# Have we been deeper than the Marianas Trench? **URL:** \ **Category:** Factual Questions\ **Created:** [June 25, 2009, 5:59pm UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967 "2009-06-25T17:59:06Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![Sapo](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Sapo](https://boards.straightdope.com/u/Sapo)\ **Post date:** [June 25, 2009, 5:59pm UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/1 "2009-06-25T17:59:06Z")
Go crazy with the jokes. Now, starting from the surface of the Earth (and correcting for altitude above sea level where needed), have we dug deeper on the ground that we have gone under the surface of the sea? Please make the distinction between manned (mines, tunnels, etc) and unmanned (oil wells, nuclear blasts, etc). ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [June 25, 2009, 6:10pm UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/2 "2009-06-25T18:10:23Z")
People haven’t, but they have drilled deeper. The deepest hole ever drilled in the crust, on the Kola Peninsula in Russia, was 12,261m (40,230ft), compared with 10,924m (35,840ft) for the Mariana Trench. See [Kola Superdeep Borehole - Wikipedia](http://en.wikipedia.org/wiki/Kola_Superdeep_Borehole) I’m not sure what the altitude above sea level of the top of the hole is, but I’m fairly certain it’s not more than 1,000 metres, so the bottom of that hole is further below sea level than the Mariana trench (and much nearer the centre of the Earth, given that it is closer to the pole). ETA: As far as I can tell, the deepest that humans have been is at the TauTona mine in South Africa, at about 3,900m (13,000ft). [TauTona Mine - Wikipedia](http://en.wikipedia.org/wiki/TauTona) ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [June 25, 2009, 6:13pm UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/3 "2009-06-25T18:13:48Z")
In 1962 the Russians began planning a drill hole deep enough to reach and sample the Moho (Mohorovicic Discontinuity). The site they chose was the Kola Penninsula and actual drilling began in 1970. 24 years later, the deepest of several offsets (arms) extended to a greatest depth of 7.1 miles, or 12,262 meters. The Mariana Trench is 11,033 metres from ocean surface to max depth. ETA: I see **Colophon** and I provide slightly different depths but the same conclusion. ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [June 25, 2009, 6:21pm UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/4 "2009-06-25T18:21:55Z")
Timed out… 11,033 meters was claimed by Russians but not reverified. 10,924 should probably be used. ---
**Author:** ![SmashTheState](https://avatars.discourse-cdn.com/v4/letter/s/e36b37/32.png) [@SmashTheState](https://boards.straightdope.com/u/SmashTheState)\ **Post date:** [June 25, 2009, 7:57pm UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/5 "2009-06-25T19:57:44Z")
How deep is [Hell](http://en.wikipedia.org/wiki/Well_to_Hell_hoax)? ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [June 25, 2009, 8:22pm UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/6 "2009-06-25T20:22:10Z")
> [@Colophon](#): > > ETA: As far as I can tell, the deepest that humans have been is at the TauTona mine in South Africa, at about 3,900m (13,000ft). [TauTona Mine - Wikipedia](http://en.wikipedia.org/wiki/TauTona) The deepest in a subsurface drilling or excavation, that is. Bathyscaphic expeditions to the abyssal floor have of course been lower on a depth-below-sea-level basis, the record of course being the catch-phrase twenty minutes in 1960. ---
**Author:** ![Sapo](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Sapo](https://boards.straightdope.com/u/Sapo)\ **Post date:** [June 26, 2009, 1:19am UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/7 "2009-06-26T01:19:49Z")
Cool stuff both on Kola and TauTona. Now why did Kola stop by finding temperatures of only 180oC? Aren’t all those parts made of super hard metals with their respective super high melting points? I don’t see how 180oC should be an obstacle. Or even the predicted 300 at the target depth. ---
**Author:** ![Jihi](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jihi/32/17768_2.png) [@Jihi](https://boards.straightdope.com/u/Jihi)\ **Post date:** [June 26, 2009, 2:05am UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/8 "2009-06-26T02:05:32Z")
> [@Sapo](#): > > Go crazy with the jokes. Once. But only for 20 minutes. (I know, I know, but someone had to do it… I’ll gladly take the bullet.) 😛 ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [June 26, 2009, 2:27am UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/9 "2009-06-26T02:27:42Z")
> [@Polycarp](#): > > being the catch-phrase twenty minutes in 1960. I really wish you guys would quit talking about my sex life. Offhand, I’d say the Russian deep drilling didnt stop due to temp. There are other reasons why drilling that deep becomes a problem. ---
**Author:** ![WoodenTaco](https://avatars.discourse-cdn.com/v4/letter/w/45deac/32.png) [@WoodenTaco](https://boards.straightdope.com/u/WoodenTaco)\ **Post date:** [June 26, 2009, 2:38am UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/10 "2009-06-26T02:38:47Z")
There are also some significant political events that might have made things complicated around 1992 in Russia. No evidence to back that up really, but it seems reasonable. ---
**Author:** ![Rufus\_Xavier](https://avatars.discourse-cdn.com/v4/letter/r/eada6e/32.png) [@Rufus\_Xavier](https://boards.straightdope.com/u/Rufus_Xavier)\ **Post date:** [June 26, 2009, 3:36am UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/11 "2009-06-26T03:36:37Z")
> [@billfish678](#): > > I really wish you guys would quit talking about my sex life. > > Offhand, I’d say the Russian deep drilling didnt stop due to temp. There are other reasons why drilling that deep becomes a problem. See, now you’re talking about _my_ sex life. ---
**Author:** ![Alex\_Dubinsky](https://avatars.discourse-cdn.com/v4/letter/a/dbc845/32.png) [@Alex\_Dubinsky](https://boards.straightdope.com/u/Alex_Dubinsky)\ **Post date:** [June 26, 2009, 3:59am UTC](https://boards.straightdope.com/t/have-we-been-deeper-than-the-marianas-trench/500967/12 "2009-06-26T03:59:53Z")
> [@Sapo](#): > > Cool stuff both on Kola and TauTona. Now why did Kola stop by finding temperatures of only 180oC? Aren’t all those parts made of super hard metals with their respective super high melting points? I don’t see how 180oC should be an obstacle. Or even the predicted 300 at the target depth. Maybe they were pissed off they hadn’t hit 300. After all that drilling…