Significance of Uniformitarianism
Uniformitarianism (which also came to be known by the term gradualism) competed for acceptance with catastrophism and eventually displaced it. But you might be asking yourself: Why was it such a big deal?
The answer is that Hutton was the first person to recognize (at least in published work) that we could understand much about how geologic features (such as valleys, sedimentary rocks, and mountains) came to be by observing the events of the present day. Uniformitarianism gave us a tool to interpret the geologic past. In fact, geologists sometimes summarize the concept in the phrase: The present is the key to the past.
The concept is applied to all types of geologic processes. For example, rivers erode valleys and build deltas gradually. Mountains rise at an imperceptible rate and erode just as slowly. Stalactites require uncounted years to form (as do the caves in which they are found). Rocks weather bit by bit, and the resulting sediment is deposited incrementally, layer upon layer, to eventually become sedimentary rocks.
The other big idea inherent in uniformitarianism is that Earth is a very old place. For slowly operating processes (like river deposition) to create geologic features (like a delta) required a much more ancient age for Earth than catastrophism assumed. So, the idea of the immensity of geologic time (sometimes called deep time) also began with Hutton's work.
Modern View of Uniformitarianism
Modern geologists interpret the idea in a slightly different way than it was originally conceived, but it is still an indispensable concept in interpreting the geologic history of our planet.
As more geological studies were done, geologists discovered that while many processes do indeed act gradually, some changes happen rather quickly. Good examples are the reshaping of a coastline by a tsunami, deposition of mud by a flooding river, the devastation wrought by a volcanic explosion, or a mass extinction caused by an asteroid impact.
The modern view of uniformitarianism incorporates both rates of geologic processes. For the most part, geologic change occurs slowly, but huge events or major upheavals, while rare, certainly have altered the shape of our planet over geologically short time spans. That pattern is now a part of the overall concept since such things have happened throughout geologic time.
Some geologists suggest that we no longer need such a concept to explain our geologic past. Many others believe the idea that long-acting processes play a significant role in shaping the earth and is still a valuable framework for understanding the planet. Uniformitarianism may have changed (slowly), but it's still around.
Uniformitarianism is the name given to the idea that natural processes behave more or less in the same way today as they have throughout the past, and will continue to do so in the future. It is sometimes summarized by the statement that the present is the key to the past, and it was a founding principle for the science of geology. Catastrophic events have and continue to occur, and geologists now accept those upheavals to be a part of the overall concept.
Catastrophic events can reshape the planet.
|Points to Remember
|Uniformitarianism - refers to the idea that natural processes behave more or less in the same way today as they have throughout the past, and will continue to do so in the future
|Importance - we can understand much about how geologic features (such as valleys, sedimentary rocks, and mountains) came to be by observing the events of the present day
|Modern view - geologists presently see most events do occur over long periods of time, while a few are catastrophic events that impact the planet's shape more quickly
When this video concludes, we will be ready to:
- Describe what uniformitarianism is
- Identify how geologists developed this theory
- Explain the modern view of uniformitarianism