# Talk:Mariana Trench

## Pressure ?

Surely under pressure water is squeezed tighter. So 95 litres at the taking up the same space as 100, surely 100 litres would be condensed to take up the same space as 95 litres would on the surface. Just to clarify, saying it a different way i guess... — Preceding unsigned comment added by 101.113.37.52 (talk) 13:15, 23 August 2013 (UTC)

Normally, that would be P = ρ g h. Using ρ = 1000 kg/m³, g = 9.80665 m/s² and h = 10,923 m, I get 107.12 MPa (15,536 psi). So why does the article say « 108.6 MPa (15,931 psi) » (which is incorrect anyway since 108.6 MPa = 15751 psi)? Water being ever so slightly compressible means may explain the difference, but it seems a large one...

Urhixidur 00:04, 2005 Feb 10 (UTC)

Seawater has a density higher than 1000 kg/m^3. Salinity varies, but at the surface, it's about 1020-1030 kg/m^3 according to hypertextbook. Working backwards, assuming the depth and pressure measurements are correct, the average density over the depth of the water column would be ~1013 kg/m^3. A minor considering: the atmosphere exerts 1 atm (14.7 psi) of pressure in addition to the weight of the water.

--Daniellwu 00:27, 10 Feb 2005 (UTC)

Ah, that makes sense. Should have thought of that!
Urhixidur 05:07, 2005 Mar 23 (UTC)

## Plural

In French the name is definitely plural; should it be in English too? Aren't the islands the Marianas rather than the Mariana (like the current entry says)? I suggest we look up the Britannica on the one hand, and the UN toponymy committee on the other. Right now I'm off to bed.

Urhixidur 05:06, 2005 Mar 23 (UTC)

Whatever the islands are called, the oceanic trench seems to be called both "Mariana Trench" and "Marianas Trench". However, "Mariana Trench" seems to be a bit more common based on Google hit counts. Usgs.gov seems to use both: [1] [2], but again "Mariana Trench" is a bit more common. -- Curps 05:51, 23 Mar 2005 (UTC)
The Britannica is quite clear: both the islands and the trench are singular (they are named after Mariana of Austria). The mproblem I had initially was with the Google method: Google polling is a very poor way of deciding these kinds of things, for several reasons. Internet page counts do not reflect accurately usage in the widest context, because of severe population biases. Google counts also do not discriminate between pages which are semi-automatic copies of each other (several web servers pump content from Wikipedia, for example), and the aforementioned population biases are also reflected in the way errors (as well as corrections and facts) spread from page to page.
To summarise, an overwhelming Google "vote" in favour of one of several alternatives should be counted only as one corroborating, weak element of proof.
Urhixidur 14:36, 2005 Mar 23 (UTC)
You are right that Google hit count is only one element to take into consideration, although an important one. Brittanica usage is also only one element to take into consideration. I would have hoped that the scientists who actually study oceanic trenches would have a clear preference, but as usgs.gov usage shows, they are also divided. All in all, though, I think we can leave it at Mariana Trench. -- Curps 20:08, 23 Mar 2005 (UTC)
Hmmmmm. Well, first of all, just because a word (especially a name) ends in "s" does not mean it is necessarily plural. But we all know that, I'm sure. Anyway, I just wanted to say that I have never before this seen the name "Mariana Trench"; I have always seen it rendered as "Marianas Trench". 68.218.243.195 20:20, 28 October 2007 (UTC)

I think the confusion arises from the fact that there is more than one Island in the Mariana chain, and so they are collectively known as the Marianas. Any book on Naval activity in the Pacific during WWII refers to the Marianas collectively, and any individual Island is referred to by its name (Guam, Tinian, Saipan, etc). North Americans tend to hang the possessive "S" on just about anything, so it does not come as a surprise that the trench itself is commonly, and incorrectly, known as the Marianas Trench. Until today I did not know any different.

