# Plate Tectonics
Confidence: high
Last verified: 2026-05-22
Generation: ai_assisted


## TL;DR

Plate tectonics (theory accepted 1960s) explains Earth's surface dynamics: the lithosphere is broken into tectonic plates that move on the semi-fluid asthenosphere. Boundaries: divergent (pull apart, mid-ocean ridges), convergent (collide, mountains/trenches), transform (slide past, San Andreas Fault). Drives earthquakes, volcanoes, mountain formation.

## Core Explanation

Historical: Alfred Wegener proposed continental drift (1912) but couldn't explain mechanism. Seafloor spreading (Hess, 1962) + magnetic striping provided evidence. Plates move 1-10 cm/year (fingernail growth speed). Ring of Fire: Pacific boundary with high volcanic and seismic activity. India-Eurasia collision created the Himalayas (ongoing, ~5mm/year uplift).

## Further Reading

- [Plate Tectonics: An Insider's History (Naomi Oreskes)](https://www.hachettebookgroup.com/titles/naomi-oreskes/plate-tectonics/9780813341323/)