explain xkcd:Museum

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Landscape Features

|< < Prev #3221 (March 18, 2026)

Title text: 'Well, there's speculation that it's due to a mantle hotspot.' --a geologist who's trying to cover up the fact that they didn't hear your question

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Explanation

This is incomplete: This page was created by a MANTLE HOTSPOT. Don't remove this notice too soon. If you can fix this issue, edit the page!

This comic is a map of the United States, purporting to explain some of the most significant geologic/human activity in each region. For each area it names one major mechanism (plate tectonics, erosion, volcanism, etc.) which it claims is responsible for the majority of interesting formations and features.

Many of these causes are summarized in a single word answer, which doesn't do much to explain a complex landscape. A few phrases are longer but still don't actually explain much. And some areas are just labeled "geology".

The title text plays off the fact that a large part of geology is concerned with activity in the mantle, so explaining some geologic feature by saying "there's speculation that it's due to a mantle hotspot" does not give much information. Saying this would let a distracted geologist buy time while responding to a missed question. Many of Earth's seemingly out-of-place features (e.g., Hawaii hotspot, Iceland, the Snake River Plain in Idaho, etc.) form from such mantle hotspots. Thus, it's an easy go-to explanation for many of the geological features people are often most curious about.

Location	Description	Explanation
Adirondack Mountains	???	The Adirondack Mountains are made of billion-year-old rock but were uplifted relatively recently, within the last 5–10 million years. They’re still rising today despite being far from any plate boundary, forming a dome with no clear tectonic cause, thus the "???" due to an ongoing mystery as to their formation.
Most of northern conterminous U.S.	glaciers	During the Last Glacial Period, this area was covered by an ice sheet that left its marks on the landscape, in the form of moraines, eskers, glacial erratics, etc.
Appalachian Mountains	continents colliding	Geology of the Appalachians
Near Mississippi & Ohio Rivers	rivers	Ohio River Geology
Southeastern U.S.	farming	Landscape changes from cotton production in the United States, due to the presence of the Black Belt (geological formation).
Southern Florida	ongoing disputes between limestone and water	Karst topography
Southern Missouri/Northern Arkansas	geology	The Ozark Mountains, which are composed primarily of ancient limestone and dolomite, form a rugged landscape characterized by hills, caves, and springs. Prolonged erosion of these soluble rocks has produced extensive karst features, including sinkholes and underground rivers.
Great Plains	farming	The lack of other major events left the terrain relatively level, and areas were historically shaped by either herds of bison or indigenous agriculture, both limiting the growth of forests. "Farming" is likely a reference to the more recent mix of large-scale crop farming (especially staples like wheat and corn) and herding (bison replace by cattle).
Central Idaho/Yellowstone	a supervolcano	The Snake River Plain is an area of high-elevation flat plain in the otherwise contiguous Rocky Mountains. It was formed by the movement of the continental plate over the Yellowstone Hotspot.
American West surrounding Idaho/Yellowstone	geology	3162
Immediately off of West coast up to the Four Corners	volcanoes	A combination of various volcanic fields of different origins, including Cascade Volcanoes in the Pacific Northwest, Albuquerque volcanic field in New Mexico, San Francisco volcanic field in Arizona, and San Juan volcanic field in Colorado.
Eastern Washington	megafloods	Most likely a reference to the Missoula floods and the Bonneville flood, a series of floods caused by glacial ice dam failures causing massive lakes to flood large regions of present-day eastern Washington. These floods actually continued all the way to the Pacific Ocean, altering the shape of the Columbia River Gorge and flooding much of the Willamette River in western Oregon. The comic may have simplified these to avoid bisecting the adjacent zones along the coast.
West Coast	a plate tectonic speedrun	Most likely a reference to the significant tectonic activity on the western coast of the US, caused by the collisions of the Juan de Fuca plate, Pacific plate, and the North American plate, as part of the Ring of Fire.
Desert Southwest	water and time
Northern Alaska	geology
Aleutian Islands	volcanoes	The Aleutian Islands are a continuation of the Alaskan Aleutian Range, and form part of the Ring of Fire. Most of the islands in the chain bear signs of being formed by volcanoes, and many volcanic cones still exist on the islands today.
Southeast Alaska	glaciers	This part of Alaska (including Glacier National Park) and western Canada has many glaciers that are still carving the landscape.
Hawaiian island chain	volcanoes	Hawaii, including the Northwest Hawaiian Islands, and seamounts northwest of it were formed by a tectonic plate moving over a hotspot, with volcanoes erupting and forming land as it went. The entire chain can be seen here.

