3078: Anchor Bolts

2025-04-19T05:05:12Z

162.158.41.45:

{{comic
| number = 3078
| date = April 18, 2025
| title = Anchor Screws
| image = anchor_screws_2x.png
| imagesize = 381x326px
| noexpand = true
| titletext = The biggest expense was installing the mantle ducts to keep the carbonate-silicate cycle operating.
}}

==Explanation==
{{incomplete|Created by an AUTOMATIC SUBLIMATOR. Don't remove this notice too soon.}}

The comic displays a subduction zone. Tectonic plates are plates that divide the Earth's crust. They slowly move across the Earth's surface at the rate of a few centimeters per year, although the rate is nonuniform across plates. When they collide, the denser plate gets dragged under the less dense plate, in a process called subduction. Earthquakes are common at subduction zones, and subduction can also trigger volcanic activity. Earthquakes and volcanic eruptions are typically bad for humanity, {{citation needed}} and thus ways to prevent them happening would reduce economic risks in those areas. An "anti-subduction anchor screw" would effectively stop the process of subduction and the movement of plate tectonics as a whole.

A round head screw is screwed in through both the oceanic lithosphere and the continental crust from the bottom up, with a plain washer on either side, and a wing nut tightened at the surface. Washers are present to prevent the screw and the wing nut from sinking into the crust. There are several concerns not addressed in the comic with such a design. The implication that the screw is being screwed in from the mantle side would imply that a very large screw head was operated from inside the mantle. As of the time of posting of the comic, humans have not drilled a hole through a continental crust, still less deployed large vehicles in the mantle. In addition, the presence of wing nuts, fasteners that are designed to be able to be screwed in by hand, implies work done by a larger being that has appendages able to use the wing nut. The screw itself would be a technological challenge, as well. The temperature of Earth's mantle is around 1000°C near the surface, temperatures at which most commercial stainless steel used to manufacture screws would experience noticeable strength losses. As such, materials capable of withstanding higher temperatures would need to be utilized. The screw itself would need to have a length of around 50 km as well. Moreover, as subduction zones move parallel to each other, the construction would have to withstand high shear forces, something that the screw is rather unsuited to compared to other tools such as rivets. On top of that, ways to alleviate stress must be sought out as if the screw fails, it could produce a highly amplified earthquake.

The title text references the {{w|Carbonate–silicate_cycle|Carbonate-silicate geochemical cycle}}. Briefly, subduction and subsequent heating of the global crust restores carbon dioxide and silicate rocks to the planetary surface, countering the effects of carbonate deposition and silicate rock weathering. Anchor screws sufficient to stop plate tectonics would also stop the carbonate-silicate cycle, leading to unexpected, and likely unwelcome, changes in the surface geosphere and biosphere. To restore the cycle by an unknown mechanism, "mantle ducts" have been installed as part of the planet-wide plate anchoring system. It is stated that the mantle duct installation was the "most expensive" part of the project, implying greater intellectual and technical challenges than the already-massive ones associated with anchor-screw design and deployment.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}

{{comic discussion}}

[[Category:Subduction]]
[[Category:Geology]]

Talk:3078: Anchor Bolts

2025-04-19T04:09:38Z

162.158.41.45:

As a kid, I was ALWAYS worried about how plate tectonics would change the continent's layout in a few hundred million years' time, along with how the Sun will die (and maybe consume the Earth if we don't move it) in five billion years. Young me would be SO glad we are finally fixing the first issue. [[User:MinersHavenM43|MinersHavenM43]] ([[User talk:MinersHavenM43|talk]]) 03:28, 19 April 2025 (UTC)
: Was young you a Superman fan, and did you ever wonder what <em>really</em> happened on Krypton? Scientists and engineers, funded and enabled by a Trump-style politician and his promise to "Stop The Earthquakes <em>NOW!</em>", actually overcame (temporarily) the materials issues and solved the stress equations (see below), and installed a (temporarily) successful planetary plate-anchoring system. Jor-El objected to the project, he and any who supported him were de-funded as a result, and he spent his remaining time ensuring that he could get his son the [deleted] outa there before the accumulated strain ruptured the anchors and blew the planet apart. [[Special:Contributions/162.158.41.45|162.158.41.45]] 04:09, 19 April 2025 (UTC)

Would an anti-subduction screw really work? The tectonic plates are slow, but they are quite heavy, so they have a fair bit of momentum. Indeed, enough to overcome the not inconsiderable friction already present due to the weight of the uplifted portion of the upper plate. Such a screw would therefore need to exert quite a bit of additional pressure to bring the motion to a halt; Exactly how much I shall leave as an exercise for the reader (because I have no clue where to even start trying to work it out), but my guess is that you're gonna need some seriously high tensile strength material for these, even if they are placed at very short intervals along the plate boundary. [[Special:Contributions/172.68.84.172|172.68.84.172]] 03:52, 19 April 2025 (UTC)

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3078: Anchor Bolts

Talk:3078: Anchor Bolts