Uniformitarianism is dead! Long live catastrophism!

I had something pop up in my google alerts this morning, and it pointed to this article on creation.com. I don’t recommend clicking or reading unless you want a helping of brain hurt this early in the day. The part that was of interest to me reads:

By way of illustration, consider geologic formations in the Great Basin of the western United States. The vast horizontal layers of hydraulically deposited sedimentary rock are said to take long periods of time to accumulate, based on the assumption that the rate of deposition was always similar to that observed today in a typical river delta. This concept of uniformity may seem like a reasonable starting point when considered abstractly, but no steady-state river flow could possibly cover such a vast area; neither would it produce the violently buried and mangled bodies found fossilized in many rocks of the region. The present-day erosion conditions applied uniformly in the past could not account for the unusual formations of the Grand Canyon, mesas, badlands, and other canyons. By contrast, the catastrophic processes observed during and following the eruption of Mount St. Helens in the Cascades of Washington state produced a scale model of the Grand Canyon in a very brief period of time. Sediments were rapidly deposited and then suddenly eroded by pyroclastic steam, water, and mudflows in the area northwest of the summit. Now the canyon walls resemble others that are assumed to be of great age, even though they are known to be [merely decades] old.2

The point to be recognized is that science deals with observations of present states and processes, and can only discuss the prehistoric past. In the example of geologic formations of the Great Basin, the assumption of uniformity can be contrasted with a model of catastrophic tectonic, volcanic, and hydraulic activity that would accompany a global cataclysm such as the great Flood of Genesis. The observed eruption of Mount St. Helens demonstrated that rapid processes can produce effects commonly believed to require long periods of time, and thus gives credence, if not preference, to the concept that the earth’s geology did not require long periods of time to develop. Many puzzling formations can only be explained through cataclysmic forces. Similarly, other methods of estimating the age of the earth or of the universe apply assumptions about processes and rates that extend into the distant past. Regardless of how apparently compelling such dating methods may appear to be, the fact remains that they are built on assumptions that must be critically questioned and evaluated.

Wall of text crits you for 2K! (…sorry, little World of Warcraft joke there. You can slap me later.)

Basically, what he’s saying is:
– Strictly applying the observed depositional/erosional conditions of today to events of the past doesn’t explain everything perfectly.
– There’s evidence for catastrophism.
– Hey, there’s a canyon by Mt. St. Helens that’s like a scale model of the Grand Canyon and it formed in a matter of decades. Suck it, uniformitarians!

I’m not going to get in to the specific third claim here, because Talk Origins has already addressed it, and so very concisely. If someone actually stumbles upon this little bottled note in the vast oceans of the internet and would like me to get in to more detail than that, I definitely can.

What I really want to talk about are the first two points, because those are constantly belabored by creationists. There’s evidence for catastrophism! Incremental change doesn’t explain everything!

What this boils down to is a straw man, a disingenuous mischaracterization of uniformitarianism, and how geologists apply the principle.

So, what is Uniformitarianism, you ask? It’s the principle that as today, so in the past. It’s the assumption that the same laws of physics we’re operating under today are the same laws of physics there were over the billions of years of Earth history. It’s the principle that processes as we see and understand them today occurred in the same manner and to the same effect in the past.

What Uniformitarianism is NOT is the strict application of today’s processes to the past. It is not the assumption that if we cannot observe it in person, and in real time today, that it could not possibly have happened in the past.

If you were to apply Uniformitarianism in that manner, for example, you’d have no explanation for komatiite, which is an extrusive igneous rock from the Archean period. There are no rocks forming today that look like komatiite or have its same composition, because conditions on the Earth have changed over the last 2.5 billion years. In the Archean, the Earth was producing so much heat internally that it could produce a full melt of the mantle, and thus komatiite. Today, there’s only enough internal heat to allow for a partial melt, and thus we end up with basalt. So does that mean komatiite is impossible, because the Earth’s volcanoes aren’t spewing it forth today? No. And we understand why. Conditions have changed, following the same laws of physics and chemistry that we operate under today.

I’ve yet to meet a geologist who follows Uniformitarianism the way creationists like to envision it. Rather than assuming that nothing outside of the geologic processes of today could have possibly applied in the past, we instead use those processes to inform our understanding of the past. Creationists like to whine (yes, whine) that geologists refuse to accept that catastrophic events occur, because we’re uniformitarian sticks in the mud. This could not be further from the truth. Anyone that’s done even basic reading on volcanoes, earthquakes, glacial outburst floods, or landslides knows that catastrophic events can and do occur. We just don’t buy that your catastrophic event could occur because you’re incapable of explaining it without a flood (har har) of special pleading.

My favorite example of the reality of catastrophic geological events comes in the relationship between modern glacial outburst floods and the formation of the Channeled Scablands in Washington. (This was also my presentation topic for Skepticamp in Colorado this year.) The current scientific consensus about the Channeled Scablands is that they were formed by a massive, dare I say catastrophic, series of floods. The Cordilleran Ice Sheet formed an ice dam across the Clark Fork River, backing all that water up over a period of years to form Lake Missoula. (The old Lake Missoula bed is where present day Missoula, Montana is located. You can still see the old lake shore deposits in the hills.) When the lake became sufficiently big to partially float the ice dam (it was made of ice, after all) the dam failed catastrophically and the lake was able to drain in a matter of days. (If you’d like to read more about these giant floods, Discover the Ice Age Floods and Ice Age Floods Institute are a couple of good sites to start with.)

This theory of the Scablands formation is actually very new, and there was a lot of scientific pulling of hair and scratching at faces over it. This is obviously also not an event we have any chance of observing today, since it’s not the ice age, and the Cordilleran Ice Sheet is long gone. (Something for which the residents of western Washington State are no doubt grateful.) However, in modern times we can still observe glacial outburst floods of a much smaller variety, such as the floods from Hidden Creek Lake at the Kennicott Glacier. Research on these modern floods has certainly led to better understanding of how the ancient Lake Missoula/Cordilleran Ice Sheet floods worked.

Or look at it this way: Have we directly observed a Chicxulub-type impact event? I sure hope that we never will. But we’re still doing a lot of work on that and other impact sites, and we are using Uniformitarian principles, since the laws of physics that caused that meteor to hurtle into our planet are still most definitely in force.

So, Dr. Ashton, you are right. Strict adherence to uniformitarianism as you paint it explains very little of the past. And catastrophic events do occur. Strangely enough, geologists know and understand this concept well, and it’s created a robust body of evidence and theory to form our picture of the Earth’s 4.5 billion year geological history.

Unfortunately for you, we’re just a little too uniformitarian (the real sort) to buy the special pleading that the laws of physics have changed so that you can have your 6000 year old Earth.

Leave a Reply