Editor’s note: The Trivia Geek is once again away supervising a project of deep technical significance — the redesign of TechRepublic newsletters. In the meantime, he has reached way back into the archives to grab this Classic Geek, which originally ran on Aug. 13, 2003.

What do you get when you combine a nuclear explosive, several hundred thousand tons of molten iron, a stockpile of grapefruit-size spherical high-temperature probes, and access to the Laser Interferometer Gravitational Wave Observatory (LIGO)?

Why, the world’s most ambitious geophysical experiment, of course. You simply use the nuclear explosive to blast open a hole in the Earth’s crust, pour in a cocktail of molten iron and probe spheres, and use LIGO to monitor the vibratory feedback of the injected metals as they sink quickly to the Earth’s core — 3,000 kilometers below.

Caltech scientist David J. Stevenson suggested this super-scale measure to probe the Earth’s core. But don’t think this makes Stevenson a maverick; scientists have been aching to poke massive holes in the Earth’s crust for decades.

The probe concept is an offshoot of a Russian scheme called Hot Drop. This project envisioned bundling nuclear waste in large tungsten balls, superheating the spheres to 1,200 degrees Celsius, and then allowing the tungsten constructs to melt through the Earth’s crust and into the mantle, where the radioactive material could decay safely.

Needless to say, the Hot Drop concept met resistance from several environmental and political groups, all of whom contend that importing, stockpiling, boiling, and dumping nuclear waste might be a risky proposition.

Still, to give the Russians credit, they are the undisputed kings of deep hole drilling. In fact, the deepest hole ever dug is the result of a Russian effort to probe extreme-depth geology.

WHAT IS THE DEEPEST HOLE EVER DUG BY HUMANKIND?

Get the answer.

What Russian scientific achievement, considered a geological landmark, produced the deepest hole ever dug by humankind?

The Kola Superdeep Borehole, located in Russia’s Kola Peninsula, reached a final depth of more than 12 kilometers.

The project began in the early 1970s as a strictly scientific measure. Over the next three decades, Russian teams employed exotic drilling techniques in an effort to breach the 12-kilometer barrier. The Borehole’s depth is as much a testament to perseverance as it is to technical prowess.

A similar U.S. endeavor, dubbed Project Mohole, reached less than a kilometer in depth before political and technical obstacles prompted Congress to cut funding in 1966, only five years after the project began. Project Mohole sought to penetrate the Earth’s crust at its thinnest — below the ocean’s surface.

The only western excavation that came close to the Borehole’s depth — and was briefly the record holder for the world’s deepest manmade hole — is the Bertha Rogers oil well in Oklahoma. The well reached a final depth of more than 9.5 kilometers before it impacted a molten sulfur deposit in 1974. Naturally, the Bertha Rogers oil well was part of a commercial venture and provided relatively few scientific discoveries.

The Kola Superdeep Borehole eventually overtook the Rogers well and has outpaced all competing efforts to remain one of the “deepest” scientific achievements in history.

The Quibble of the Week

If you uncover a questionable fact or debatable aspect of this week’s Geek Trivia, just post it in the discussion area. Every week, yours truly will choose the best post from the assembled masses and discuss it in a future edition of Geek Trivia.

This week’s quibble comes from the July 31 edition of Geek Trivia, “Glimpsing the sub(marine)text.” TechRepublic member bryant busted me for my description of the final resting place of the USS Nautilus.

“You state ‘though it’s now serving as a museum piece outside the U.S. Navy shipyards in Groton, CT.’ The Nautilus museum is outside the Naval Sub Base in Groton; it is technically not a shipyard as they do not build or repair subs there. The shipyard (Electric Boat) is several miles upriver and is a private shipyard, not a U.S. Navy shipyard.”

Well, I’ll concede to almost every point you make. As member gp pointed out, “Electric Boat, located in Groton, CT, is approximately three miles downriver from the U.S. Navy submarine base located in New London, CT.”

Thanks for the nomenclature and geography lessons, and keep those quibbles coming.

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The Trivia Geek, also known as Jay Garmon, is a former advertising copywriter and Web developer who’s duped TechRepublic into underwriting his affinity for movies, sci-fi, comic books, technology, and all things geekish or subcultural.

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