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| Holes |
 Title text: If you're thinking 'Wait, a giant crystal cave in Mexico? What's that?' then I'm SO excited for the image search you're about to do. |
Explanation
This comic is a comparison of some of the largest holes in the world, both manmade and natural, showing how high/deep they are, relative to both sea level and the local surface. It is somewhat unusual to refer to many of these as 'holes', which is more normally used to describe small things — most people would hardly call a vast ocean trench a 'hole'.
This comic appears to be related to 1040: Lakes and Oceans.
A table expanding on (but not literally) the various holes is shown below:
| Feature | Type | Approx. elevation relative to sea level | Approx. depth below local surface | Notes | More information |
|---|---|---|---|---|---|
| Bingham Canyon Mine | Open-pit copper mine | ~+1.5 km | 1.2 km | Utah, USA | One of the world's largest human-made excavations, over 1 km deep and several kilometers across. |
| Veryovkina Cave | Cave | ~0 km | 2.2 km | Georgia (Abkhazia) | Currently the deepest known cave on Earth, explored to more than 2.2 km below its entrance. |
| Mponeng Gold Mine | Gold mine | ~−2.5 km | 4 km | South Africa | Among the deepest operating mines ever built, reaching nearly 4 km below the surface. |
| Sanford Laboratory | Underground laboratory | ~+0.1 km | 1.5 km | South Dakota, USA | Former Homestake Gold Mine, now used for experiments in particle physics, neutrinos, and dark matter. |
| Giant Crystal Cave | Cave | ~+1 km | 0.3 km | Naica Mine, Mexico | Famous for enormous gypsum crystals, some over 10 m (33 ft) long, formed in hot mineral-rich groundwater. |
| Derinkuyu Underground City | Underground city | ~+1.3 km | 0.1 km | Turkey | Ancient underground city capable of sheltering tens of thousands of people and their livestock. |
| WIPP | Nuclear waste repository | ~+0.6 km | 0.7 km | New Mexico, USA | The Waste Isolation Pilot Plant stores long-lived radioactive waste in a stable underground salt formation. |
| Restof [Retsof] Salt Mine | Salt mine | ~−0.1 km | 0.3 km | New York, USA | Once the largest salt mine in the United States before major flooding in the 1990s. |
| Jinping Laboratory | Underground laboratory | ~+1.6 km | 2.4 km | Sichuan, China | Built beneath Jinping Mountain and protected by over 2 km of rock, making it one of the world's deepest underground laboratories. |
| San Andreas Fault Observatory Borehole | Geological scientific borehole | ~+0.6 km | 3.2 km | California, USA | Aimed at collecting geological data about the San Andreas Fault for the purpose of predicting and analyzing future earthquakes. |
| CFB North Bay | Military bunker | ~+0.3 km | 0.2 km | Ontario, Canada | Cold War command center carved into solid rock for North American air defense. |
| Woodingdean Water Well | Well | ~−0.3 km | 0.4 km | England, United Kingdom | Hand-dug in the 19th century and still the deepest hand-excavated well ever completed. |
| Diefenbunker | Military bunker | +0.1 km | Near surface | Ontario, Canada | Massive four-story underground bunker built to house the Canadian government after a nuclear attack. |
| Deep Underground Command Center | Proposed military bunker | ~−1 km | Nevada, USA | A proposed U.S. command facility that was never constructed after extensive planning. | |
| Lake Peigneur | Lake | ~−0.2 km | Louisiana, USA | Famous for a 1980 drilling accident that transformed a shallow freshwater lake into a much deeper saltwater lake. | |
| Sydney Opera House Parking | Parking garage | Slightly below sea level | New South Wales, Australia | Deep underground parking beneath one of Australia's most recognizable landmarks. | |
| Onkalo Spent Nuclear Fuel Repository | Nuclear waste repository | ~−0.4 km | Satakunta, Finland | Designed for permanent disposal of spent nuclear fuel for over 100,000 years. | |
| Raven Rock | Military bunker | Near surface | Pennsylvania, USA | Alternate U.S. military command center, sometimes called the "Underground Pentagon." | |
