What's the Deepest Hole Ever Dug? | Hacker News Reader

What's the Deepest Hole Ever Dug?

smithsonianmag.com

59 pointsmpweiher52 comments

Just a bit of pedantry - the story linked (correctly) identifies the Kola superdeep borehole near Pechenga, Russia as the deepest hole humanity has ever drilled, at some 12,200m/40,000ft.

However, 'dug' in my book is not the same as drilling; the deepest hole ever dug (unless you want to go all fundamentalist and claim 'dug' implies shovels and pickaxes and nothing else!) is the Bingham Canyon open-pit mine in Utah, at some 1,200m/4,000ft. (They've been at it for more than 100 years!)

The deepest mine? Mponeng and TauTona, two South African gold mines, at approx. 4,000m/13,000ft. (And counting!)

Deepest hand dug well is in Brighton - 1285ft: https://www.woodingdeaninbusiness.co.uk/blog/where-is-the-wo...

Thanks for this, reading the article made me curious about this too.

The folks at Cards Against Humanity () didn't get too close to the record. They also ran out of funding like most of the projects mentioned in the article...

https://www.theguardian.com/technology/2016/nov/28/cards-aga...

> The Kola hole was abandoned in 1992 when drillers encountered higher-than-expected temperatures—356 degrees Fahrenheit, not the 212 degrees that had been mapped.

That, plus the collapse of the Soviet Union.

Then: https://www.thevintagenews.com/wp-content/uploads/2015/11/01...

Now: https://f4.bcbits.com/img/a4184178639_16.jpg

I wonder why not investment goes into tapping the geotermal potential. Is like having a free reactor ( since both work on transferring heat to water -> steam )

Most geothermal installations are near tectonic plate boundaries and require drilling only a few hundred metres or less. Being able to go down further would open up the possibility of using geothermal power in other regions, but it's very expensive.

Educated guess: it's very hard.

A pipe that long would be subject to break down every time the earth moves a bit. Fixing said leak would requires stopping the use of the pipe completely.

As 300 C is not that a huge temperature, the energy to pump the water may also cost a lot compare to the energy you get out of it.

I'm not saying we should not try, but it seems a great challenge. And we don't have the motivation of creating an atomic bomb to drive it.

With only a very tenous grasp on the basics of fluid mechanics and thermodynamics, I'd suspect it is simply a lot more cost effective to drive a significantly larger volume of water through a significantly shallower (hence, lower temperature - but cheaper to drill, maintain and force water through) well to reap the same amount of energy.

Assuming reasonable heat exchange efficiencies, you'd do as well with 1000m^3/hour at a 20 degree differential as you would with 100m^3/hour at a 200 degree differential.

Or am I missing something?

Yes, but if you can turn the water into steam you don't have to pump it back as much. So you leverage gravity in, density out. I have no idea if that evens out though.

City of Espoo is testing, 6+ km hole for energy, google for "Otaniemi drill hole" for more information.

Previous (recent) HN topic on the same thing: https://news.ycombinator.com/item?id=17336315

Real Life Lore Video: https://www.youtube.com/watch?v=E39GIysMevQ

Is the transition from crust to mantle a sudden one or gradual? It seems unlikely that the two could be entirely separate. And how about between the mantle, outer and inner cores?

Strange drilling fact: When digging the Channel Tunnel, all existing bore holes (going back a century) had to be mapped and the tunnel avoided them so that if any of them hadn't been plugged properly it wouldn't create a hole that caused the tunnel to fill with water.

It's complicated. https://en.wikipedia.org/wiki/Transition_zone_(Earth)

An interesting article but infuriating in how it translates all dimensions to Imperial first. Such as stating the depth of the Kola borehole in feet and adding metres in parentheses; it was drilled using equipment specified in metres...

The Smithsonian is an American institution and as such caters to American's habit of using Imperial measurements. This makes it more relatable to the the passing reader.

