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Salt Dome
The US uses hollowed-out salt domes to store the Strategic Petroleum Reserve, and non-hollowed-out ones to store the Strategic Salt Reserve.
Title text: The US uses hollowed-out salt domes to store the Strategic Petroleum Reserve, and non-hollowed-out ones to store the Strategic Salt Reserve.


Ambox notice.png This explanation may be incomplete or incorrect: Created by STRATEGIC SALT SPREADER - Please change this comment when editing this page. Do NOT delete this tag too soon.

This comic refers to how downwards pressure in one area of the world can cause upwards pressure in another, causing geologic structures, like salt domes, to rise up.

In the comic, Beret Guy and Ponytail are sitting at a table and eating dinner alongside Cueball, who is presumably a geologist. When asked to "pass the salt," Cueball, with his extensive knowledge of the Earth's crust and its interactions with the surface, is aware of this pressure phenomenon, and as such is stomping on his chair in order to create downward pressure on the ground beneath. This apparently works exactly as intended, as a salt dome has risen out of the floor and even begun to break through the dinner table. The caption humorously remarks that this is what will happen if you ask any geologist to "pass the salt," which conventionally means to simply hand a salt shaker or dispenser to another diner who cannot reach it. A salt shaker, presumably containing the salt intended to be passed, can be seen on their table. "The general problem" of passing salt and other condiments is discussed in comic 974.

Cueball mentions overburden pressure, a geological term referring to the pressure that outer layers of rock exert on inner layers. This is what usually causes the rising of salt domes; however Cueball's stomping on his chair would not produce sufficient overburden pressure to raise a salt dome.[citation needed] Interestingly, this is exactly the kind of Strange powers Beret Guy, who is also present at the table, usually displays (similar power is shown in 1388: Subduction License).

The title text mentions the Strategic Petroleum Reserve, a United States government reserve of oil for use in emergencies. Randall observes the true fact that artificial caves within hollowed-out salt domes create the spaces for storage of this oil; in fact, naturally-occurring petroleum is often found under salt domes. The joke in the title text is Randall's claim that salt domes that are not yet hollow are used to store the US salt reserve. Of course this could be seen as true, but this salt is not put there by humans, but by nature, and is thus not stored there by any government. Further, the use of the term "salt dome" in the title text plays on the ambiguity between geological salt domes and the monolithic dome structures commonly used to store reserves of road salt, which also are commonly referred to as "salt domes".

Ordinary salt is available in abundance throughout the U.S.[1] so there is no need for a national strategic salt reserve.[citation needed] However, the UK does maintain an Emergency Salt Reserve[2] as part of a Strategic Salt Protocol[3] to ensure highways can be salted during prolonged wintry weather, just as most communities throughout the world regularly using salt on roads stockpile it for such purposes.


[This comic is drawn on a gray background, with the segment beneath the floor in dark gray. This is to make the white part of the comic stand out as very white. In the comic Cueball, Beret Guy and Ponytail are dining at a long table, with Cueball and Ponytail far from each other at the either end of the table. Beret Guy sits close to Cueball, facing towards the reader, and he is quite far away from Ponytail. Beret Guy and Ponytail are sitting down in their chairs, Ponytail with her hands in her lap, Beret Guy with his arms on the table. Their chairs are quite high, neither of them are even close to reaching the floor with their feet. Cueball, on the other hand, is standing on his chair and is loudly stomping on the chair. This has caused the floor beneath the chairs legs to be dented slightly down. And a white column of salt has burst through the ground and is rising up under the table clearly bending the table up in the process, and the table surface is cracking up in several places. The white dome, the only white part of the image, is broader at the top than where it breaks through the floor, but widens out beneath the floor. The white salt has several small black spots on it, to indicate a rough surface. On the table there are three dining plates with food, a bowl and a plate with food, about to slide down the domed table surface, and two wine glasses, one of which has fallen over due to the deformation of the table. It has fallen over near Ponytail releasing the liquid out on the table, where it runs out over the side. Between Cueball and Beret Guy there stands a salt shaker, that could have been passed to Ponytail.]
Cueball: Just a little more overburden pressure...
Cueball: The dome is almost through the table...
Cueball stomping: Stomp stomp
[Caption below the panel:]
Never ask a geologist to pass the salt.

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