3221: Landscape Features

2026-04-16T02:53:20Z

38.172.117.70:

{{comic
| number = 3221
| date = March 18, 2026
| title = Landscape Features
| image = landscape_features_2x.png
| imagesize = 537x454px
| noexpand = true
| titletext = '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 elements of the landscape in each region. For each area it names one major geological or human mechanism (plate tectonics, erosion, farming, 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 is overly-simplistic when trying to explain a complex landscape. A few phrases are longer, but still don't actually explain much, and some areas are just labeled "geology", which while lacking in explanatory power, is often solely responsible for some of the most striking landscape features. "Geology" is in fact poor label here, since almost all of the other causes (volcanos, glacial erosion, plate tectonics, etc.) are all elements of geology. Randall appears to default to "geology" as the cause in areas where the landscape is largely made of metamorphic or igneous rocks (mountainous areas) instead of some alteration of base rock features via volcanos, earthquakes, etc. However, the actual landscapes in these areas do have specific causes, as shown by the fact that the Appalachians are labeled as "continents colliding" not "geology". Similar more detailed explanations could have been given for other areas, for instance {{w|Laramide_orogeny|"one continent sliding under another"}} for the Rocky Mountains compared to "continents colliding" for the Appalachians.

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. The suggestion is that 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., {{w|Hawaii hotspot}}, {{w|Iceland}}, the {{w|Snake River Plain}} in Idaho, etc.) form from such mantle hotspots, so it's an easy go-to explanation for many of the geological features people are often most curious about. This idea was explored recently in [[3141: Mantle Model]].

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

===Table of regions===
{| class="wikitable sortable"
|-
! 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 are still rising today despite being far from any plate boundary, forming a dome with no clear tectonic cause.
|-
| Most of northern conterminous U.S.
| glaciers
| During the {{w|Last Glacial Period}}, this area was covered by {{w|Laurentide Ice Sheet|an ice sheet}} that left its marks on the landscape, in the form of {{w|moraines}}, {{w|eskers}}, {{w|glacial erratics}}, etc. This is most notable in Wisconsin where bluffs were formed due to the glacier movement.
|-
| Appalachian Mountains
| continents colliding
| {{w|Geology of the Appalachians|The Appalachian Mountains formed roughly 480 to 300 million years ago}} through a series of continent-continent collisions, culminating in the assembly of the supercontinent Pangaea. The primary collision involved ancestral North America (Laurentia) crashing into Gondwana (Africa/South America), resulting in a Himalayan-scale mountain range.
|-
| Mississippi and Ohio River Basins
| rivers
| The {{w|Mississippi River}}'s geology has a complex, 70 million year history involving massive sediment deposition, glacial activity, and tectonic shifting. Formed mostly by melting glaciers ~12,000 years ago, it drains a vast, shifting basin, depositing millions of tons of sediment in a massive delta and creating a vast, shifting alluvial plain. The {{w|Ohio_River#Geology|Ohio River's geology}} is similar.
|-
| Southeastern U.S.
| farming
| Landscape changes from {{w|cotton production in the United States}}, due to the presence of the {{w|Black Belt (geological formation)|Black Belt}}. From the perspective of landscape features, it would be more accurate to say that they were caused by "erosion" not "farming". The Atlantic Coastal Plain is made up of sediments and sedimentary rock eroded from the Appalachian Mountains over millions of years. The relatively flat landscape and loose fertile soils make farming both easy and productive respectively. Thus farming is a result of the landscape features, not a cause of them.
|-
| Southern Florida
| ongoing disputes between limestone and water
| Florida is a vast {{w|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 Floridian aquifer system.
|-
| Southern Missouri / Northern Arkansas
| geology
| The {{w|Ozark Mountains}}, which are composed primarily of ancient limestone and {{w|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.
|-
| {{w|Great Plains}}
| farming
| The lack of other major events left the terrain relatively level; as with the Southeastern U.S./Atlantic Seaboard (see above), the cause of the landscape here is erosion of the Rocky Mountains, with the sediments carried by rivers towards the Mississippi basin and creating a flat, even landscape. 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). European plowing techniques unsuited for the dry plains ultimately resulted in the {{w|Dust Bowl}}, a period of intense erosion and dust storms which reshaped the landscape, and as a response led to the {{w|Great Plains Shelterbelt}}.
|-
| Central Idaho / Yellowstone
| a supervolcano
| The {{w|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 {{w|Yellowstone Hotspot}}.
|-
| American West surrounding Idaho / Yellowstone
| geology
| [[3162: Heart Mountain]]
|-
| Immediately off of West coast up to the Four Corners
| volcanoes
| A combination of various {{w|volcanic field}}s of different origins, including {{w|Cascade Volcanoes}} in the Pacific Northwest, {{w|Albuquerque volcanic field}} in New Mexico, {{w|San Francisco volcanic field}} in Arizona, and {{w|San Juan volcanic field}} in Colorado.
|-
| Eastern Washington
| megafloods
| Most likely a reference to the {{w|Missoula floods}} and the {{w|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 {{w|Columbia River Gorge}} and flooding much of the {{w|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 {{w|Juan de Fuca plate}}, {{w|Pacific plate}}, and the {{w|North American plate}}, as part of the {{w|Ring of Fire}}. Could also be a reference to [[2061: Tectonics Game]].
|-
| Southwest Desert
| water and time
| The sedimentary rock layers exposed in the {{w|geology of the Grand Canyon area}} range in age from about 200 million to nearly 2 billion years old. Uplift of the region started about 75 million years ago during the mountain-building event creating the Rocky Mountains. The opening of the Gulf of California around 6 million years ago enabled a large river to cut its way northeast from the gulf. The new river captured the older drainage to form the ancestral Colorado River, which started to form the Grand Canyon. Wetter climates from ice ages starting 2 million years ago greatly increased excavation of the Grand Canyon, which was nearly as deep 1.2 million years ago as it is now.
|-
| Northern Alaska
| geology
| Northern {{w|Geology of Alaska|Alaska geology}} is dominated by the Brooks Range (a major Paleozoic mountain belt) and the Arctic Slope sedimentary basin, containing rich Paleozoic-Mesozoic rock sequences. The region is part of the Arctic Alaska–Chukotka Microplate, shaped by Mesozoic tectonic shifts, including the Arctic Ocean opening and the Brooks Range uplift.
|-
| Aleutian Islands
| volcanoes
| The Aleutian Islands are a continuation of the Alaskan {{w|Aleutian Range}}, and form part of the {{w|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 {{w|Glacier Bay National Park and Preserve|Glacier Bay National Park and Preserve}}) and western Canada has many glaciers that are still carving the landscape.
|-
| Hawaiian island chain
| volcanoes
| Hawaii, including the {{w|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 [https://www.google.com/maps/@34.0555574,-176.5939317,4904085m/data=!3m1!1e3?entry=ttu&g_ep=EgoyMDI2MDMxNS4wIKXMDSoASAFQAw%3D%3D here]. Volcanic fog from the {{w|List of volcanoes in the Hawaiian–Emperor seamount chain|three active volcanoes on the Big Island}} can often be seen on neighboring islands.
|}

