Time and Change at Chaco Canyon

[Listen to this post read by its author.]

"A generation goes, and a generation comes, but the earth remains forever. The sun rises and the sun goes down ... There is no remembrance of former things, nor will there be any remembrance of later things yet to happen among those who come after." (Ecclesiastes, 1:4-5, 11, RSV)

Chaco Culture National Historical Park, October 2019, photos by PB Laub

Trees and their shade are mostly absent here. In their place are stark cliffs of sandstone, slowly eroding in the ceaseless, arid wind. What draws people out here, nearly an hour of slow and bumpy road from the nearest sizable town, are the remains. Stone and masonry, as well as still abundant pot shards, stand in silent testament to what once was. Eight or nine hundred years ago, Chaco Canyon was a settlement or destination for the Ancestral Puebloan people, a site perhaps of trade or of worship. Then, abruptly, people disappeared; the site was abandoned.

What happened and why has been the subject of continuing speculation and debate. Some, like Jared Diamond, in his 2005 book Collapse, look for ecological or social causes of decline. Might the clear cutting the timber nearby been a factor, or over-reliance on food imported from great distances? Others, like Anna Sofaer, find, amidst the apparent disaster, evidence of advanced astronomical knowledge employed by the Puebloan people. So, might Chaco be a warning that feats of science and engineering offer little protection from societal collapse? The Roman Empire is long gone too, though their marvels of engineering, the aqueducts and the Coliseum, still stand.

I visited Chaco Culture National Historical Park last month, coming up from Albuquerque with others for a long day of hiking. I could write about a long climb up a narrow slot canyon beside Kin Kletso, about how glad I was not to know in advance about the steep ascent and, worse, the steep descent awaiting me. But no. More memorable was the enigmatic feel of the place, first experienced as an absence and, later, as a presence.

Fossils found in sandstone at Chaco Canyon, October 2019, photos by PB Laub

Fossils abound in the hard sandstone underfoot. You need not seek them out. Fossil impressions of shells and ripples suggest an ancient sea, one dated to the Cretaceous Period 85 to 75 million years ago. Then, a vast interior sea -- called the Western Interior Seaway  -- bisected the still-forming North American continent into distinct land masses. Once water washed this parched land. Walk further and notice what looks to be rusting rebar poking up through the rocks. "What the hell?", I wondered, baffled. What they are, a park ranger later told me, are three-dimensions casts of burrows made by crustaceans. Ophiomorpha Nodosa these casts are called. Iron in the cement filling the casts rusts, just as rebar rusts. And, being harder and more erosion-resistant than surrounding rock, these rebar-like casts are revealed as the softer surrounding rock disintegrates back into sand.
Even the hardest of rocks weather and erode. Sandstone crumbles back into the sand from which it was made, at some later time to be melted, compressed, or cemented into new rock. In geology, this is taught as the Rock Cycle. The cycle shows how rocks are forever being recycled and remade, the past they reveal erased and consumed.

Chaco is a somber place, a mute monument to the relentlessness of time. Seeing similar remains near Los Alamos several years ago, I wondered aloud, "and what happened to the people who lived here?" Someone overheard and surprised me, saying, "Oh, they're all around you. Their descendants are the people of New Mexico's pueblos." Evidently, continuity remains even as the connecting strands vanish.

Since that small epiphany, I've wondered how the world would feel if we let go and stopped resisting the passage of time. Ecclesiastes, the book of the Jewish canon quoted above, urges a return to God as answer to the ravages of time. Maybe, or maybe not. Rather than lamenting the brevity of life and the fragility of memory -- "there is no remembrance of former things", Ecclesiastes insists -- we might instead ride the wave of time as long as we live, celebrating the dynamic earth and its cycles, looking to the sky not for Heaven but for the heavens of stars and planets moving in a mathematical precision that we and our Native American brethren have figured out.

posted: 2019-11-23, last edited: 2019-11-24