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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, 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 Florida is a vast karst landscape formed by the dissolution of underground limestone and dolostone bedrock by acidic rainwater, resulting in a terrain characterized by sinkholes, springs, caverns, and disappearing streams. This soluble bedrock, formed from ancient marine deposits, covers much of the state, directly connecting surface water to the Floridan aquifer system.
    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 replaced 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

    [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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