As an aside, I am wondering which ships were sunk into the Mariana Trench during Naval action in WWII....what a long way down. I cannot imagine that any vessel was not flattened by the pressure at the bottom. Jeff Knorek, Bear River NS 15 January 2012. — Preceding unsigned comment added by Jeff Knorek (talkcontribs) 04:05, 15 January 2012 (UTC)

## Broken image?

The picture seems broken, to me. Does anyone else not see the image? Wadsworth 22:46, 19 April 2006 (UTC)

## The Abyss?

The Movie: The Abyss took place near the Cayman Trench, not the Mariana Trench.

Please sign and date your contributions and format them properly. I have changed the Wikilinked phrase you used from "The Abyss took" to "The Abyss". DQweny (talk) 23:58, 15 October 2009 (UTC)

## The Band?

What about the rock band from vancouver, british columbia? anyone feel like at least creating a stub for this talented and catchy group? check out http://www.myspace.com/marianastrench

not unless they are notable. It is irrelevant here anyway.
Also reverted some old vandalism at the page top. Vsmith 03:38, 27 July 2006 (UTC)

## Other Languages

The dutch page notes that its 11,035 meters deep. Also the German page notes 11,035. The Scandinavian pages notes that's 10,911 meters deep. The English page notes that is 10,924 meters deep but on the main stub Ocean Trench notes also the 10,911 meters. But if you go to http://www.marianatrench.com/mariana_trench-nautical_measurements.htm it notes that deepest point 11,033 meters is. In my opion they don't know exactly how deep the trench is, but 100+ meters (1,1%) is a large difference.

## "recent"?

> In the recent Transformers movie, the remains of the defeated Decepticons are dumped into the Mariana Trench.

I think terms such as 'recent' need to be avoided or defined.

I added the "Measurement and Study" header. The article seems more organized and is easier to browse with it. Benastan (talk) 18:39, 23 February 2008 (UTC)

## Width?

I know this article probably only serves to let people seeking information about Earth's extreme geography ooh and aww at the depth, but what's the width of the trench? Is it just a giant canyon with consistent width, or is it like a giant inverted triangle, with the two sides converging at the bottom? 24.3.14.157 (talk) 15:10, 4 August 2008 (UTC)

## References

Reference No. 2 points to the same URL as referrence No. 4 (I couldn't find a way to edit the references, so I mention it here instead). —Preceding unsigned comment added by Henrikthiil (talkcontribs) 01:01, 5 November 2008 (UTC)

## Creation paragraph

I am sure the content is acceptable, but it really needs to be rewritten in a more fitting style. 86.13.113.184 (talk) 23:48, 9 May 2009 (UTC)

## Picture gallery

Could I suggest a picture gallery consisting of photos taken by oceanographic survey vessels? Considering this is the deepest point on Earth, a gallery consisting of photos taken there may be of some interest. Currently this article doesn't have ANY pictures of the actual location. --Pstanton (talk) 00:48, 6 October 2009 (UTC)

## Problems with descents section

There needs to be a lot more information on what was found during the various descents, and if possible a photograph of the trench floor.

Also, the description of the UAE-financed descent is not NPOV and needs to be rewritten, and lacks references. I have added a references tag. If no one supplies a reference and rewrites that paragraph within the next seven days, I'm just going to delete it. DQweny (talk) 00:02, 16 October 2009 (UTC)

User:Vsmith just deleted it. DQweny (talk) 15:57, 18 October 2009 (UTC)
Yup. It can be re-added if sourced and re-written to avoid puffery. Vsmith (talk) 16:13, 18 October 2009 (UTC)

"A final fourth decent was made on August 2nd 2010 by Mathilde Eldridge, who reached the bottom in the deep sea vessel, the Eliza Deepthaw."

