Researched
Stratigraphy (Steno)
Steno's law of superposition (1669): in undisturbed layers, deeper means older, the base for dating earth and sites.
Open in the interactive tree →Nicolaus Steno reasoned from rock and fossil layers in Tuscany that strata are laid down in sequence. Geologists such as Hutton and Smith, and archaeologists excavating in layers, use the principle to order events in time.
Prerequisites
- Scientific Method~1600-1620
Unlocks
- Geology and deep time1788Hutton and Smith read rock layers using Steno's law of superposition
- Three-Age System1836