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Landscape Features
'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
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

Explanation

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

The title text plays off the fact that a large part of geology 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
Near Mississippi & Ohio Rivers rivers
Southeastern U.S. farming
Southern Florida ongoing disputes between limestone and water Karst topography
Southern Missouri/Northern Arkansas geology Ozark Mountains
Central column of U.S. farming This area loosely corresponds to the Great Plains. 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 contigious Rocky Mountains. It was formed by the movement of the contenential plate over the Yellowstone Hotspot.
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 ht 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.
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 volcanos, 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.

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



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