Plate Tectonics

Source: J. Tuzo Wilson, Nature 207, 1965; Alfred Wegener, 1915; Harry Hess, 1962; McKenzie & Parker, 1967; Morgan, 1968 Institution: Multiple

Finding

Earth’s lithosphere is divided into rigid plates that move on the asthenosphere. Plates are created at mid-ocean ridges and destroyed at subduction zones. The process drives volcanism, mountain building, earthquakes, and long-term element recycling. The Wilson Cycle describes the opening and closing of ocean basins over hundreds of millions of years. Wegener had the correct observation (continents move) but the wrong mechanism; he was rejected for 50 years until seafloor spreading was discovered independently.

Pattern Mapping

Proportion — Dynamic equilibrium: new crust is created at approximately the same rate it is destroyed. The surface area of Earth does not grow or shrink. Creation and destruction balanced over geological time.

Alignment — The theory unified previously disconnected observations: continental fit, fossil distributions, paleomagnetic reversals, earthquake distribution. Evidence was aligned before the theory recognized the alignment.

Humility — Wegener had the pattern without the mechanism. His rejection was not unreasonable given available physics. A correct observation without a viable mechanism is legitimately vulnerable to skepticism.

Connections

Status

Established geophysics. See Oreskes, ed., Plate Tectonics: An Insider’s History (2003). The mapping to the five properties is this project’s structural interpretation.


The mapping to the five properties is this project’s structural interpretation.