FE Meme
Abyssal Plains Cover 50%: How Is That Flat on a Ball?
#293: Abyssal plains are the flattest places on Earth and cover more than 50% of the surface, so that much flat area cannot exist on a ball Earth.
The Meme
Educational-style graphic: abyssal plain cross-section beside coast, macro text on flat ocean floor and footer "Earth is flat! Research it!"
Why It Spreads
The infographic borrows textbook language about abyssal plains and pairs it with a bold percentage, so the footer punchline feels like a logical trap. Most viewers never picture those plains as smooth sediment on a curved geoid, so "50% flat" reads as half the planet being a level sheet.
What It Gets Wrong
Abyssal plains are geologically smooth relative to nearby seafloor relief, not flat in Euclidean space across planetary scale. They still sit on Earth's curved geoid where local "level" follows gravity toward the center; over 100 km, h ≈ d²/(2R) with R ≈ 6371 km predicts on the order of 80 cm of bulge, invisible in a cartoon cross-section. Calling half the surface "flat" swaps local smoothness for zero curvature, which is inconsistent with sonar bathymetry and gravimetric geoid models. TestTheGlobe's Water Finds Level Means Flat and TestTheGlobe's Curvature Calculator walk through the observations and predictions this image skips.
The Debunk
Smooth abyssal plains on a geoid are compatible with a near-spherical Earth; h ≈ d²/(2R) still predicts measurable ocean-scale curvature over tens of kilometres. Equating local seafloor smoothness with planetary flatness is inconsistent with bathymetry and gravity surveys. Use TestTheGlobe's Curvature Calculator to compare the meme's claim with a measurable prediction.
- TestTheGlobe's Water Finds Level Means Flat: "level" on oceans means perpendicular to gravity on a body with R ≈ 6371 km, not a Euclidean plane across half the planet.
- TestTheGlobe's Curvature Calculator: over 10 km of open water, h ≈ d²/(2R) predicts on the order of 8 m of midpoint drop, far more than any abyssal-plain cartoon measures.
- The infographic labels abyssal plains "the flattest places on Earth" but never logs baseline distance or drop, so the 50% statistic cannot falsify either shape model.
- TestTheGlobe's No Curvature Is Visible: sonar and gravimetric maps show seafloor relief on a curved geoid, not a single flat sheet covering half the surface.