Historic Bay City Tunnel
Behind this building lies the Bay City Tunnel of the Emma Mine. In 1873 the Emma received international attention when its silver-bearing vein faulted and British investors accused mine managers of fraud. British parliament discussed war, and President Grant’s administration scrambled to heal wounds. At the turn of the century the Bay City Tunnel was used to access the elusive ore vein. The Emma closed in 1918 having produced close to $4 million in silver ore. Today the tunnel leads to the source of the town of Alta’s culinary water supply.
Grove Karl Gilbert (1843-1918) is considered one of the greatest American geologists, having pioneered many theories in the earth sciences. In the late 1800s and early 1900s, Gilbert advanced concepts of mountain building, fault scarps, earthquake probabilities, and lake cycles that have withstood the test of time and are still used today. Furthermore, Gilbert applied science toward promoting public welfare by advocating the need for evaluation of risks and public disclosure of geologic hazards.
Utah was one of Gilbert’s favorite study areas where he formulated many of his theories. He spent much time at this particular location and was the first to establish that Little Cottonwood Canyon and Bells Canyon glaciers descended as far as the shoreline of ancient Lake Bonneville. Gilbert was also the first person to recognize the earthquake hazard posed by the Wasatch fault.
Silver ore was first discovered here in 1864. By 1873 there were 26 saloons in town. The town was called Alta because of its altitude. The population was upwards of 5000 people at times. The mines ran out and by 1895 the town was a ghost. A few of the mines were re-opened again in 1904 and worked until 1936. The old town sight of Alta is now a ski resort. Boiler Basin got its name because of a boiler that was left there after a train crash. Most people think that the train crash was the end of the train service in Alta but that is not true. A car was converted to run the cog railway line to transport people to Alta after the train crash.
The granite used in the construction of the Mormon Temple in Salt Lake City was quarried from a large field of huge boulders covering this area broken by nature’s forces from adjacent cliffs. The quarrying of these boulders was begun about 1862 by James C. Livingston, under supervision of John Sharp. The names of the faithful quarrymen who continued the work until the Temple was finished in 1893 are enclosed in the monument. Rough stones were hauled about twenty miles to the temple site suspended under great two wheel carts drawn by ox-teams, until the railroad was built in 1872.
The monument was refurbished and moved in 2004 to its current location by the Temple Quarry Chapter of the SUP.
See other historic markers in the series on this page for UPTLA/SUP Markers.
See Also: G.K. Gilbert Geologic View Park
Little Cottonwood Rocks
Geology and History of Little Cottonwood Canyon.
Little Cottonwood Bedrock
Three Bedrock units are visible on the north side of, and in Little Cottonwood Canyon :
- Little Willow Formation
The little willow formation is approximately 1.7 billion years old, making it the oldest rock in the Salt Lake City area. The highly metamorphosed rock consists primarily of intensely contorted quartz schist and gneiss intruded by igneous rocks that have been altered to amphibolite and chlorite schist.
Big Cottonwood Formation
One billion to 850 million years old, the Big Cottonwood Formation is a low-grade metamorphic rock that consists of reddish-brown quartzite and black to purple to green shale, argilite, and slate. Originally deposited along the shoreline of an ancient sea, ripple marks and mud cracks are still preserved in this rock.
The rock on the north canyon wall is easy to distinguish from the adjacent light gray “granite” father up the canyon.
Little Cottonwood Stock
This igneous rock is quartz monzonite, or more generally called granite. Between 32 and 31 million years ago, magma pushed up through the crust into overlying rock layers and then cooled and solidified before reaching the surface. Quartz monzonite is composed of plagioclase, quartz, orthoclase, biotite, and hornblende.
Popular for rock climbing, this light grey granite rock makes up most of the canyon walls.
A history of the rocks in this area :
In the 1860′s, a town named Granite was located at the mouth of Little Cottonwood Canyon by ore miners of Alta, Silverton and Tannersville. Its desertion began as the mines closed about 1882. The surrounding country had been settled by Latter-day Saints. Granite Ward organized July 1877, chose Solomon J. Despain, bishop. A rock ward house was used for worship and school until the completion in 1890 of the one-room building on this block.
Four miles east of Sandy City and south of Butler. In 1870 it was a good campsite for teamsters, quarrymen, and miners who were working in the Mormon church granite quarries and the mines in the vicinity. When transportation became more efficient during a time of reduced operations in this area, the camp was abandoned, only to be subsequently rejuvenated with modern, permanent residences. The town was named Granite because of its proximity to the granite quarries that provided the blocks for the Salt Lake Temple.