| Delaware Aqueduct | Water tunnel | ~−0.3 km | New York, USA | The world's longest water tunnel, supplying drinking water to New York City. | |
| Wieliczka and Bochnia Salt Mines | Salt mines | ~−0.3 km | Lesser Poland Voivodeship, Poland | Historic medieval mines famous for underground chapels, sculptures, and vast chambers carved from salt. | |
| Atchison Storage Facility | Underground storage | Near surface | Kansas, USA | A former limestone mine converted into climate-controlled storage for records, film, and valuables. | |
| SNOLAB | Underground laboratory | ~−2 km | Ontario, Canada | Located inside an active mine and used for dark matter, neutrino, and astroparticle physics experiments. | |
| Detroit Salt Mine | Salt mine | ~−0.35 km | Michigan, USA | Extensive salt mine directly beneath downtown Detroit and the Detroit River. | |
| Hongyancun Subway Station | Subway station | Near surface | Chongqing, China | One of the deepest metro stations in the world due to the city's steep mountainous terrain. | |
| Nuclear Test Shafts | Test tunnels | ~+1 km | North Korea | Underground tunnels used for nuclear weapons testing beneath Mount Mantap. | |
| Super-Kamiokande | Neutrino detector | ~−1 km | Gifu Prefecture, Japan | Giant underground tank containing 50,000 tonnes of ultra-pure water used to detect neutrinos. | |
| Gran Sasso Laboratory | Underground laboratory | ~+0.7 km | Italy | The world's largest underground research laboratory by volume. | |
| Modane Laboratory | Underground laboratory | ~+1.5 km | France | Built beneath the Alps to shield sensitive physics experiments from cosmic rays. | |
| Gotthard Tunnel | Railway tunnel | ~+0.6 km | Switzerland | The world's longest railway tunnel, stretching 57 km through the Alps. | |
| Cheyenne Mountain Bunker | Military bunker | ~+1.5 km | Colorado, USA | Hardened military complex built inside a granite mountain to survive nuclear attack. | |
| Kola Superdeep Borehole | Scientific borehole | ~-12 km | Murmansk Oblast, Russia | ||
| Lake Baikal | Lake | ~−1.6 km | Russia | The world's deepest and oldest freshwater lake, containing roughly 20% of Earth's unfrozen surface freshwater. | |
| Sediments under Lake Baikal | Sedimentary deposit column | ~-8km | Russia | Lake Baikal sits atop a geological rift, and accumulated sedimentary layers beneath it extend some 7km into the rift. | |
| IDDP-2 Borehole | Geothermal energy borehole | ~ | Iceland | ||
| Dead Sea | Salt lake | ~−0.4 km | Israel/Palestine/Jordan | Earth's lowest exposed land surface, famous for extremely salty water that allows people to float easily. | |
| Ryfylke Tunnel | Road tunnel | ~−0.3 km | Norway | One of the world's deepest subsea road tunnels. | |
| Pantai Remis Mine | Tin mine | Near sea level | Malaysia | A flooded open-pit tin mine that eventually became a lake after its seawall collapsed. | |
| Great Blue Hole | Marine sinkhole | ~−0.1 km | Belize | A giant circular marine sinkhole popular with scuba divers and marine researchers. | |
| JOIDES Resolution Expedition 307 | Scientific ocean borehole | ~−6 km | Atlantic Ocean | Ocean drilling expedition that cored deep into the seafloor to study Earth's geology and climate history. | |
| Deepwater Horizon Borehole | Deep water oil well | ~ | Gulf of Mexico | ||
| Glomar Challenger hole 504B | Scientific ocean borehole | ~ | |||
| Mohole | Scientific ocean borehole | ~ | |||
| JOIDES Resolution Expedition 329 | Scientific ocean borehole | ~ | Atlantic Ocean | Ocean drilling expedition that cored deep into the seafloor to study Earth's geology and climate history. | |
| Mariana Trench | Oceanic trench | ~-10 km | Pacific Ocean | The deepest oceanic trench on Earth. At the bottom, the pressure exerted by the kilometers of water above is about 15000 psi. |
Transcript
- [A large graph is shown, displaying various features of the world on a flat scale. Various holes on it are labelled.]
- [Title of Graph:] Holes
- Elevation is to scale relative to sea level and ground level
- Land shapes and horizontal distances are not to scale
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