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How do the coastlines of eastern South America and western Africa support the idea of Pangea?

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Permian paleogeography — Pangea Distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins near the end of the Permian Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.

The observation that the coastlines of eastern South America and western Africa appear to fit together like pieces of a puzzle was a foundational clue in the development of the continental drift hypothesis.12

While early observers like Francis Bacon and Alexander von Humboldt noted this visual congruency, critics long argued that such shapes were merely the result of coastal erosion and sea-level changes. This skepticism was largely addressed in 1964 through a computer analysis by Sir Edward Bullard, which demonstrated an impressive fit of these continents at the 1,000-metre (3,300-foot) depth contour. This depth provides a much more accurate approximation of the true continental edge than the modern shoreline.342

Beyond their physical shape, the connection is supported by geological evidence:
* Matching Geology: Ancient rock belts and crystalline massifs on opposite sides of the South Atlantic correspond closely in age and composition, indicating they were once part of a single assemblage.32
* Stratigraphic Evidence: The earliest marine deposits along these coastlines are Jurassic in age, suggesting the Atlantic Ocean did not exist prior to the fragmentation of Pangea.2