This was edited at 10.16 and I cannot find any information or news pertaining to such claim; I am beginning to think this is a false claim. —Preceding unsigned comment added by 171.159.64.10 (talk) 16:22, 2 August 2010 (UTC)

Silliness removed, thanks. Mikenorton (talk) 17:08, 2 August 2010 (UTC)

Question: Shouldn't this section be corrected to include a 3rd unmanned descent in 2008, by the ABISMO vehicle built by the Japan Agency for Marine-Earth Science and Technology? See reference: http://www.jamstec.go.jp/e/about/press_release/20080616/ Newsbeagle (talk) 22:27, 13 March 2012 (UTC)

## Noclear issues

Does any one have issues with the new section?Slatersteven (talk) 14:40, 18 September 2010 (UTC)

I think you mean "nuclear" issues, not "noclear". There is an ongoing discussion at Talk:Challenger Deep#Removed possible nuclear waste disposal site section, where the section has appeared first before it was copied here with little change. Since the issues are precisely the same, I don't think forking the discussion is a good idea. Hans Adler 14:54, 18 September 2010 (UTC)
Its a pun.Slatersteven (talk) 14:55, 18 September 2010 (UTC)
Then don't try to explain it, as that will probably make it worse. Hans Adler 15:00, 18 September 2010 (UTC)

## Merge Challenger Deep here

I don't see these two subjects as sufficiently distinct to merit separate articles. What do others think? --John (talk) 18:38, 19 September 2010 (UTC)

The material was originally removed from Challenger Deep because the sources did not support it. After discussion on the talk page and on the OR noticeboard, the editor(s) arguing for inclusion fail to abide by the most basic, fundamental policies and guidelines. Further research shows that this topic is being given undue weight, as it does not appear to reflect its representation in reliable sources about Mariana and Challenger. Furthermore, the editor who keeps adding it appears to be pushing a POV. Until the concerns raised on the Challenger Deep talk page and the OR board are directly addressed (so far they remain ignored) the material should not be here. Viriditas (talk) 23:52, 19 September 2010 (UTC)
You misunderstood me. I am arguing that these two subjects are not sufficiently distinct as to merit two articles. I made no statement about what content I would wish to see in the merged article. That would remain to be decided. Let's agree the merge first (or not, if there are compelling reasons I have not seen to keep two articles). --John (talk) 00:14, 20 September 2010 (UTC)
No, I think you misundertood me. This content is highly disputed, and is currently the outstanding subject of an open talk page discussion, an OR noticeboard report, and an ANI incident. After researching this subject and looking at how Wikipedia currently handles it, this type of material appears to be a subset of our article on radioactive waste, not oceanic trenches. Various proposals have been put forward to dump nuclear waste in many locations, and it's not really appropriate to add speculative proposals to every subject, such as the Sun, Moon, Antarctica, seabed, etc. On Wikipedia, we generally approach this subject by focusing on what significant reliable sources on the topic say, and if they don't say much, we try and find the right fit for the material, otherwise we delete it. Speculative proposals as to dumping nuclear waste have been made regarding many locations on the planet and outside of it. It isn't feasible to add this kind of speculation to location articles. Best practice is to find an article like radioactive waste or a subarticle within that scope, and add it there. Viriditas (talk) 00:23, 20 September 2010 (UTC)
You say "this content", but I haven't added any content, merely a tag. --John (talk) 00:56, 20 September 2010 (UTC)
The merge tag refers to the content in question, does it not? Adding a merge tag for disputed content is not helpful. Viriditas (talk) 01:01, 20 September 2010 (UTC)
No, the merge tag merely refers to the articles. It makes no supposition about what the content of the resulting merged article would be. You can look at it as solving the problem once being preferable to solving it twice if that helps you to see where I am coming from on this. --John (talk) 01:08, 20 September 2010 (UTC)
Sorry, John, but maintenance tags do not exist in a vacuum. Nothing needs merging. Please follow the discussion on Talk:Challenger Deep, the OR noticeboard and the ANI report. The subject is already covered in our article on high-level radioactive waste management and is pure WP:SPECULATION not represented by significant, current sources on the subject. Viriditas (talk) 01:14, 20 September 2010 (UTC)

