That’s So Second Millennium

Episode 024 - Geology after Steno: Diluvialism, Neptunism, and Vulcanism

September 10, 2018

With acknowledgments to A. Hallam and his Great Geological Controversies

18th century: it becomes more and more possible and even fashionable to discard the minimalist Scriptural timescale
Nevertheless, Western thought is so thoroughly steeped in Christianity that every major development is either an extension (subconscious or not) of a Christian theme or a deliberate rejection of one.

- Decay and refutation of the Genesis minimalist paradigm for interpreting geology.
    - "Diluvialism", the theory that either Noah's Flood as a global phenomenon c. 3000 BC or a similar worldwide flood at a more loosely defined point in Earth's history
- Competitor paradigms in early geology, their conceptual and thematic relationships to Noah's Flood.
    - Neptunism, vulcanism, plutonism

The difficulty of even finding good outcrops to come to solid conclusions about geological questions

Controversy between the "neptunists", "vulcanists", and "plutonists" revolves around a very limited number of observations at key field localities in west-central Europe:
    Flat-lying basalts in Saxony sandwiched into a sedimentary sequence
    Volcanoes in Italy, especially Vesuvius (the most accessible and famous)
    Extinct but still recognizable volcanoes in Auvergne, in France, where basalt cones and flows overlie huge thicknesses of granite