Extensional tectonics

Extensional tectonics is concerned with the structures formed, and the tectonic processes associated with, the stretching of the crust or lithosphere.

The types of structure and the geometries formed depend on the amount of stretching involved. Stretching is generally measured using the parameter ${\displaystyle \beta }$, known as the beta factor where

${\displaystyle \beta ={\frac {t_{0}}{t_{1}}}}$

${\displaystyle t_{0}}$ is the initial crustal thickness and ${\displaystyle t_{1}}$ is the final crustal thickness. It is also the equivalent of the strain parameter stretch.

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