Petrified Forest: Beauty, Mystery, and Catastrophic History
Luke Wayne – March 07, 2025
The splendor and importance of this fossilized arbor is hard to overstate. But how did it get here?
Arizona’s Ultimate Rock Garden: The Petrified Forest
Roughly two hours down I-40 East from Flagstaff, or about fifty miles before you reach the New Mexico border, you’ll find one of Northern Arizona’s true gems—the beautiful mystery of Petrified Forest National Park. In 1906, when the passing of the Antiquities Act first gave U.S. Presidents the power to create National Monuments, Petrified Forest became one of Arizona’s very first landmarks to receive that designation. It would take another two years before even the Grand Canyon was afforded that protection! (Of course, Grand Canyon was promoted to a full-blown National Park a mere decade later in 1919, while Petrified Forest had to wait until 1962 for that honor.)
The landscape is dotted with the ancient remains of Native American pueblos and rock art, testifying that we are far from the first to enjoy its beauty and marvel at its secrets. It became a tourist stop by railroad in the 1880s and is also the only National Park to contain a portion of the original Route 66. It now sits right on today’s Interstate 40, where roughly 600,000 visitors drive out to see it each year. It seems people in every era have desired access to this incredible natural wonder. While the rainbow rock layers of the Painted Desert and the mineralized bones of giant reptiles add to its grand mystique, the name of the park suggests its real draw: the vast collection of gigantic and stunningly petrified ancient trees that adorn the whole region. The splendor and importance of this fossilized arbor is hard to overstate. But how did it get here?
How Petrified Wood Forms
To understand the origin of the Petrified Forest, it is important to grasp the basics of how petrified wood forms. Petrified wood is a type of fossil. Wood “petrifies” when specific minerals (most often silica) seep into the wood and either replace the organic compounds in the wood, fill in the gaps between the wood’s structures (making a sort of mineral cast of the wood), or both. For this to happen, the wood must be both protected from decay and exposed to the minerals in such a way that they penetrate deep within the wood’s porous structure. This requires:
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- An oxygen-free environment
- The presence of water with the right minerals dissolved in it.
The most common source of silica and other appropriate minerals is from volcanic eruptions, which can also be what buries the trees. While other organic objects can petrify, wood is especially suited to the process because it is more resistant to rotting and is specifically designed for water to flow through it carrying dissolved nutrients. When the tree is alive, its cell walls form a plumbing system to draw water up from the soil through the trunk and branches to even the highest leaves.
As the silica-rich water seeps through the dead log, these cell walls are often the first thing the minerals replace. This is why some petrified wood still preserves the vivid details of the original tree down to the tiniest grain, so much so that you may not be able to tell the difference between wood and fossil without touching it! Along many of the trails in Petrified Forest National Park, the shattered bits of fossil trees look exactly like fresh mulch. In other cases, trace metals and quartz crystals transform the former tree into a vibrant array of new colors and textures, giving rise to favorite stops in the park like “Rainbow Forest” and “Crystal Forest.”
Once the minerals have replaced much of the tree’s cellular structure and filled in its empty spaces, any remaining organic material either decomposes or remains trapped and preserved in its crystal prison.
A Petrified Forest?
Alright, so the term “forest” might be a little misleading. After all, none of the trees are standing up. They are quite numerous, but not so plentiful as to look like a densely wooded area. Still, we are talking about a lot of large trees petrified in the same vicinity. It is relatively easy to imagine how a volcanic eruption (or a local flood or mudslide in a previously volcanic region) might knock over and deeply bury a tree or two in a silica-rich environment. But a petrified forest, even using the term loosely, is obviously more than just a few logs. Petrified forests are regions that contain large numbers of fossilized trees in the same area, and often in the same set of rock layers. This requires a bit more of an explanation.
The popular model you will often hear for Petrified Forest National Park is that, in the distant past, this desert used to be a marshy region through which flowed a massive river system. Trees that died and fell over would often be carried along downstream, eventually joining with other such trees to form log jams that the river would then bury in accumulating sediment. Since the region was once volcanically active, these buried log jams would sometimes become saturated in the right minerals below ground in the water table.
Over time, many of these logs slowly became the fossil trees we enjoy today. So, at least, goes the mainstream model. The mineral content of the petrified trees and the colorful layers of mudstone in which they are buried make it clear that these trees were buried and preserved due to a period of violent volcanic activity and the flow of a lot of water. But that evidence may point to something other than an ashy swamp.