────────────────────────────────────────────────────────────────────────────────────────────────────Well, we can go to AfD if necessary, but meantime let's just focus on why the two subjects are independently notable enough to require their own articles. Arguments on that, not on their current content, please. --John (talk) 02:12, 20 September 2010 (UTC)

This page should be merged with Challenger Deep mtthwbckmn (talk) 12:57, 20 September 2010 (UCT)
• Oppose Merge. Challenger Deep is a particular feature of the Trench, and is a distinct topic. It should no more be merged with this article than Mount Everest should be merged with Himalayas. TJRC (talk) 20:10, 20 September 2010 (UTC)
• Vote Change. After additional consideration, I think it should remain separate as well. After all, it's not just Mount Everest that has its own article, but K2 as well. Challenger Deep has received a fairly large amount of independent coverage, enough I think to warrant it remaining separate. Fell Gleamingtalk 20:30, 20 September 2010 (UTC)
• Oppose merge. Challenger deep appears to be notable in and of itself. Cla68 (talk) 01:39, 21 September 2010 (UTC)

## Vityaz-1 Deep?

It reaches a maximum-known depth of about 11.03 kilometres (6.85 mi) at the Vityaz-1 Deep[citation needed] and about 10.91 kilometres (6.78 mi) at the Challenger Deep...

Vityaz being the name of the ship making the recording in 1957. I can not find any reference to this particular region as 'Vityaz-1 Deep'. Challenger Deep lists the formation as 'Mariana Hollow' and the National Geographic citation cites the 11,034 meter depth as the deepest for the Challenger Deep. From this it appears that the 'Vityaz-1 Deep' is not a separate feature from the 'Challenger Deep' but rather a specific measurement of a region of the 'Challenger Deep'. WhiskeyedJack (talk) 18:42, 7 February 2011 (UTC)

Removed reference to 'Vityaz-1 Deep' and attempted to clarify intro. WhiskeyedJack (talk) 18:30, 14 February 2011 (UTC)

## Depth: slightly less or slightly more than 12 km?

Yes it is.. Its not true I have been there and as per my knowledge its near by 12 km. The German Wikipedia has the information that "Marianengraben's" depth is 11.034 m and that 10.912 m was the lowest point reached by human, so this should be examined and corrected in this article. --Romanm 23:57, 8 Jul 2004 (UTC)

Article Challenger Deep indicates 10,911 m (and is said verified by Guinness) and here it is 10,912 m. Wich one is right? [[User:Vrykolaka|Reply to Vrykolaka]] 01:35, 24 Oct 2004 (UTC)

see Talk:Challenger Deep for more info on depths Cavebear42 05:41, 10 Feb 2005 (UTC)

Further to these, the opening statements in this article contradict themselves. If "It is currently estimated to be up to 10,971 m (35,994 ft) deep" then how can it be DEEPER then that estimate given that the article then states "It reaches a maximum-known depth of about 11.03 kilometres (6.85 mi) at the Vityaz-1 Deep"? —Preceding unsigned comment added by 87.113.254.237 (talk) 07:18, 14 February 2011 (UTC)

Fixed the contradictory statements, check out my comment on the Vityaz-1 Deep? below. WhiskeyedJack (talk) 18:37, 14 February 2011 (UTC)

Also, then, you should change 2,076 to 2,062 in the first paragraph in order to make the math work. If you hold to the figures you present in your opening statements, (8,848m for the mountain and 10,910m for the trench), the resulting span of 19,758m is 2,062 units greater than twice 8,848. Or, stated more simply, the difference between 10,910 and 8,848 is 2,062, not 2,076. 98.237.251.160 (talk) 15:46, 17 August 2011 (UTC)

## Mariana Islands

At the moment we state:

"The movement of these plates is also responsible for the formation of the Mariana Islands."