I kinda like the idea that Americans could be gradually migrated from Imperial to metric by osmosis over the course of a few thousand measurement based scientific articles.

Science, even at the level of secondary school classes, has used metric in the US for a very long time. I don't know where people get this weird idea that Americans don't use SI. Imagine Americans making fun of Europeans for not speaking English, because they thought multilingual = not speaking English. That's how silly this meme is. Every car I've ever owned had km on the speedometer.

> Every car I've ever owned had km on the speedometer.

Same here. (Although, I've driven a couple cars that only had a single scale of digits on the gauge. Pressing a button would toggle the meaning of the numbers from mph to km/h and swing the needle around to point at whatever was correct.)

They may take our lives, but they'll never take our feet!

Problem is that the issue is not just about the numbers and units people expect to use.

The other issue relates to the fact that we build things according to imperial dimensions. (Paper is 8.5x11, bolts have sizes in imperial units, screw threads are pitched according to inches, etc.)

Some or all of this can be changed, but neither the change nor the transition are free. (ie: I two sets of tools - one for metric and another for imperial.)

It’s hard enough to get readers for measurement based scientific articles, I imagine.

You're easily infuriated.

Literally the whole world uses SI, only USA plus a few small countries chose to remain in the dark ages.

This is of course not true. If I go to England I’ll see & hear references to ‘stone’ for weight.

Similarly most of the world uses Celsius instead of Kelvin for temperature.

In China you’ll see measures denominated in duplicate units at times.

The world over you’ll see variations in what units people use.

And in India, we still use a more traditional counting system beyond thousands - we say "lakh" for 100,000 and "crore" for 10,000,000. The words million and billion are not in common use.

The UK also uses mpg, and confusingly enough, the Imperial gallon is significantly larger than the American one.

So a system of measurement determines whether people are in the "dark ages." I see.

When you set human extremities as references instead of fundamental physical properties, yes.

You're misinformed. A foot as a measurement in 2018 has no more to do with a human foot than a computer chip has to do with a potato-powered calculator. Imperial units have had standard metric translations for a long time.

Of course, you can use or invent whatever measure system you like, if you provide a translation. But why translate? Why not use what the rest of the world uses?

When you come from the outside, it feels like a trip to middle ages reading about 'furlongs', 'hogsheads' and 'pennyweights'.

https://en.wikipedia.org/wiki/United_States_customary_units

> it feels like a trip to middle ages reading about 'furlongs', 'hogsheads' and 'pennyweights'.

I've lived in the United States for my entire life (43 years) and have never come close to ever seeing these units in use. To be honest, while I've heard of them, I couldn't even give a reasonable definition. I'm pretty sure the primary modern use for these units is either as a historical curiosity or as a way to pass judgement.

"There's this widespread legacy system. Why won't those stupid people just migrate to the newish and better one?" (Key words: legacy, migrate. I still see dozens of WinXP systems around, alive and kicking.)

That's exactly it. Metric is on every single food item. Food is like a modern 64 bit system. Meanwhile, the roads are still in miles per hour and all temperatures are in Fahrenheit, so I need an 8 bit subsystem to run it.

I would have to convert back to feet and miles if the article didn't have it because I'm not used to those units since I never have an opportunity to use them in my daily life. Metric is not as intuitive as its promoters insist. Intuition is developed through use.

Civilization-scale issues require civilization-scale solutions. I can't unilaterally convert to metric in every context because it would be terribly impractical. I would spend my days doing conversions. That's a huge waste of finite time and energy.

> Food is like a modern 64 bit system. Meanwhile, the roads are still in miles per hour and all temperatures are in Fahrenheit, so I need an 8 bit subsystem to run it.

The problem with that analogy is that a 64-bit computer is inherently, in isolation, much more powerful than an 8-bit. For the vast majority of cases, the same is not true for a switch from from, say, ounces to ml to measure the size of a bottle of water.

