KEEP YOUR EYES ON THE ROAD: GARNETS AT BIG COTTONWOOD

 

Oh, keep your eyes on the road, your hands upon the wheel
Keep your eyes on the road, your hands upon the wheel
Yeah, we're going to the mountains
Gonna have a real
A good time ***

In Fall1967 as I, and my spouse, were moving to Salt Lake City and the University of Utah, I was dreaming about becoming a “mountain man,” or at least a geologist who works in the mountains. After all, that is a major reason why I decided on Salt Lake City---it was in the mountains. Or so I thought, maybe something like Durango, Colorado! My first shock was coming out of the Colorado mountains and hitting the high desert of the Piceance and Uinta Basins along U.S. 40 as it crossed the Utah and Colorado state line. Where were my Utah mountains? All we could see were scrub trees and sage. I wanted high peaks with an early snowfall. Did this part of the state ever receive snow, or even rain? My spouse might have suggested that we turn around and head---where? Not back to my home in Kansas, and besides, the only “money-earning” position I had was a NDEA Title IV Fellowship at the University. I am certain she thought, “where is my new husband, a geologist, taking me?” He promised me mountains with high peaks! Don’t worry, the map states we cross the 10,000+ feet Wasatch Mountains before we reach Salt Lake City.

We finally approached the small town of Park City (it was small at that time) and there it was—the eastern flank of the Wasatch Mountains, and they looked magnificent. The 1959 Pontiac pulling a small trailer started winding our way up to Parley’s Summit to ~7100 feet and then we then started down, really rolling down, “like there ain’t no hills like this in Kansas Toto” (and that was my second shock). Seems like we traversed the ~12 miles to the mouth of the canyon, losing ~3000 feet, in about 5 minutes (well maybe a tad longer) but we were really rolling. You could smell those old asbestos brake shoes a’burning. Although a flatlander, I did have the “brains” to gear down and keep my passenger from hiding on the floor but still thinking, “Oh my God, where is he taking me.”

My third shock came as we flew through the mouth of the canyon and discovered that Salt Like City was not exactly “in the mountains” but was spread over a very large valley, a really large city (250,000 at that time) considering that both of us grew up in towns with less than 400 inhabitants, including dogs. My previous schools in Hays, Kansas, and Vermilion, South Dakota, were not exactly in urban metropolises!

I'm goin' up the country, baby, don't you wanna go?
I'm goin' up the country, baby, don't you wanna go?
I'm goin' to someplace where I've never been before**

And then my fourth shock of the day sort of smacked me between the eyes---where do we go? The simple answer was just keep driving west. Finally, we arrived at the beginning of the Great Salt Lake Desert and the last cluster of SLC buildings. I pulled over and decided that if we kept on going west, we would hit Reno, Nevada, the next morning! Not a smart move for me and less so for my passenger who was thinking “where on God’s earth is he taking me.” So, I made a critical decision and decided to get a cheap hotel (easy to do in that part of town) and make decisions in the morning. We parted with a little of our scarce money and asked the motel manager if we could leave our trailer for the day as we hunted for an apartment. I am certain that he felt sorry for a couple of scared flatlander kids who seemed quite lost (and we were).

So, the next day, off we go trying to find the University and secure a “cheap” apartment close enough that I could walk to classes. And after less than two weeks of marriage, and numerous small setbacks, the romantic that I am told me to pick up my new bride and carry her across the threshold of our “new, cheap” apartment, and so I did 56 and a half years ago. And on all those future field trips where we traversed deserts and mountains and flatlands, and canoed rivers and lakes, and got lost (really just misplaced) I am certain that she thought, “where on God’s green earth is he taking me now?”

And it turned out that although the University was not “exactly” in the mountains, we could walk from my classrooms to the rock outcrops on the western flank. And that started our lifelong love affair with the Wasatch Mountains and Salt Lake City and the entire state. 

 

Wasatch Mountains looking east.  Photo by Brent Pace on Unsplash. Public Domain.

As we settled into a routine in our first home and at the University, we found time on Saturdays to start visiting the local sites: Great Salt Lake, the Oquirrh Mountains with the Bingham Copper Mine and the greater Tintic mining area, and the Wasatch Mountains. These nearby mountains are the major north-south range in Utah and follow the Wasatch Fault from about the Idaho border south to near Nephi where Mt. Nebo, the highest mountain in the Wasatch, anchors the southern point. At this location the mountains transition into the Wasatch Plateau where elevations on this rather flat area are consistently above 8000 feet. Physiographically the Wasatch Mountains are part of the Central Rocky Mountains and the Wasatch Fault marks the eastern boundary of the Great Basin (Basin and Range), a province that extends west to the Sierra Nevada Mountains (and therefore includes the Salt Lake Valley and the City).