Unless I'm missing something it's the volcanism, associated with the melting of the asthenosphere due to fluid escape from the subducting slab, which creates the islands rather than movement. I'll come back and change it if no-one has any objections. JJJJS (talk) 00:07, 28 April 2011 (UTC)

The movement of plates is what presents fresh water to the hot region, which causes the continued volcanism. Stop the plate movement and the volcanism would stop. In that sense, the movement of the plates, which carries the water to the heat, causes the volcanism and the islands. Come on, man, if I said that the movement of the plates causes earthquakes, would you object again and say "No, it's slipping of faults that causes earthquakes.."? SBHarris 21:17, 15 November 2011 (UTC)

## Mariana hollow

If the Soviets measured this deep (11,033 m (36,198 ft)), why does the lead of this article mention 10971 m? 81.68.255.36 (talk) 21:06, 15 June 2011 (UTC)

Because there's a difference between what you measure directly vs. indirectly. The very deepest pocket probably is 11,033 m. But none of the direct descents (one bathyscape and two robots) happened to exactly descend at that point, and consequently, all of them got readings about 60 m shallower, which is probably more representive of the depth of most of the trench floor. SBHarris 21:10, 15 November 2011 (UTC)

## cameron planning to film here for avatar 2

http://en.wikipedia.org/wiki/Avatar_2#Sequels — Preceding unsigned comment added by 67.81.199.45 (talk) 20:43, 15 November 2011 (UTC)

## US monument?

Just heard on Jeopardy that this is somehow a US monument.  If so, it doesn't seem to be mentioned in the article.  Unscintillating (talk) 00:57, 10 January 2012 (UTC)

thats because its not mentioned. for now, ive added it as a "see also" link. should be incorporated into the body of the article.Mercurywoodrose (talk) 07:24, 3 February 2012 (UTC)
Good job.  Thanks, Unscintillating (talk) 00:03, 4 February 2012 (UTC)

## Everest

The sentence in the opening section which says If Mount Everest, the highest mountain on Earth at 8,848 metres (29,029 ft), was set in the deepest part of the Mariana Trench, there would be 2,060 metres (6,760 ft) of water left above it doesn't seem very encyclopaedic and treats the reader as stupid (along the lines of American media saying things like London, England and Switzerland roughly the size of New Hampshire). Any intelligent reader can easily know this by the simple calculation of the trench's depth and the height of Everest. Don't treat all Wikipedia readers as morons.--ЗAНИA talk WB talk] 11:24, 23 February 2012 (UTC)

I agree and have never liked it. Also there is the problem of how high IS Everest, anyway? It's measured from mean sea level but nobody looks at it like that. It rises about 12,000 above the Himalyan plain. Denali, as seen by the average person looking at it, is twice as "big." These are all useless comparisons. I'm going to be BOLD and remove it having found somebody else who doesn't like it. SBHarris 06:45, 25 February 2012 (UTC)
I think this is a writing device called a contrast.  Contrast (linguistics) and Contrast (literary) are related.  This particular contrast IMO provides context meaning.  One argument appears to be that this contrast is wikt:blasé ("Unimpressed with something because of over-familiarity") to those familiar with the topic, and that those without such common knowledge are "morons".  IMO the fact that some readers of an article will already know a well-known contrast about a topic is not a reason to remove such contrast from the article.  The issue of how tall is Everest, a quick look at the Mount Everest article shows that there is no dispute regarding the height of Everest.  The first reported height in 1856 was 29,002 ft, and the current accepted height is 29,029 ft.  Unscintillating (talk) 15:11, 25 February 2012 (UTC)

## Timeline for the HMRG Deep discovery

The article lists it as happening in 2003, but when going to the article on the HMRG Deep it's cited as being discovered in 1997. following up on the source cited from that article, it seems it was discovered between 1997 and 2001, so the date here should probably change. — Preceding unsigned comment added by 152.26.239.50 (talk) 18:17, 24 February 2012 (UTC)

There were two cruises, one in 1997 and another in 2001. From what I can tell, it was the later cruise that mapped the area, but that's a bit ORish. I think that it's better to use the words of the BBC report 'between 1997 and 2001', thanks for spotting that - I'll make the change. Mikenorton (talk) 20:31, 24 February 2012 (UTC)

