By on August 10, 2016

Embracing the geology and humanity found on a favorite Jackson Hole hike.

Andrea Overly (a.k.a. “Ms. O”) points out some gneiss stripes on an adventure exploring Jackson’s geological history. (Photo: Andrew Munz)

Andrea Overly (a.k.a. “Ms. O”) points out some gneiss stripes on an adventure exploring Jackson’s geological history. (Photo: Andrew Munz)

JACKSON HOLE, WY – I’ve never known a bigger dork than Jackson Hole High School science teacher Andrea Overly. Although we haven’t been friends for decades, our two personalities mesh like huckleberries and milkshakes. Both of us were raised in Jackson Hole, but were born on opposite sides of the country. We also have a few things in common that appear trivial—we’re Andy and Andi; we were born just a day (and some years) apart—but have seemingly strengthened our bonds of friendship. Other friends have admonished us: we’re not allowed to huddle in a corner at parties quoting YouTube videos and making weird sounds; we actually have to talk to other people.

Since I’ve always had a fascination with the long lost history of the Hole, I was eager to yank Andi on a hiking adventure, recording our chats along the way. Since she teaches ninth grade earth sciences, we picked a hike up Death Canyon, an area ripe with geological mystery, and a place that has had a profound impact on both our lives while growing up. There was no knowing how many times either of us had leaped from the massive jumping rock at Phelps Lake, how many birthday parties or family excursions had led us up that familiar forested trail.

Along the way, I asked Andi to tell me how our home valley was formed.

“A long, long time ago…” she began.

“…in a Hole not so far away…” I continued.

“…in a Hole that didn’t even exist yet, there were two tectonic plates that crashed into each other. And when two tectonic plates love each other very much…”


“They make metamorphic rock!” she squealed in delight.

I had clearly forgotten a lot of the curriculum from (sigh) 15 years ago.

Andi continued the lesson as we walked, telling me about how the Teton Range rose from the ground as the valley sunk deeper into its shadow. Using terminology that I hadn’t heard since I was 14, Andi went into detail about foliated metamorphic rock, particularly her favorite type of rock: gneiss (pronounced “nice”).


“Dude, it’s so nice…” Andi agreed.

Andi bent down to pick up a grey rock with white striations, saying it was one of the most common rocks to be found on the valley floor. The stripes are created when heat and pressure are administered on parallel sides. We spent most of the hike keeping our eyes peeled for more gneiss.

“The cool thing about the canyon and Phelps Lake is that it was all formed by glacier movement, which is why you’ll find granite down here, when normally in our valley, granite’s found up high,” she explained.

The Phelps Lake jumping rock is an enormous slab of granite that was carried down with the glacier, the lake itself being the remnants from that glacier. Beneath the lake you’re sure to find even more granite, which is a type of igneous rock that was once melted down to magma, and then cooled, crystalizing the minerals trapped within.

We passed a multitude of tourists, smiling families, young and fit couples, older folks with walking sticks and bells. And as they took in the present-day sights, Andi and I were in deep discussion about the valley’s ancient history, which was visible in every direction, but required a trained eye.

Standing at the overlook, smiling and catching our breath as we stared out at Phelps Lake in the alpine breeze, a kind family from Philadelphia asked if we wanted them to take our picture.

“Of course!” we said in unison.

I know that many locals and “locals” (side-eye…) are somehow allergic to popular trials with tourists. But when you remember how old this area is, how much history is involved and how many shoes have walked the same trails over and over again, it’s hard to feel any sort of selfishness or entitlement.

Exhausted with our grueling, single mile-long round trip, we decided we deserved a drink. Sitting on the Dornan’s deck, sipping on our ramshackle bartender’s margaritas, we stared up at the massive igneous rocks that we called home.

We sat in the smokey sunshine with smiles on our faces, two dorks, discussing life and geology, making weird noises. “Mlem,” Andi said, tonguing her straw. PJH

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