Here, the Upper Triassic Luning Formation—specifically the Early Norian Kerri Zone—reveals itself in a series of beautifully exposed beds, each one a page in a story written some 220 million years ago.
This outcrop is a reference point, a kind of stratigraphic Rosetta Stone for understanding the Carnian–Norian boundary (CNB) on this side of the ancient world.
Back in 1959, the formidable J.W. Silberling carefully documented the rich ammonoid faunas preserved here, establishing the Schucherti and Macrolobatus zones of the latest Carnian.
These are then overlain—rather obligingly—by the earliest Norian faunas of the Kerri Zone. A neat geological handshake across deep time… and then, curiously, silence. For half a century, no one returned to press the story further.
Enter a trio of sharp-eyed Vancouverites—Jim Haggart, Mike Orchard, and Paul Smith—who, in 2010, decided it was high time to dust off this remarkable section and ask a few new questions. Armed with rock hammers, hand lenses, and a healthy obsession with the microscopic and the coiled, they conducted a meticulous bed-by-bed sampling of ammonoids and conodonts through the canyon walls.
On the eastern flank, the Macrolobatus Zone struts its stuff—ammonoids of the Tropites group and Anatropites making regular appearances. Meanwhile, the conodonts—those tiny, tooth-like fossils that palaeontologists adore—are dominated by ornate metapolygnathids.
These were once all lumped together under Metapolygnathus primitius, a species famous for straddling the CNB like a geological fence-sitter. Here, they show closer affinities to M. mersinensis, with a cameo from forms akin to Epigondolella orchardi and even a new Orchardella species joining the party.
And here’s where it gets rather delightful—this assemblage ties beautifully back to the latest Carnian faunas of British Columbia. A transcontinental whisper between Nevada’s desert stones and Canada’s coastal mountains.
Climb a little higher in the section and—ah!—the plot thickens. The ammonoid cast shifts dramatically, now dominated by Tropithisbites. Not far above, just shy of the first true Norian ammonoids—Guembelites jandianus and Stikinoceras—two brand-new conodont species appear.
These same forms are known from British Columbia, right at the favoured CNB. It’s correlation at its finest—like matching fingerprints across an ancient ocean basin.
Over on the western side of the canyon, the Kerri Zone is displayed in full flourish. Ammonoids abound—Guembelites, Stikinoceras, and friends—stacked through multiple fossiliferous layers. The conodonts echo those of the eastern section, reinforcing the story.
Interestingly, while these faunas align well with Silberling’s original descriptions, they show subtle differences from coeval assemblages in the Tethys and even from those in Canada. Notably absent is Gonionotites, a genus common elsewhere but conspicuously missing in Nevada’s lineup. Here, the Tropitidae reign supreme, while the Juvavitidae sit this one out.
And then—because science is always best when paired with a good pair of boots—I had the absolute pleasure of walking these very beds in October 2019 with members of the Vancouver Paleontological Society and the Vancouver Island Paleontological Society. The same spirited crew I’ve roamed the Canadian Rockies with since the early 2000s, when many of these correlations were first being teased into focus.
There’s something quietly magical about tracing those connections in person—linking Nevada’s desert ridges to British Columbia’s coastal outcrops through ammonites no bigger than your palm and conodonts you can barely see without a microscope.