Feature of Each State

Washington: Mega floods, a plates tectonics speedrun

Idaho: a super volcano, geology

Montana: geology, glaciers

North Dakota: glaciers, farming

This map with subdivisions follows up on a number of prior (non-cursed) maps representing (supposed) geographical splits of some conversational outcome or other, such as 1407: Worst Hurricane and 2108: Carbonated Beverage Language Map.

Transcript

This is one of 46 incomplete transcripts: Don't remove this notice too soon. If you can fix this issue, edit the page!

[A small panel showing Cueball pointing toward the left and Ponytail standing to his right overlaps the top of a much larger panel containing a map.]

Cueball: What's up with this weird landscape?

Ponytail: Oh, it was caused by ...

[The larger panel shows a map of the United States, with southern Canada, northern Mexico, and most of Cuba and the Bahamas visible as well. An inset at lower left shows Alaska along with part of northwest Canada, with a smaller inset showing Hawaii. International borders and coastlines are indicated in black, and state borders are indicated in gray. Red lines divide the United States into irregularly shaped zones (the red lines indicating zones do not cross into the neighboring countries, except in the Alaska inset), with each zone being labeled with red text. Each text label begins with "..." to indicate that it is the conclusion of Ponytail's sentence. The following are the labels used:]

[Main map:]

... a plate tectonics speedrun

... volcanoes

... megafloods

... a supervolcano

... geology

... water and time

... glaciers

... rivers

... continents colliding

... ???

... ongoing disputes between limestone and water

[On the main map, the label "... glaciers" appears three times in various places in the same contiguous zone that runs from Washington state to Maine. The label "... farming" appears twice, representing two separate zones, one that runs from Montana to Louisiana and the other that runs from New Jersey to Mississippi. The label "... geology" appears twice on the main map, representing two separate zones, one that runs from Washington state to Texas and the other being a roughly circular region mostly in southern Missouri and northern Arkansas.]

[Alaska inset:]

... geology

... volcanoes

... glaciers

[Hawaii inset:]

... volcanoes

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Discussion

Maybe it's more of statistics than exhibitions. --While False (speak|museum) 21:17, 3 October 2022 (UTC)

pixels-assembly-3.png

how is it 0 bytes?? i see that it is shown as 0 bytes on the wiki, but the file itself, when downloaded is 5kb! how???108.162.221.209 16:41, 4 October 2022 (UTC)Bumpf

If the question is how it can be written like that here, the answer is that I used the numbers of the wiki. —While False (speak|museum) 19:18, 4 October 2022 (UTC)

Sorry, should have made it more clear. Do you know why it is shown as 0 bytes on the file page? 172.70.134.103 12:37, 7 October 2022 (UTC)Bumpf

There's always the possibility that this is actually the Null image under the .png file format. Every other .png is defined by the delta required to display the desired graphic when starting from the baseline of this 'ur'-image, but if you ever wanted to display that graphic the undocumented format specifications allow you to omit all unnecessary bytes (including the magic header bytes) and it will happily produce its hardcoded "it's a PNG!" preprocessing template, which happens to be this image. Obviously, the PNG spec (and, ultimately, the original ancestor of the detailed source code tree for every subsequent implementation) was written before Randall ever got anywhere near to drawing this image so the chances are slim that he just happened to luck upon the exact image that happens to have a 100% compression rate because it just happened to consist of something Randall wanted to draw, and in the manner of Randall's artistry. But it's a non-zero likelihood that an arbitrary artist might draw exactly the same image as a purely arbitrary "index null" page's collection of pixels and so... This might not be the Best Of All Worlds, but there has to be some highly fortunate occurance to balance out all the unfortunate ones, statistically, and this is ours!

(Or maybe there's a minor bug/data-error in the way the wiki database serves the front-end webserver, but I can't ask you to believe something as trivially random as that!)) 172.70.90.245 15:03, 7 October 2022 (UTC)
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