## What about aquatic life in the Trench?

It would be useful to have a section on aquatic life in the Trench. There is a one line mention in the Marine biology entry, but it might be useful to have more. Jackvinson (talk) 14:56, 14 March 2012 (UTC)

I have added the discovery of Xenophyophores and mentioned tiny organisms in the mud samples. More on this topic could still be added and compiled into a fauna section. The geological details could also be fleshed out with some much needed references. - Shiftchange (talk) 11:14, 23 March 2012 (UTC)

Shiftchange, I don't understand what this "sentence" means. It's not even a complete sentence. "Amongst many other living organisms, some gigantic single-celled amoebas with a size of more than 4 inches (10 centimeters), belonging to the class of xenophyophores" That's it? What about the xenophyophores? Were you trying to say that they were discovered in the trench? — Preceding unsigned comment added by 97.112.225.97 (talk) 16:25, 13 April 2012 (UTC)

What I did say in edit was that the xenophyophores were discovered at a record depth in the trench. It may of been altered by others since. - Shiftchange (talk) 23:41, 13 April 2012 (UTC)

Finding microbes in rocks off north America probably does not belong in the lead section of this article. If it's mentioned at all, it should be in the section on Life. I'm removing it for now . . . Elriana (talk) 17:46, 27 February 2014 (UTC)

In the J Cameron section, only sponsor cited is National Geographic. Rolex, too, sponsored. Rolex's current home page opens with their involvement: http://www.rolex.com/en#/home#deepsea-challenge

98.164.238.217 (talk) 15:04, 31 March 2012 (UTC)

Resolved. Fanyavizuri (talk) 09:33, 1 April 2012 (UTC)

Added info about James Cameron's descent. Also cited source (Pacific Daily News). Sprinkler21 (talk) 16:43, 20 March 2012 (UTC)Sprinkler21

James Cameron is Canadian, not American. — Preceding unsigned comment added by 174.6.213.135 (talk) 00:38, 26 March 2012 (UTC)

^^Truth. — Preceding unsigned comment added by 93.133.119.47 (talk) 01:02, 26 March 2012 (UTC)

The article cites giant amoebas found in the "fourth expedition" (reading above, that would be Cameron on March 25th 2012), but the cited source points to an article dated July 2011. Can somebody verify and fix it? 64.60.141.114 (talk) 01:42, 27 March 2012 (UTC)

Good catch. Corrected. --Silvio1973 (talk) 13:01, 27 March 2012 (UTC)

## oblate spheroid

Since this page is protected, can someone add a refrence to the earth being an oblate spheroid (there is a wikipedia entry of the same name) in the opening? Currently the article simply says the earth is not a perfect sphere.

## Edit request on 29 April 2012

The sonar system uses phase and amplitude bottom detection, with an accuracy of better than 0.2% of water depth across the entire swath (implying the depth figure is accurate to less than ± 11 metres).

Should be changed to:

The sonar system uses phase and amplitude bottom detection, with an accuracy of better than 0.2% of water depth across the entire swath (implying the depth figure is accurate to less than ± 22 metres).

Simple mathematics really, and it is also what the currently marked sources state.

213.66.94.124 (talk) 07:54, 29 April 2012 (UTC)

• 0.2% of the depth seems to be 21.94m to me, so I made the change, if that is not the proper way to calculate please feel free to fix it, as my science related math skills are a bit rusty. Monty845 05:21, 2 May 2012 (UTC)

## Edit request on 28 May 2012

Under the listing Mariana Trench is the paragraph headlined Measurement the reference to "Tiefenkarte des Grossen Oceans by Petermann should be changed to read "Ozeans" which is the proper German spelling.

