scales and sometimes little thorns. It all reminded him of the skin of pineapples.
“They look kind of like trees,” he finally said.
“They are trees,” McNair said, nearly breathless with it all. “Permian trees. Good God in heaven, a forest of trees, still rooted, still in their upright living positions after 250 million years.”
Breed and Maki just looked at each other.
“Doc,” Breed said, knocking on one of them. “They’re made of stone.”
“They’re petrified,” Boyd said. “Just like those bones. They’re fossils.”
“Exactly,” McNair said.
All of them got the significance of it now: a forest of prehistoric trees.
And there had to be hundreds of them.
As they explored around, they found some that were no taller than a man and others that must have been eighty feet when they were alive, and still others that were probably hundreds of feet that disappeared right into the rock overhead. Some were just trunks, others had been snapped off thirty feet up, petrified logs and branches and deadfalls lying about. But many were nearly intact, their limbs still extant. Not only had the trees themselves been fossilized, but the loam around them. Heaps of fallen leaves were as petrified as the trees they fell from.
Boyd found it hard to take it all in, that immense, maze-like run of trees like the masts of ships.
Maki just didn’t get it, though. “How does a tree turn to rock?”
Breed said, “It’s like out in Arizona, the Petrified Forest. I been there. Ain’t you ever heard of that, Maki?”
“Oh yeah, sure.”
McNair told them that the trees in the Petrified Forest in Arizona were from the Triassic, but what they had here was much older. Much, much older. In Arizona, some of the trees were still rooted as these, but many had been washed by prehistoric seasonal floods into sandy river channels where they were buried in gravel and sand rich in volcanic ash.
“The process is called permineralization,” McNair explained. “I imagine this entire area was in some sort of lowland swamp or valley during the Permian. A flash flood probably turned that valley into a bog or a muddy lake. Hence, oxygen which causes oxidation and rot, was kept away. These trees were buried in water and sediment. What happens next is that the trees either disintegrate or are compressed into coal over a period of millions of years, or, in this case, they permineralize. Minerals gradually replace the woody tissues and you have petrified trees.”
Breed said, “Yeah, but this is better than the Petrified Forest. A lot better.”
“Yes. Yes, it is. This entire forest must have been locked in that bog and the entire thing, through the passage of thousands or even hundreds of thousands of years must have dried up, but the sediment that enclosed it turned to stone, capturing our forest as we now see it. Nearly intact.”
McNair said that much later, whatever geologic upheaval swallowed up the Permian strata and sank it deep into Precambrian rock, brought the forest here as well. Through the ages, waters must have eroded the rocks away and exposed what they were seeing now.
Maki was interested. “There’s nothing like this anywhere? Not even Arizona?”
McNair shook his head. “A few years ago, a nice stand of petrified Permian trees were discovered near the Beardmore Glacier in Antarctica. But nothing like this.”
Some of them rose up out of the rock on spidery tangles of fossilized roots and others had trunks so huge that three men could not have circled them with their arms. McNair said there were both conifers and deciduous trees in this forest. They were looking at cycads and gymnosperms and seed ferns, an amazing variety. He pointed out short trees with fern-like fronds that were called Archaeopteris, the progenitors of modern pines. Something called a Dicroidium that looked more like a large houseplant than a tree. There were primitive Ginkgoes with broad, fanlike leaves, cycads that looked much like