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| Subduction Retrieval |
 Title text: Aww, the oceanic crust and the continental crust are getting married! |
Explanation
This comic is a public service announcement (PSA) telling the reader to stay out of the Pacific Ocean on the current day. The reason for this is explained to be that someone has lost their wedding ring in a subduction zone. This is a boundary where two tectonic plates in the Earth's crust collide, and one plate dives beneath the other into the Earth's mantle. The ring can be seen glimmering on the upper surface of the subducted oceanic plate, in the accretionary wedge below the continental plate. Given that the rate at which this occurs is of a few centimetres per year at most, and assuming that the characters shown are drawn to scale and are of average human stature, it can be estimated that the ring has been in the subduction zone for about 200 years. Possibly this time has been needed to localise it and then deploy the heavy engineering displayed.
As a result, the United States Geological Survey (USGS) is "pulling the plate back up" to retrieve the ring. This would be a ridiculous idea, since no man-made machine is capable of moving entire tectonic plates.[citation needed] Even if it were possible, it is unlikely that the USGS, a national organization, would invest the time and effort required for such an operation for the relatively trivial purpose of retrieving a wedding ring, particularly for people who are presumably long since dead. If they did, though, staying out of the ocean would be a good idea, as it would be liable to cause tsunami over a wide area, as well as other dangers.
The title text jokes that since the wedding ring lies on the lower (oceanic) plate, the oceanic crust and continental crust are "getting married". Of course, most humans wouldn't be able to see the sight of the wedding ring, due to it being underground, and in the mantle, where no human could reach anyway โ assuming that it hadn't already been mechanically deformed (crushed, mangled and/or broken apart) by the action of being sandwiched between two continental masses, and eventually melted.
Transcript
[A large structure resembling a bridge has been positioned over the intersection of two tectonic plates, one under the ocean and one forming a jagged, mountainous coast, with one "foot" on each plate. A winch is hanging from the center of the bridge, connected to a chain which is hooked into the oceanic crust. The winch is pulling up the crust, causing it to fold and wrinkle. Cueball and Ponytail are standing on one large fold next to where the chain is hooked to the crust, and another Cueball is standing on the continental crust. Oceanic Cueball has his arms up. On a portion of subducted oceanic crust, far below the ground, a small shining lump is visible.]
[Winch:] click click click
[Caption below panel:] PSA: Please stay out of the Pacific Ocean today. Someone lost their wedding ring in a subduction zone and USGS is pulling the plate back up to retrieve it.
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