Thanks

Ray Martinez aka ammochief

Ammochief (talk) 22:06, 28 May 2012 (UTC)

Done. SBHarris 23:04, 28 May 2012 (UTC)

## Consideration for inclusion

Home port, Qingdao, Shandong province, China welcomes back Jiaolong submersible. Jiaolong returned in glory from a six-week mission to its home port on Monday (16 July 2012) and received new orders for another research dive. The submersible reached a record depth of 7,062 meters in June in the Mariana Trench in the western Pacific Ocean Return from the ocean deepShieldwolf (talk) 14:20, 17 July 2012 (UTC)

It was only a record depth for that submersible, so I don;t think that it should be included. Mikenorton (talk) 17:33, 17 July 2012 (UTC)
Agree. They could have done 7 km in a lot of places, and didn't need the nearly 11 km deep Mariana Trench to do it. SBHarris 17:51, 17 July 2012 (UTC)

"At the bottom of the trench, where the plates meet, the water column above exerts a pressure of 1,086 bars (15,750 psi)..."

You cannot just say "the plates"! You have not mentioned anything about plates prior to this sentence, so many will not know what on earth you are talking about - dinner plates, home plates, license plates... Yes, some will know that you are referring to tectonic plates, specifically the Pacific and Philippine, but this is still an unforgiveable error. No wonder people chuckle at the mention of WP. Colbyhawkins (talk) 15:47, 6 December 2012 (UTC)Colbyhawkins

WP:Sofixit ... rather than gripe. Aw well, fixed ... please forgive :) Vsmith (talk) 16:06, 6 December 2012 (UTC)

I am not qualified to fix this article - if I were, I wouldn't have consulted WP to start with. I read a few more paragraphs - loads of issues. Here are a few:

"Name

The Mariana Islands were claimed by Spain in 1668. Spain established a colony there, and gave the islands the official title of Las Marianas in honor of Spanish Queen Mariana of Austria, widow of Philip IV of Spain. The islands are part of the island arc that is formed on the over-riding plate, the Mariana Plate, on the western side of the trench. The Pacific plate is being subducted under the islands, forming the trench."

"Because the Pacific plate is the largest of all the tectonic plates on Earth, crustal material at its western edge has had a long time since formation (up to 170 million years) to compact and become very dense;"

There has been no causal relationship established between size and age of plates. Therefore, this sentence is illogical.

"The movement of these plates is also indirectly responsible for the formation of the Mariana Islands (which are caused by volcanism as a result of subduction of water trapped in minerals)."

This sentence is very unclear (how can water cause a volcano?). I would sub for the parenthetical:

(which are caused by volcanism resulting from a process described here) and link to a fairly clear explanation in the third paragraph of the General Description of the Subduction WP article.

That's all I have time for. BTW, my first and last experience attempting to edit a WP article directly was an exercise in frustration. Never again. Colbyhawkins (talk) 18:16, 6 December 2012 (UTC)

## Please Review the deepest point

The deepest point is 11.03 or 11,03 Km? or m? Check puntuation Systems — Preceding unsigned comment added by Dennis6492 (talkcontribs) 04:40, 26 December 2012 (UTC)

## Edit request on 21 January 2013

in the first paragraph the depth of the trench is measured in kilometers while the correct measuring is meters. see the other language editions of wikipedia or just use common sense: radius of earth is in average 6.8k kilometers, a trench with 11k kilometers is not possible. 80.109.116.53 (talk) 13:34, 21 January 2013 (UTC)

The article doesn't state the depth as 11k kilometers (11 kilo-kilometers); it says it's 11 kilometers, which is perfectly possible on an Earth with a radius of ~6800 kilometers. -Nathan Johnson (talk) 15:19, 21 January 2013 (UTC)

## Edit request on 25 June 2013

There is a typo at the beginning that states the depth of the trench is nearly 12,000 km deep. This should be meters.

