Nicolas Steno, a Danish scientist renowned for his contributions to geology, is often credited with laying the foundational principles of stratigraphy. Initially focusing on anatomy and medical sciences, Steno’s keen observational skills led him to a profound realization: the tooth-like objects found in rock formations were in fact fossilized remains of ancient creatures, akin to the teeth of a dissected shark.
In 1669, Steno published “Dissertationis Prodromus,” a seminal work in which he outlined the core principles of stratigraphy that remain central to geology today. These principles include the Law of Superposition, suggesting that in a sequence of layered rocks, the youngest layers sit atop older ones; the Principle of Original Horizontality, proposing that rock strata were initially formed horizontally; the Principle of Lateral Continuity, asserting that rock layers extend continuously over a large area; and the Principle of Cross-Cutting Relationships, which states that geological features that cut through other layers are comparatively younger.
These principles, foundational to the field of geology, challenged the then-dominant Aristotelian view and suggested the Earth’s much greater antiquity. Steno’s insights, though seemingly intuitive now, were groundbreaking and contentious during his time. They not only illuminated the process of fossilization but also hinted at the vast timescales of Earth’s geological history, a concept that would only be fully appreciated centuries later. Steno’s work marks a pivotal moment in the evolution of geological science, influencing the way we understand our planet’s past and its dynamic processes.
