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On Nov. 7, the Arizona Cycling Association had its state championships at Wren Arena in Fort Huachuca. The White Mountain Composite Biking team, at left, participated and three members earned spots in the award podium. Keziah Gesner took second place for girls JV 2, Sedona Rodriguez took third for girls JV 2, and Dylan Hewitt took fourth for boys JV 1. The team overall took third in Division 2 out of 43 teams. The team includes, not in order, coach Christy Church, Connor Bierer, Dylan Heuett, Lucas Randall, Keziah Gessner, Dodge Hatch, Sedona Rodriguez, Phoenix Rodriguez, coach Rusty Church, Tytan Kakavas, Landen Henderson, Keevan Church and Timothy Kersnowski. Not pictured are Adalie Sarchet, Kai Fenstermaker, Tyler Lunt, Dean Marshall and Trevor Owens.

At peace in the Triassic’s graveyard

PETRIFIED FOREST NATIONAL PARK — I am sitting on the grave of a lost world.

It’s beautiful – all blue and gray and red.

The sun is setting, so the shadows have grown long, and they are filled with mystery. The hills are smooth and hollowed, like the curve of hip and shoulder and thigh.

My bottom hurts.

So I shift and find the piece of petrified wood on which I have ensconced myself. I did not notice the chunk of an extinct conifer when I sat down in the powdery, reddish dirt of the Chinle formation, here in the heart of the Petrified Forest.

I come here whenever I need to put things in perspective and contemplate the nature of time and death and change. Seems like I do it more often these days – with so much of my own time already spent.

On this trip, I am working to process the deep secrets revealed by the 220-million-year-old soils, as presented in a research paper published in the Journal of Sedimentary Research. The study by seven scientists from varied institutions links mass extinction, plate tectonics and climate change to this colorful dirt.

The paper represented a breathtaking effort to explain what happened here as the super continent Pangea broke up and the light crustal rocks went drifting off into their present positions.

The breakup of Pangea was driven by the slow-motion boiling of rock far beneath the surface, which caused a fit of earthquakes and volcanoes lasting for millions of years.

Those laboriously collected, exhaustive analyzed ancient soil samples revealed a dramatic picture, meticulously documented in the 12-page paper by researchers from Baylor, Massachusetts Institute of Technology, Petrified National Forest and the University of New Mexico.

The story goes something like this.

Prior to about 225 million years ago, this stretch of Arizona sat in a sunken basin, ringed by highlands. The whole place sat on the western edge of Pangea, which in turn lay astride the equator. Rivers flowed into the wet, warm tropical basin, leaving fine-grained deposits in lake bottoms and river deltas.

Floods sometimes stormed down those rivers, uprooting trees and carrying them to the river deltas and lakes, piling them up like jackstraws. Layers of mud covered those trees as the basin subsided, cutting off the oxygen before they could rot. This allowed them to fossilize in staggering numbers, creating the great draw for the Petrified Forest National Park.

Strange creatures wandered through the landscape – archosaurs whose descendants include birds and alligators. This included the armadillo reptiles of the Triassic, like the aetosaurs in bony, plated armor. It also included the fearsome rauisuchids, miniature versions of Tyrannosaurus Rex – which would not come along for another 150 million years.

They ruled the world, perfectly adapted to their times – sure they would last forever.

But the times they were a changing – and they were all doomed.

The restless, fickle crust that had gathered all the light continental rocks together into Pangea now shrugged and shifted. Fissures opened up, mountain ranges rose, volcanoes erupted, great basins sank and filled with sediment.

The meticulously reconstructed soils told the tale. Average rainfall dropped from 55 inches a year to 39 inches a year. The concentrations of CO2 in the atmosphere rose, starting at close to the modern level of 400 parts per million (ppm) and rising to maybe 800 ppm – although the calculations are approximate.

I marveled at the ingenuity of their measurements as I struggled through the long paper.

The researchers said this probably reflected the dramatic increase in volcanic activity as the continent broke up. But it could also have reflected the steady movement of the continents away from the equator, which changed ocean currents and continental temperatures.

In any case, temperatures rose, rainfall dwindled, lakes dried up, and the rivers changed their nature.

The baffled rulers of this shattered world faded away, leaving only bones turned to stone in the lurid layers of the Chinle.

I really can’t quite process it all, although it helps a little to finger the chunk of wood turned to agate with hollows glittering with crystal.

The world’s leaders recently concluded a climate conference, making bold statements and taking modest actions. We’re bracing for far less dramatic changes than the ones that swept away the rauisuchids, clearing the decks for Tyrannosaurus Rex. The toothy, 20-foot-long rauisuchids never saw it coming. We’ll have to see whether that fact will make a difference. I am comforted that we have among us people who can understand so much from this powdery soil. Surely, they’ll figure out something – starting with how to make us listen.

Not that I’ll know.

I’m already sitting here in the long shadow of my own personal extinction – with six grandkids and only a scattering of years left to ponder life’s great lesson.

A raven holds a rising thermal not quite overhead, studying me with its beady eyes. He is the heir of the dinosaurs, who in their turn inherited the world from the archosaurs. The dinosaurs had a good, long run – but they’re also gone. So now their offspring the raven makes his living as a scavenger, wondering whether I’ll either discard a granola bar or maybe keel over and offer up a more meaty meal. He does not know that I can trace my line back to the furtive, warm-blooded furry ones that hid from the passage of his mighty ancestors. But I know – so I keep an eye on him and marvel.

I ought to feel mournful, here in the graveyard of the Triassic.

And yet, I’ve always savored graveyards.

So peaceful, when all the striving is finally done.