150.226.95.18 (talk) 20:59, 25 June 2013 (UTC) Don't see it. It currently states: depth of 10.911 km (10,911 ± 40 m) or 6.831 mi (36,069 ± 131 ft) that is just shy of 11 km. Vsmith (talk) 21:34, 25 June 2013 (UTC)

## Semi-protected edit request on 7 April 2014

At this pressure the density of water is increased by 4.96%, making 95 litres of water under the pressure of the Challenger Deep contain the same mass as 100 litres at the surface. The temperature at the bottom is 1 to 4 °C.[4]

This is incorrect. Mass does not change as pressure increases, rather volume decreases and density increases. Source: Law of Conservation of Mass. 172.250.153.72 (talk) 18:58, 7 April 2014 (UTC)

Mass doesn't change, but volume does. Vsmith (talk) 19:03, 7 April 2014 (UTC)
As density increases, the same mass of water takes up less volume. This statement does not imply that the mass changes. Elriana (talk) 21:37, 8 April 2014 (UTC)

## Semi-protected edit request on 9 April 2014

In the first paragraph 10,911 km is around 36,069,000 feet, not 36,069. 78.158.133.53 (talk) 23:13, 9 April 2014 (UTC)

Look again, it says 10.911 km - not 10,911 km. Vsmith (talk) 23:31, 9 April 2014 (UTC)

## Semi-protected edit request on 17 May 2014

The first sentence of the "Life" subsection says:

• "...living creatures such as a sole or flounder about..."

• version 1: "...living creatures such as a flatfish about..."

or

• version 2: "... living creatures such as a flatfish resembling a small halibut or sole about..."

Reason: The mystery flatfish they observed has not been called a flounder. It has been said to resemble a sole (see current reference for sentence) and elsewhere (BBC interview with Don Walsh @ 2.55-3.00) it has been called "flatfish like a small halibut or sole". From this it is quite clear that they don't know what it was, except that it was a flatfish. For this reason I think the most accurate would be to simply leave it at "flatfish" (version 1 above), but if people prefer the more specific you can use version 2 (remember to also add BBC reference then). Regardless, calling it something (flounder) that it hasn't been called is arguably WP:OR. 62.107.194.81 (talk) 12:35, 17 May 2014 (UTC)

Done{{U|Technical 13}} (tec) 13:31, 17 May 2014 (UTC)
Thanks. 62.107.194.81 (talk) 23:02, 17 May 2014 (UTC)

## Semi-protected edit request on 8 June 2014

Kba240 (talk) 15:19, 8 June 2014 (UTC)

Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format. NiciVampireHeart 15:30, 8 June 2014 (UTC)

## Is 'known' necessary to qualify 'deepest'

In a recent edit (since reverted) the statement that the Mariana Trench is the deepest part of the world's oceans has been qualified by the addition of 'known'. We really do know how deep the deepest bits of the ocean our these days. Scientific papers are unequivocal e.g. New organic-walled Foraminifera (Protista) from the ocean's deepest point, the Challenger Deep (western Pacific Ocean), Variable microstructure of peridotite samples from the southern Mariana Trench: Evidence of a complex tectonic evolution - see abstract, so I think we can be as well. Mikenorton (talk) 22:58, 3 February 2015 (UTC)

• I agree with Mikenorton. We currently know the water depths everywhere on earth to within a reasonable margin of error (exact uncertainty varies with the instruments used in a particular area and whether there is sea ice involved). The deepest few trenches have all been mapped with multibeam echosounders (I checked), and there is no place on earth where the depth on our maps (e.g., ETOPO2 from NOAA) plus the maximum uncertainty is greater than the depth of the Mariana Trench. If you want to see just how good our bathymetry maps have gotten, check out the recent work from Scripps Institute of Oceanography.[1] I would usually support qualifying scientific findings, but in this case, there is no place left unmeasured. Therefore there is no "unknown" place that could change this finding. Elriana (talk) 22:29, 20 March 2015 (UTC)

## Mariana Trench Expedition

What was the lowest depth any expedition descended to in the Mariana Trench and what was it's designation and pedigree? — Preceding unsigned comment added by Loki49 (talkcontribs) 19:34, 22 April 2015 (UTC)

1. ^ e.g., Sandwell, David T., et al. "New global marine gravity model from CryoSat-2 and Jason-1 reveals buried tectonic structure." science 346.6205 (2014): 65-67.