===Features of each state, alphabetically===
* Alabama: continents colliding, farming, rivers
* Alaska: geology, glaciers, volcanoes
* Arizona: water and time, volcanoes
* Arkansas: geology, farming, rivers
* California: a plate tectonics speedrun, volcanoes, water and time
* Colorado: volcanoes, geology, farming
* Connecticut: glaciers
* Delaware: farming
* District of Columbia: either farming or plates colliding
* Florida: farming, ongoing disputes between limestone and water
* Georgia: continents colliding, farming
* Hawaii: volcanoes
* Idaho: a super volcano, geology
* Illinois: glaciers, rivers
* Indiana: glaciers, rivers
* Iowa: glaciers, farming, rivers
* Kansas: farming
* Kentucky: rivers, continents colliding
* Louisiana: farming, rivers
* Maine: glaciers
* Maryland: plates colliding, farming
* Massachusetts: glaciers
* Michigan: glaciers
* Minnesota: glaciers, farming, rivers
* Mississippi: farming, rivers
* Missouri: farming, geology, rivers
* Montana: geology, glaciers
* Nebraska: farming
* Nevada: volcanoes, geology, water and time
* New Hampshire: glaciers
* New Jersey: glaciers, farming
* New Mexico: volcanoes, geology, water and time, farming
* New York: glaciers, ???, continents colliding
* North Carolina: continents colliding, farming
* North Dakota: glaciers, farming
* Ohio: glaciers, rivers
* Oklahoma: farming, geology
* Oregon: a plate tectonics speedrun, volcanoes, megafloods, a supervolcano, geology
* Pennsylvania: glaciers, rivers, continents colliding, farming
* Rhode Island: glaciers
* South Carolina: continents colliding, farming
* South Dakota: glaciers, farming
* Tennessee: continents colliding, rivers
* Texas: farming, geology, water and time
* Utah: geology, volcanoes
* Vermont: glaciers
* Virginia: continents colliding, farming
* Washington: megafloods, a plate tectonics speedrun
* West Virginia: rivers, continents colliding
* Wisconsin: glaciers, rivers
* Wyoming: a supervolcano, geology, farming

==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

{{comic discussion}}<noinclude>

[[Category:Comics with color]]
[[Category:US maps]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Geology]]
[[Category:Volcanoes]]

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3221: Landscape Features