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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 Tsunami or Tidal Wave - 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 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. Thus, when asked to "pass the salt," Cueball, with his extensive knowledge of the Earth's crust and its interactions with the surface world, is aware of this 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 begins rising out of the floor and even begins 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.

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, though Cueball's stomping on his chair would not produce sufficient overburden pressure to raise a salt dome.[citation needed]

In the title text, the Strategic Petroleum Reserve is a United States government reserve of oil in case of emergencies. Randall observes the actually true fact that artificial caves within hollowed-out salt domes create the spaces for the government to store this oil. Ordinary salt is available in abundance throughout the U.S.[1] so there is no need for any kind of salt reserves, strategic or otherwise.[citation needed]


Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[Cueball, Beret Guy and Ponytail are sitting at a table. Beret Guy and Ponytail sit patiently; Cueball is stomping on his chair, and the ground has been dented very slightly by the legs of his chair. A white column of salt has burst through the ground and is rising up, slightly cracking and bending the table in the process. There are plates of food, drinking glasses, and a salt shaker on the table. One of the glasses has fallen, releasing what seems to be wine.]
Cueball: Just a little more overburden pressure...
Cueball: The dome is almost through the table...
[Caption below the panel:]
Never ask a geologist to pass the salt.

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