Geology Reference
In-Depth Information
resulting in a second round of cavern collapse that produced modern topography and the
tipped-up rock layers within. It was Steno's way of making sense of what he observed giv-
en his faith in the historical reality of Noah's Flood.
Steno's six-stage model for the formation of the landscape around Florence, involving: (1) precipitation of fossil-free
sedimentary rocks into a universal ocean; (2) excavation by fire or water of great subterranean caverns beneath Earth's
pristine surface; (3) collapse of undermined continents to produce a great flood (Noah's Flood); (4) deposition of new
layered (sedimentary) rocks containing fossils in inundated valleys; (5) continued undermining of younger rocks in val-
leys; and (6) another round of collapse to create the modern topography.
Steno's version of Tuscan geologic history fit neatly into the traditional interpretation
of Genesis as historical truth. But where did the floodwaters come from? Steno's theory
combined various natural causes to explain Noah's Flood. Debris from Earth's collapsed
outer crust blocked the passages that pushed seawater back up into the mountains. While
