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Wed Aug 19, 2020, 12:47 PM

"A Map 15 Years in the Making Illuminates a 'Grand Canyon' off California's Coast"

Don't miss the video animation. Fascinating! https://www.scientificamerican.com/video/a-map-15-years-in-the-making-illuminates-a-grand-canyon-off-californias-coast/

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Reply "A Map 15 Years in the Making Illuminates a 'Grand Canyon' off California's Coast" (Original post)
silverweb Aug 2020 OP
zipplewrath Aug 2020 #1
silverweb Aug 2020 #4
Judi Lynn Aug 2020 #2
silverweb Aug 2020 #3
SCantiGOP Aug 2020 #5
silverweb Aug 2020 #6
SCantiGOP Aug 2020 #7
silverweb Aug 2020 #8
muriel_volestrangler Aug 2020 #9
SCantiGOP Aug 2020 #12
muriel_volestrangler Aug 2020 #13
SCantiGOP Aug 2020 #14
muriel_volestrangler Aug 2020 #15
NNadir Aug 2020 #10
silverweb Aug 2020 #11

Response to silverweb (Original post)

Wed Aug 19, 2020, 12:55 PM

1. Navy probably already knows

Sad to say that the navy probably already knows much of this, but classifies it. Albeit they probably don't care as much about some of those kinds of depths since their subs really can't go anywhere near that deep.

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Response to zipplewrath (Reply #1)

Thu Aug 20, 2020, 01:01 AM

4. Probably.

Unfortunately, I think the Navy is only interested in how they can use it. It's unlikely they care much about it, if at all, in a scientific or environmental sense.

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Response to silverweb (Original post)

Thu Aug 20, 2020, 12:01 AM

2. Wonderful video. Loved the fascinating critters, as well. Looking forward to learning so much more

about this area, hoping they will get really, really busy and examine it thoroughly.

Thank you, silverweb.

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Response to Judi Lynn (Reply #2)

Thu Aug 20, 2020, 12:59 AM

3. My pleasure, Judi Lynn.

I thought of you when I saw this article and had to check to make sure you didn't already post it.

It's wonderfully exciting and amazing to see those animated images. We have so very much to learn about our own incredible planet yet ... if we don't render it uninhabitable first.

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Response to silverweb (Original post)

Fri Aug 21, 2020, 01:13 PM

5. Well worth a few minutes to watch

A trick question is: what is the tallest mountain on Earth measured from its base to its peak?
The volcano that makes up the Big Hawaii island is much taller than Mt Everest, but of course most of it is under the ocean.

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Response to SCantiGOP (Reply #5)

Fri Aug 21, 2020, 01:53 PM

6. I don't think there's an answer yet.

To your trick question, I mean.

Considering that we've explored such a relatively miniscule part of the ocean, there are a lot more wonders to discover -- including the tallest base-to-peak mountain on earth, assuming there's another bigger than the Big Island.

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Response to silverweb (Reply #6)

Fri Aug 21, 2020, 04:45 PM

7. trickery number two

Last edited Sat Aug 22, 2020, 10:52 AM - Edit history (1)

If the criteria is "what is the piece of land that is the furthest from the center of the Earth" the answer again is not Everest. There is a mountain in the Andes that is not listed as "tall" as Everest, but because the Earth's rotation causes a considerable bulge in the Equator (making land along the equator a good deal further from the center than land at the poles), the Andes mountain would be the winner.

You're not going to win any bar bets with this, because if you try to claim that Everest is not the tallest you will either be ignored or punched in the mouth.

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Response to SCantiGOP (Reply #7)

Fri Aug 21, 2020, 09:36 PM

8. LOL

Then it's a good thing I'm not a betting woman or a barfly!



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Response to SCantiGOP (Reply #5)

Sun Aug 23, 2020, 11:55 AM

9. How do you define a mountain's base?

And why is the base of Hawaii not also the base of Everest?

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Response to muriel_volestrangler (Reply #9)

Sun Aug 23, 2020, 01:29 PM

12. Guess there is no clear rule

But the base of Everest is way above sea level, while the base of the Hawaiian mountain is miles under the sea.

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Response to SCantiGOP (Reply #12)

Sun Aug 23, 2020, 02:04 PM

13. So there's no clear rule, but you are able to measure it?

Hmmm.

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Response to muriel_volestrangler (Reply #13)

Sun Aug 23, 2020, 02:18 PM

14. No, geologists who are the accepted experts in these matters

are able to measure it.

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Response to SCantiGOP (Reply #14)

Sun Aug 23, 2020, 03:24 PM

15. Geographers have the measurable concept of prominence

including wet and dry - for both of which Everest beats Maunu Kea:

There are two varieties of topographic prominence: wet prominence and dry prominence.[12] Wet prominence is the standard topographic prominence discussed in this article. Wet prominence assumes that the surface of the earth includes all permanent water, snow, and ice features. Thus, the wet prominence of the highest summit of an ocean island or landmass is always equal to the summit's elevation.

Dry prominence, on the other hand, ignores water, snow, and ice features and assumes that the surface of the earth is defined by the solid bottom of those features. The dry prominence of a summit is equal to its wet prominence unless the summit is the highest point of a landmass or island, or its key col is covered by snow or ice. If its highest surface col is on water, snow, or ice, the dry prominence of that summit is equal to its wet prominence plus the depth of its highest submerged col.

The dry prominence of Mount Everest is, by convention, equal to its wet prominence (8848 m) plus the depth of the deepest hydrologic feature (the Challenger Deep at 10,911 m), or 19,759 m. The dry prominence of Mauna Kea is equal to its wet prominence (4205 m) plus the depth of its highest submerged col (about 5125 m), or about 9330 m, giving it the world's second greatest dry prominence after Mount Everest.[12] The dry prominence of Aconcagua is equal to its wet prominence (6962 m) plus the depth of the highest submerged col of the Bering Strait (about 50 m), or about 7012 m.

Dry prominence is also useful for measuring submerged seamounts. Seamounts have a dry topographic prominence, a topographic isolation, and a negative topographic elevation.

https://en.wikipedia.org/wiki/Topographic_prominence#Wet_prominence_and_dry_prominence

If you draw a small circle around the lowest point on earth, you have also marked off an area on the other side of it, of which Everest is the highest point. For any base you can draw around Mauna Kea, either Everest is in the same defined area, and higher, or there's a second area also defined by that same line - and Everest is the highest point on that side.

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Response to silverweb (Original post)

Sun Aug 23, 2020, 12:22 PM

10. Thank you very much for finding and posting this. It's marvelous.

When my oldest son was small; we took him to this aquarium. It is a wonderful place, and like all good museums, aquariums, arboretums, etc...it takes research seriously.

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Response to NNadir (Reply #10)

Sun Aug 23, 2020, 01:16 PM

11. My great pleasure!

I find all of it absolutely fascinating.

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