than at -50m, than at -200m and so on...
Pop Flamingo
CC BY-SA 3.0
2014-05-07T15:37:29.667Z
@TrevörAnneDenise Indeed not, but as seamounts are _isolated_ the ability of benthic fauna/flora to reach them is questionable, cf morphological and genetic diversity between separated habitats (the example that springs to mind is trilobites in Scotland + Canada, and the obvious effects of continental rifting). If your question is about biodiversity, (1) can you edit that in, (2) clarify why it doesn't apply to Hawai'i (which covers the whole range of depths...?), and (3) clarify why you are interested in seamounts particulary as an environment? I'd be interested in seeing that explored :-)
kaberett
CC BY-SA 3.0
2014-05-07T15:42:34.377Z
@kaberett Since I am french and not very good at english, I don't know if I understand very precisely what you are telling me but I'll try to answer to your questions. I saw and read many things stating that the seamounts have got a lot of animals on it. I am interested by seamounts because I might soon create a (reduced size) bot+submarine to explore a seamount that is pretty close to the island where I live. I was just surprised to see that it is only -50m below the surface and so I was curious to know if there was any other seamount that would be even closer to the surface.
Pop Flamingo
CC BY-SA 3.0
2014-05-07T15:44:45.417Z
Question is "**How do I find seamounts within [insert-distance] below the surface near [insert-location]?**"
blunders
CC BY-SA 3.0
2014-05-07T17:25:25.250Z
[Seamount Catalog](http://earthref.org/SC/#top) might be of use, though it does not appear to allow a direct query of distance below the surface.
blunders
CC BY-SA 3.0
2014-05-07T22:37:59.123Z
So, did ask more questions, as you might have seen, and a [database of 30000 seaamounts was linked](http://earthscience.stackexchange.com/a/847/284) to; the reasearcher claim it covers 94% of the seamounts. While so far it doesn't appear to cover the depth below sea-level, like the best starting point so far for your question.
blunders
<ocean><oceanography><mountains>
What is the tallest fully underwater seamount in the world?
Pop Flamingo
# What is the tallest fully underwater seamount in the world?

(Asked by: username_0 on 2014-05-07)

I am wondering what is the tallest fully underwater seamount in the world ? When I say the tallest, I mean the one that is the nearest of the sea level.
*EDIT : The highest that I found would be at about 50m below the water's surface do you know any other seamount that would be even higher ?*

**Tags:** ocean, oceanography, mountains

> **Comments:**
> **username_1**: @TrevörAnneDenise I'm afraid I don't understand the motivation for knowing which seamount currently most closely approaches the surface without breaking it. This tells you nothing about processes - it's completely dependent on which sea level you pick. Mounts in the Hawai'ian-Emperor chain have been gradually eroded backwards; [Surtsey](http://en.wikipedia.org/wiki/Surtsey#Permanent_island) only became a permanent island in 1964. Sea level isn't a constant. I don't understand why this question is meaningful, as it stands.  
> **username_0**: @username_1 Biodiversity depends of the depth, you won't find the same species at -20m, than at -50m, than at -200m and so on...  
> **username_1**: @TrevörAnneDenise Indeed not, but as seamounts are _isolated_ the ability of benthic fauna/flora to reach them is questionable, cf morphological and genetic diversity between separated habitats (the example that springs to mind is trilobites in Scotland + Canada, and the obvious effects of continental rifting). If your question is about biodiversity, (1) can you edit that in, (2) clarify why it doesn't apply to Hawai'i (which covers the whole range of depths...?), and (3) clarify why you are interested in seamounts particulary as an environment? I'd be interested in seeing that explored :-)  
> **username_0**: @username_1 Since I am french and not very good at english, I don't know if I understand very precisely what you are telling me but I'll try to answer to your questions. I saw and read many things stating that the seamounts have got a lot of animals on it. I am interested by seamounts because I might soon create a (reduced size) bot+submarine to explore a seamount that is pretty close to the island where I live. I was just surprised to see that it is only -50m below the surface and so I was curious to know if there was any other seamount that would be even closer to the surface.  
> **username_2**: Question is "**How do I find seamounts within [insert-distance] below the surface near [insert-location]?**"  
> **username_2**: [Seamount Catalog](http://earthref.org/SC/#top) might be of use, though it does not appear to allow a direct query of distance below the surface.  
> **username_2**: So, did ask more questions, as you might have seen, and a [database of 30000 seaamounts was linked](http://earthscience.stackexchange.com/a/847/284) to; the reasearcher claim it covers 94% of the seamounts. While so far it doesn't appear to cover the depth below sea-level, like the best starting point so far for your question.  
> **username_0**: @Jim But it isn't a seamount ?  

---

## 4 answers

### Answer by username_3 on 2019-06-22. Score: -1 | Accepted answer

Re: Seamounts vs land based Mountains

Mt Everest is the highest land based mountain at 8,800m above sea level.

Mauna Kea seems the highest Seamount at 10,100m with 4,200m above sea level and therefore about 6,000m below sea level.

A typical Seamount is 1,000 to 4,000m which seems similar to land based mtns.

Somewhat avoiding debate over whether above of below sea-level Mauna Kea still seems the highest Seamount.

Another item of interest is what is the deepest ocean trench and it seems to be the Mariana Trench at -10,994m below sea level.