Near Salt Lake City the benches (former beaches of Pleistocene Lake Bonneville) follow the mountains like a bathtub ring. I spent a substantial number of later years looking for, and excavating, Pleistocene mammals from “gravel pits” in these beach deposits---a story for another time. But in 1967 I was fascinated by looking up to the east edge of the city where Mt. Olympus (9000+ feet), Twin Peaks (11,330 feet), and Lone Peak (~11,000 feet) dominate the scenery---we followed the Yellow Brick Road to the high mountains Toto.

Besides the proximity of the Wasatch to the City, the inhabitants have access to a number of canyons with beautiful clear water streams roaring down to the valley. I soon learned that Mill Creek, although not of great length, had an accompanying road, was less crowded (although not at present), and supported a good fish population.

However, the two Cottonwood Canyons (Big and Little), both reached from roads in the Valley, attracted most of the attention then, and now.  In 1967 I was fascinated by the geology in both canyons and that interest remains today. The north canyon is Big Cottonwood where the first 6 miles are twisty and narrow (V shape) along a beautiful rock-strewn stream. Halfway up there is a dramatic change in scenery as suddenly the canyon widens (U shape) and the stream seems partially blocked by sediments, shrub willows, and rocks before lazily continuing to the settlement of Brighton. The mess of boulders and sediment is an end moraine of a mountain glacier that only made it partway down to Lake Bonneville from its cirque at Brighton.

The glacier in Big Cottonwood Canyon reached about half-way down and deposited a terminal moraine—with a nice U-shaped canyon extending upstream to Brighton.
 

In my opinion, 1967 Brighton was one of the most beautiful locations in Utah. It sits in a cirque that was the headquarters for the mountain glacier, had a small rustic log lodge, and was the oldest ski resort in Utah (1936). The glorious small Silver Lake in the cirque has a trail around it and attracts fish as well as moose. Of course, 2024 Brighton has changed! The rustic lodge is still there but the ski resort has greatly expanded in size. The building of new structures seems somewhat restricted so there is still the old timey feeling. Silver Lake is still occupied by moose and fish and now has an ADA-approved wooden boardwalk surrounding it. However, on the way down to the mouth of the Canyon and SLC, visitors notice an abundance of new homes scattered in the trees, businesses lining the highway and all of the buildings associated with a large ski resort, Solitude. In 1957 the “resort” opened with a couple of chairlifts repurposed from discarded mining equipment. By 1967 it was still a very small, family-type resort. By 1989 Utah’s first high speed quad lift had arrived, and by 1995, the resort condos had sprung up, skiable acres had expanded, and a major ski resort was present.

How can days and happenings and moments so good become so quickly ugly, and for no reason, for no real reason? Just—change. With nothing causing it. ― Philip K. Dick 

Mouth of Little Cottonwood Canyon showing the characteristic U-shape of the glacially scoured canyon. 

Little Cottonwood Canyon is the next major canyon to the south and is distinctly different from its next-door neighbor. The State Route 210 and Little Cottonwood Creek essentially run from the Canyon mouth in a fairly straight line for about eight miles to the summit and the community of Alta, one of the more famous old mining towns in Utah. The road and creek follow a beautiful U-shaped valley from top to bottom that was carved by a Pleistocene mountain glacier. Unlike the situation in Big Cottonwood, the glacier extended the entire length of the Canyon and further west into Lake Bonneville. Alta is one of the oldest and largest ski resorts in Utah and shares some terrain with its downstream resort neighbor, Snowbird. Near the entrance to the Canyon is Temple Quarry where giant blocks of quartz monzonite, granodiorite, and granite were quarried and transported to center Salt Lake City for use in the construction of the Temple of the Latter Day Saints (AKA Mormons). 

 

LDS Temple downtown Salt Lake City constructed of locally quarried "granite." Photo Public Domain.

During my stay at the University the Canyons provided some fantastic field trips, both formal and informal. Warm fall weather allowed for numerous excursions up the Canyons with picnic lunches in tow while winter snows turned the area into a winter wonderland. I was not a downhill skier for a couple of reasons: 1) the cost was too prohibitive for a student; and 2) my entire degree depended upon summer field work to support my research and a “broken leg” would put the kibosh on that activity.

