Lost Lake – travel story from Polly
My second trip to
Lost Lake began on a misty morning in June.
A cool wet
forecast in the Highwood area sent me packing wool sweater, and a rain jacket.
But, I wasn’t as
finely prepared as my guide, Ron Long, EMT, volunteer fireman, and historian
par excellent, well known for his research of the rugged beauty of the Shonkin
Sag, Lost Lake, and the Square Butte area.
A trail of waterproof footwear and beverage coolers awaited my arrival
in Long’s driveway just off the highway straddling Highwood.
Long will trod
destinations within miles to share his love of his rural residence. His excursions are often accompanied by
others who share knowledge. We were
fortunate to be in the company of Chris Croff, a well traveled geologist, now
living in the Monarch area. Though Croff
had previously not explored Lost Lake, he was well aware of the area he
described as “glacially bribed,” and geomorphologically a “unique area.”
He is not
exaggerating.
It’s old
news. Lost Lake, about 70 miles northeast
of Great Falls, is the remnant of an ancient sea that roared during the
Pleistocene (ice age) thousands of years ago.
A glacier advanced and formed a series of glacial lakes along the
Missouri River and its tributaries. These lakes were confined by highlands to
the east. (For instance, glacial Lake
Great Falls formed west of the Highwood Mountains.) Eventually, however, the water level raised
high enough to spill over the natural barriers and carve out a new
channel. Today, this abandoned channel
is known as the Shonkin Sag, allegedly the Blackfeet word for the Highwood
Mountains, or an adulteration of one of the town’s early settlers, John Shonk.
The Shonkin Sag
happened when one of the continental glaciers melted scooting snow and rain
down. That dammed the Missouri River
which was hundreds of feet deep. The dam
became high enough that it flowed on the face of the glacier and formed this
area. The soil on one side of the valley
was dumped by the glacier which included rocks. On the other side there was a sea bed, the
bottom of which was shale. Eventually,
the decayed mountains eroded down to the present size to get rid of the volumes
of the mountains. Deep within the
earth, the molten magma melted, and changed the composition basically to a soup
that rose to the surfaces picking up minerals like potash, and feldspar .
Shoved under the mountain because of its thickness, the magma intruded up. It
expressed itself when it vented to the surface (volcano) and it left an unusual rock: Shonkinite.
“Shonkinite is relatively rare, found only in
a few places around the world,” Long told us as we turned onto the Shonkin
Road.
He pointed into
the distance to the grand and picturesque Square Butte and Round Butte where
vertical rocks encompass the land surface and form different linear
patterns. These are intrusive rocks, or
laccoliths of Shonkinite, that form a flat line feature with more vertical
extent.
Already, I found myself viewing hills and
valleys in a new way, encompassing new vocabulary. Part of this region’s secret is that people
look at the landscape and don’t understand what they are seeing.
“Once you have
the knowledge and pursue the rhetoric, then you have something you can walk
away with,” said Croff.
As we approached the Shonkin Sag several miles
on Shonkin road, the Sag ran east and went parallel to the road. Now it turns and starts off to the north. Here, you can see a valley where the river
was dammed and washed out an elongated depression between upland hills.
A rocky slope
revealed a gravel pit filled with Shonkinite: dark black or grey stones with
grey speckles. This is one pile of
rocks: millions of tons of gravel from a north flow of water that deposited it.
Long pointed to
explain that “when the glacier diverted the Missouri River, it didn’t always
run in one channel.” “It pushed the
river out further east of here into several other channels.”
From here, we approached
the channel where the river ran and formed Lost Lake. There are appearances along the way of volcanic
dikes, outcroppings of rocks that were formed by the river channel.
A sweeping green
landscape plunged us into a canyon along Shonkin Creek filled with bleached
sandstone and granite. Early summer
turns these lush hills to a vibrant green, dotted with yellow balsamroot. And,
the purple blossoms of Russian lilac sweetly invaded our geological
navigation. As a kid, Long fished along
this rock dike, bringing home a fine catch of trout!
Lost Lake was our
destination, but a series of other lakes lie along the Shonkin Sag.
“They are dead
lakes like the Dead Sea with an accumulation of salt,” explained Long.
“When they dry up
they leave a salt residue late in the summer.
The salt residue is evident throughout this area because when the
glaciers melted and formed shale, that was about three per-cent salt, the
source of the saline seeps that have caused so much trouble in this part of the
country. Shale is near impermeable. The water doesn’t sink into it, but
evaporates.”
Long motioned to
the slumping hills ahead of us, mostly made of shale with a thin layer of top
soil above that shale. The shale has bentonite in it, which when the soil gets
saturated, (especially in the spring) it slips, and makes the benches along the
hills.
“Even in my
lifetime I’ve seen it,” he said, stopping to show us the railroad track just
ahead which was covered with sliding earth from the slump.
After patiently following
an antelope down the dusty road, we turned into a small parking pullout.
A long walk
across a field, led us to a secret valley in the depths below. Here was Lost Lake, approximately one mile
long, surrounded by laccoliths and the dark outcroppings of Shonkinite
formations. From our vantage on a steep
promontory, the bluish green water was quiet and somewhat foreboding. The lake remains its old self, tied to the ancient
past with tales sunk in the deep still waters, hidden from most of mankind. The unspoiled prairie around the perimeter
gives way to numerous wildflowers lingering with blossoms of: lupine, wild
rose, prickly pear, and sandlily.
“Can you just see
the Missouri River dropping over these rocks,” pondered Long, as we stood
marveling at the experience and exploration of a long forgotten world.
This was why we
had made the day long journey to experience and savor such a geological wonder.
The adventure was worth a sustained pause to soak up as much of the strata as
we could. Now, we understood why the
guest book at the Four Sisters Ranch in Square Butte included a long roster of
famous geologists who had come to this area to do research and attend the 1989
International Geological Congress.
Among other things, our tour brought us
into the town of Square Butte where we stopped for a delightful lunch at the
Square Butte Country Club. We pulled up
to the lone parking meter, and stepped into the tiny bar and restaurant. Chef Amy was in the back baking desserts for
the Saturday night hoedown, but she came out to review the menu items which
included tasty burgers, homemade soup, Rocky Mountain oysters, and chicken
livers.
Before departing
Square Butte, we stopped to view the old jail house constructed in the late
nineteenth century of Shonkinite. The
square block stones and iron bar windows remain touchstones to the past and a
testament to the local construction one hundred years ago .
Focused on the idea of an unusual day escape,
there is much pleasure and novelty of encountering newfound geology, and
something old and ancient, like Lost Lake, and the historical surrounds.
Lost Lake is located on private
property. Occasionally tours are
available.
Call: Ron Long @ 406-733-5321.
.