The Mariana Trench or Marianas Trench is located in the western Pacific Ocean about 200 kilometres (124 mi) east of the Mariana Islands, and has the deepest natural trench in the world. Elevation: -10,994 m.

username_3


---

### Answer by username_4 on 2014-05-07. Score: 12

This answers *one* of the questions you list, but the *shallowest* seamount, per [this list on Wikipedia](http://en.wikipedia.org/wiki/List_of_submarine_volcanoes) is [Banua Wahu](http://en.wikipedia.org/wiki/Banua_Wuhu), which is 8 meters below the surface, but has risen above the surface and fallen below the surface several times in recorded history.

However, this is definitely *not* the tallest seamount, standing only 400m high from its base.

**Edit**  
A larger database by [Yesson, C et al.](http://doi.pangaea.de/10.1594/PANGAEA.757562) includes several seamounts that are within 2 meters of the surface. However, the data does not suggest when the measurements were taken (high tide or low tide), which would have obvious implications. Also, there are many seamounts within that range (I stopped counting at 100).

> **Comments:**
> **username_4**: Just adding fuel to the fire... :P  

---

### Answer by username_1 on 2014-05-07. Score: 12

According to the *Oxford Dictionary of Earth Sciences*,

> **seamount** Isolated, submarine mountain rising more than 1000m above the ocean floor. The sharp, crested summits of seamounts are usually 1000-2000m below the ocean surface. Seamounts are of volcanic origin.

To avoid classifying seamounts by arbitrary sea level (dependent on availability of surface water), the key point is then that seamounts are features of volcanic origin that rise over 1000m above oceanic crust.

The Hawai'i-Emperor seamount chain is of volcanic origin; all of the islands in this chain are seamounts. Mauna Kea only rises 4207m above sea level - but measured from its base on the oceanic plate it is 10100m high, *much* taller than Mt Everest. Mauna Kea is - pretty conclusively - the highest seamount in the world. The [Woods Hole Oceanographic Institute agrees](http://www.whoi.edu/main/topic/seamounts).

> **Comments:**
> **username_2**: "A [seamount](http://en.wikipedia.org/wiki/Seamount) is a mountain rising from the ocean seafloor that does not reach to the water's surface" - Mauna Kea is above sea level.  
> **username_1**: (1) That's not the definition that the ODES uses, as quoted; (2) if you use the (unsourced) Wikipedia definition the answer is trivially constrained by water depth.  
> **username_0**: Hello, thank you for your answer but I don't think that these are the highest ones. For example, in the Indian Ocean at 180 km from the island where I live (Île de la Réunion) there is a seamount called "La Perouse Seamount" that would be at around -50m below the water's surface.  
> **username_1**: I agree that the definition doesn't give the highest seamounts, rather the typical ones. I quoted the definition to clarify my interpretation of the question.  
> **username_2**: Reread your ODES' definition, it clearly states seamounts are "submarine mountains" - right?  
> **username_1**: @username_2 http://www.whoi.edu/main/topic/seamounts <-- Wood Hole disagrees. "Submarine" covers a multitude of sins, including "at least in part". Note that if they are defined as submarine then what meets the definition of "seamount" is entirely subject to present sea level, which does not to me seem a very helpful definition.  
> **username_2**: Wow, "forget semantics, I'll just dig up a link" - submarine most clearly means beneath the water, and Wood Hole is confused; likely confusing that when a seamount surfaces, it's know as an oceanic island, and it's common for a seamount to become an oceanic island, then revert to being a seamount.  
> **username_1**: ............ Woods Hole is the *world leader in this field*. They are *the authoritative institution*. I don't know what more you want.  
> **username_2**: @username_1: ODES does not define submarine, but Oxford Dictionary define submarine as: "[Existing, occurring, done, or used under the surface of the sea.](http://www.oxforddictionaries.com/us/definition/american_english/submarine?q=submarine)" - stand by my statements.  
> **username_1**: The important point about seamounts *cannot* be that they are *in whole submarine*, though - because the definition is then entirely subject to arbitrary sea level. The key point from that definition, from my perspective - and clearly from WHOI's - is that a seamount is a feature of volcanic origin rising over 1000m from oceanic crust.  
> **username_5**: (+1) I didn't realise Mauna Kea was so tall!  
> **username_2**: Called WHOI and they said, the person that wrote that is at sea, so much for being able to nail down a source. So, guess I see no reason why you couldn't list the tallest fully underwater seamount too, which would resolve the issue until WHOI's able to ping the guy on the boat... :-)  
> **username_2**: FYI, the poster of the question means "nearest to the sea level" not tallest.  
> **username_2**: FYI, the image caption on the Wood Hole page states "A seamount, or **underwater mountain**, on the Artic Ocean seafloor. (NOAA)"  
> **username_6**: The WHOI page contradicts itself -- it says "**underwater** mountain", and then says it can break the surface (and gives Hawaii as an example). If a mountain's peak is permanently in the air, it's an _island_. If it's awash, it's a _shoal_. If it's permanently under water (barring major sea level changes), it's a seamount or guyout (flat topped, formerly at the surface but has subsided).  

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### Answer by username_7 on 2022-08-02. Score: 1

I was wandering around some seabed topos yesterday and found a spire at the bottom of the trench that rises from 35,000ft to 8,700, making this discrete and very steep spire about 26,000 feet high. [![enter image description here](https://i.sstatic.net/fG9z1.jpg)](https://i.sstatic.net/fG9z1.jpg)


---