Formally, the graduate classes allowed us to study the Canyons in great detail (at least for a student), and we always helped with the field trips associated with introductory geology classes. At that time in my early career my primary interest was in fossils and soft rock stratigraphy. The upper Canyons were covered in mine dumps and numerous tunnels (most off limits today) and holes, so I did collect mineral specimens; however, some were displaced in various personal moves, others were given to my more interested friends, and some remained with me and were used for teaching specimens during my career at Fort Hays. Only a very few remain with me today.

The Big and Little Cottonwood mining district was a large Pb-Ag producer active intermittently between 1867 and 1976. Although the Big Cottonwood and Little Cottonwood mining districts are sometimes reported separately, the division is completely arbitrary and the ore in both sub-districts is the result of a single, complex, magmatic-hydrothermal episode related to the intrusion of the Alta quartz monzonite porphyry stock (~35-33 Ma) along their common border. Approximately 60% of the past production has come from the Little Cottonwood subdistrict with the remainder from the Big Cottonwood subdistrict. Information from MinDat.com accessed January 2024.

On one of our informal trips a couple of my friends, my spouse, and  I were rummaging through some of the dumps in the upper section of Big Cottonwood Canyon. That excursion was over 56 years ago and I don’t have the slightest idea of which mine, and maybe I never knew that answer. We were more interested in hiking trails in the warm sunshine, sandwiches, chips, and a cold brew. One of the guys found some sort of a green to yellow mixture of very tiny crystals that appeared under a loupe to be “garnet” so we bagged some to examine at home. My big find was a tiny rock that had some sort of a mineral that looked like a graptolite (actually ludwigite). More on this mineral in a later story.

 

Andradite and calcite. Width FOV ~5 mm.

Andradite mounted on small nail heads ~2.5 mm.

A mixture of garnet width FOV ~13 mm. Yellow lines on bottom photomicrograph point to isolated small flakes of hematite.

Decades later I ran across these small finds while search a shoe box for “something else.” It turns out that I still do not know the exact collecting location except upper Big Cottonwood Canyon. My best guess is the Big Cottonwood Mine although there are many other mines and dumps in the region. The green-yellow “garnet” mineral has turned out to be andradite, a calcium iron silicate [Ca₃Fe³⁺₂(SiO₄)₃]. I know this little tidbit since MinDat.com stated, George Balogh did a SEM/EDS at Michigan Tech University with the results as A garnet containing calcium and with Fe > Al: andradite. Like all minerals commonly termed garnets, andradite is hard at ~6.5-7.0 and collectable specimens with some shade of green have an adamantine luster and commonly are faceted into jewelry gems. Demantoid andradite garnets (green and very small crystals) are perhaps the most sought-after and expensive gem “garnets.”

I am uncertain about the exact geological setting at the Big Cottonwood Mining District (66 valid species according to MinDat.com) but garnet in the District is associated with hydrothermal fluids, metamorphism, and the intrusion of the Alta stock. My specimens are quite small, usually a couple of millimeters +-

Those halcyon days at the University remain some of the best days of our life. We were free to roam in the mountains and deserts with picnic lunches and cold brews, the study of geology was fascinating, gasoline was cheap, we finally afforded a nice tent, picked up a used Coleman stove and lantern, and acquired an ugly dog. What more could two kids from the flatlands hope for? What can ever equal the memory of being young together? (Michael Stein).

**Goin-up-the-Country from Canned Heat.

*** Roadhouse Blues from the Doors except they were heading to a roadhouse rather than the mountains.

BITS OF TRIVIA

U.S. 40 is now I-80 through Parley’s Canyon and has the steepest grade of any interstate highway in the U.S---6 percent. And, you can still smell the burning brakes as those flatlanders “ride their brakes to the bottom.”

My family believes that I must hold some sort of a record for U-turns (not lost, just misplaced).

My spouse’s first camping trip was in a used sleeping bag (actually a double bag for two) underneath a spruce tree (no tent yet) on a field excursion.

Always helpful, she encouraged me to “find the portage” to the next lake as I led students through the Boundary Waters along the Canadian border with a funky compass not fond of iron ore, and helpfully pointed out high-on-the-trunk bear scratch marks at a few camp sites.

She became a fantastic cook with an iron skillet and tinfoil on a wood fire, often cooking for the entire field crew with two young children in tow.

But I survived, and we survived, and our two children are big fans of mountains, deserts, and the outdoors. The big changes have been moving from a spruce tree to a tent to a pop-up trailer, to a series of bumper-pull trailers, to a 38 foot 5th-wheel, to renting a VRBO condo. To me, nothing brings back memories of the past better than the smell of a campfire! Life is good.