So, why is there so much petrified wood here? There isn’t a tree for miles, especially one that resembles the petrified wood found here. Around 225 million years ago, during the Triassic Period, Utah was much closer to the equator and coastline, and the climate was also much warmer. At this point in Utah’s ancient history, the topography was much flatter, so the waterways were sluggish, yet prevalent due to the rain-saturated, volcanic mountains to the south. Northwest-flowing rivers and streams transported nutrient-rich volcanic ash and soil throughout Utah, and blanketed the surrounding plains as they flooded often.
Large conifer trees grew in this fertile soil, but ironically, the same mountains that provided these lush tree-growing conditions probably led to their demise as well. Violent eruptions of ash overwhelmed the region and its waterways with too much silica, killing the trees, and subsequently burying them in the surrounding ash-laden mud and water that protected and preserved them for later discovery.
These prehistoric conditions are evident in the petrified wood-rich mudstone layers known today as the Petrified Forest Member of the Chinle Formation. In addition to an abundance of petrified wood, this 150- to 300-foot-thick layer of rock is found sporadically throughout the Colorado Plateau and is distinguished by its dull-pink layers, “popcorn” weathering texture, and resemblance to badlands. At Wolverine Petrified Forest, the highest concentration of petrified wood is contained within an approximately 10- to 30-footthick deposit. This rock layer is easily erodible and forms an easily-distinguishable slope beneath the brown-red cliffs of the Wingate Sandstone.