A Look at the Evidence
Far and wide, high and low, the evidence points not to the imperceptibly slow effects of eons of time, but rather the catastrophic impact of a single cataclysmic event: the biblical Flood of Noah’s day!
Most scholars assume an ancient marsh and a massive river system for understandable reasons. As mentioned above, the region is primarily made up of layers of crumbly mudstone (with occasional sections of harder sandstone). Within these mudstone layers, we find not only petrified trees but also numerous fossils of ferns, amphibians, fish, massive crocodilian reptiles, flying pterosaurs, and several dinosaur-like beasts whose bones one can enjoy at the Rainbow Forest Museum near the park’s south entrance. Mud, ferns, giant crocodiles; at first glance, the suggestion of a boggy river environment slowly burying logs is a rational hypothesis. Still, there is perhaps a better explanation.
The rock layers that make up Petrified Forest National Park are part of the Chinle Formation. This vast expanse of sedimentary rock stretches across Nevada, Utah, Colorado, Arizona, and New Mexico. Adjacent to the Chinle Formation is a remarkably similar set of layers known as the Dockum Group, which spread out from New Mexico across Western Texas and through portions of Colorado, Kansas, and Oklahoma. These two formations are considered to have formed at about the same time and are so much alike (and contain such similar fossils) that some geologists believe that they are, in fact, one large formation. Thus, one needs either to explain two remarkably similar and equally massive scenarios happening simultaneously to produce these twin formations or else a single especially vast scenario to explain one huge formation. Either way, the sheer breadth and scale of it all points to something larger than a river.
Furthermore, we not only find evidence by looking wider but also by looking deeper. If we examine the rock layers below the Chinle Formation, like those visible in the Grand Canyon, what do we find? The evidence indicates that layer after layer was laid down in a single, massive event involving earth-shaking volcanism and massive amounts of water, just as we see in the Chinle and its petrified trees. The very fact that the Chinle is filled with the numerous and varied fossils of massive trees, gargantuan beasts, and beautifully preserved ferns (which can wilt in minutes if not swiftly buried) fits with the rapid, widespread burial of a catastrophe. Mass fossil graves are not formed through slow, gradual processes. Far and wide, high and low, the evidence points not to the imperceptibly slow effects of eons of time, but rather the catastrophic impact of a single cataclysmic event: the biblical Flood of Noah’s day!
A global flood unleashed by the breaking open of the “fountains of the great deep” has the capacity to explain:
- The massive amounts of mud and silt needed to create a formation as large as the Chinle Formation/ Dockum Group
- Sufficient water to uproot, transport, rapidly bury, and preserve a forest’s worth of trees
- The volcanic mineral content needed for the petrification process
- The simultaneous rapid burial of other plants and animals
- The context of the Chinle in relation to the layers above and below it in the larger geological column
The global Flood has the explanatory power to make sense of the whole body of evidence, not merely in the Petrified Forest itself, but in the entire set of rock layers in which it is found spanning across much of the North American continent!
But Can Petrified Wood Form Fast Enough?
For the biblical Flood to be the explanation for all of these fossilized trees, the wood would need to petrify much faster than we are accustomed to thinking. Noah’s flood was only a few thousand years ago. Doesn’t petrified wood take hundreds of thousands or even millions of years to form?
The simple answer is, no. Under the right circumstances, wood can mineralize remarkably quickly. In a laboratory, scientists have been able to produce petrified wood in mere hours. In the hot springs of Yellowstone, researchers have observed wood petrifying naturally in only a few years. The speed at which wood petrifies is highly variable. Given the right conditions, the process can occur in plenty of time to fit within the biblical account of history. And in the mineral-rich, volcanic waters and sediments of the global Flood, ideal conditions for petrification were readily at hand!
Conclusion
Arizona’s Petrified Forest was formed by a process that involved:
- Significant volcanic activity
- Massive amounts of moving water
- The transportation and rapid burial of numerous large trees along with other diverse organisms
- The laying down of mud, sand, and silt across a sizable portion of the current United States.
This evidence fits incredibly well with the ancient, worldwide Flood recorded in the Book of Genesis. When we start with the Bible, the world around us makes sense!
To explore this issue further, check out the fantastic article over at Answers in Genesis by our good friend Dr. Andrew Snelling. If your church or school group would like to explore this marvelous landscape for yourselves, reach out to us about our Large Group Tours of the Petrified Forest!