That's a bit of a mixed bag. Once you do realize that 1 cm3 (1 ml) of water is also 1 g (as it's 1000g/1l = 1g/1ml), and that a 10x10x10 cm cube is 1 l (and is 1 kg), it does get powerful in unexpected ways ("cook half liter of water...hm, how do I measure...well that's 500 ml, so I'll just weigh 500 g, exactly the same thing"); and a 10 l bucket of water weighs 10 kg; similarly with other decimal units. This, I think, is intrinsically useful - how does this translate into US units, are there such simple conversions? (IDK, so this is not a rhetorical question)

> how does this translate into US units, are there such simple conversions?

Not really. I have a couple of these types of conversions committed to memory (1 gal water = 7 pounds, etc.), but it's all pretty ad hoc. That said, I haven't found too much use for it.

All that said, I very much appreciate the orthogonality and consistency of SI. In an ideal world, the US would be on it, or at least on something the same as the rest of the world. Aside from sheer habit, I think the most compelling argument for the reason we aren't is that the units we use are so heavily baked into physical objects.

The US put a god damned man on the moon, they're far from dark ages.

And lost a mars orbiter thanks to the US customary units.

https://en.wikipedia.org/wiki/Mars_Climate_Orbiter#Cause_of_...

Think what could have happened if the Apollo Program was an international effort and not a U.S. only one.

Probably wouldn’t have left low Earth orbit [0].

For better or worse more effective organizations generally present themselves as a unit with aligned interests. Organizations with misaligned internal interests get as far as the lowest common denominator among their interests weighted by the relative power of members. That’s a far more significant factor than choice of measurement standards.

0. https://en.wikipedia.org/wiki/International_Space_Station

The US uses SI and has for a long time. This is ridiculous propaganda. Source: Personal experience - I took high school science classes in the US, in the first half of the 90s. I've also owned metric tools purchased in the US, and several cars with metric measurements on the gauges.

I routinely buy my liquor in ml, though I refer to them by non-imperial measure (“a handle”).

As far as I know everything you'd find in a US grocery has the measurements printed in metric and avoirdupois, but sometimes the metric measurement is a round number, and sometimes the other one.

If you look at the Wikipedia page about the 2L soda bottle, it states that round metric numbers are rare in the US, but I don't know that this is accurate* - if I look at alcohol on Wal-Mart's web site, it generally seems to be in quantities of 750ml, 1.75L. That's hard liquor, but for example rice cooking wine is also sold in 750ml. Regular wine is standardized on 750ml (occasionally 1.5L) bottles as far as I know.

Then there are things that don't make sense in any units - there is a bottle of cooking wine that is 12.9 fl oz and 381 ml.

*And it had no citation.

The metric system is widely used in the U.S. school system? That is news to me.

Since at least 1975 when a federal law was passed making metric the “preferred” measurement system.

In the 80s I was doing metric conversions in years 4 or 5.

I grew up in the U.S. We were taught to use the metric system throughout my schooling and used it (metric) for all science courses in university.

But in my university engineering labs on machining and machine tools, it was all taught in inches and feet. Not sure if that's because that's what industry used. I never entered my career as a manufacturing engineer.

For some odd reason, a lot of mechanical engineering and machining in the US is still done in inches and feet, though I think most of it is related to the defense sector. If you get into the automotive sector, for instance, you won't see that any more; they finally went all-metric in the 90s or so. Anything where the product is going to be sold internationally is probably metric.

In other engineering disciplines (except maybe civil), it's all metric. You won't hear EEs talking about semiconductor feature sizes in fractions of an inch.

Even back to the early 90's, it was the one and only unit system used in science classes.

There are countries that use the metric system and countries that have been to the moon. :-)

Well... https://en.wikipedia.org/wiki/Lunokhod_programme

The Third Reich? Ah no, it was just their rocket scientists wasn't it.

Von Braun never was an astronaut, much less traveled to the moon. And, I presume Nazi Germany used metric.

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