Great Sites: Medicine Wheel Geology

I recently had the privilege of visiting the Medicine Wheel atop Bighorn Mountain in Wyoming. It is the first time I have gotten to see the site although I have written several articles on it. The unusual formation of white stones originally attracted my attention as a possible archaeoastronomical site when astronomer John Eddy studied the formation and came to the conclusion that the spokes of the wheel could have been used to determine the summer solstice and other major appearances of significant astronomical objects including the stars Aldebaran, Rigel, and Sirius. It also impresses me as one of the very few permanent sites built by hunter-gatherer societies.

I have always been a little uncomfortable around edges, and to reach this site, we had to climb a narrow, winding road carved into the edge of a very steep cliff–the Medicine Mountain of the Bighorn Mountain Range. For most of the climb, we were chugging up a 10% incline so by the time we finally reached the parking lot of the Medicine Wheel, my heart was in my stomach and I was glad to be able to get out and stand on firm ground.

It was chilly at that altitude of 9,460 ft even though it was in early August, so we donned light jackets before heading up. The friendly ranger advised us that it is a one-and-one-half mile walk “up hill both ways”! We laughed but it turns out he is right. You go up and down and up again on the well maintained trail wide enough for a car.

The view is magnificent from that height where all around are forests and meadows and interesting rock formations. Where you have a bird’s eye view of the country below. We were quite winded after that last steep ascent but were excited to find we had it to ourselves except for the young ranger sitting on a cubical stone near the site. Accidently, we had timed it perfectly since we had met a stream of visitors on our way up and a large group arrived after we had been there awhile.

The fragile rock site is protected by a wire fence surrounding the circular wheel that is approximately 80 feet in diameter. I began by circling the wheel snapping pictures of the more prominent of the twenty-eight “spokes” especially where large rock cairns terminated the spoke (there are six circular rock cairns around the outer circle and one large cairn in the center). Then I sat down with the young ranger and we talked about it. I could tell that the young man was very passionate about the site and he offered many plausible explanations for its significance and its history. (I will write more about these different explanations in future articles)

One of the references he gave me was an article entitled “Sacred Geologies”. I have not been able to dig up the article yet, but in researching it I have run across some very interesting facts about the geology of the site. Here is a quote from the Montana Pioneer website:

“Medicine Mountain also has geological significance. There are 10 places on earth known as “nuclei of continents,” where relatively small patches of some of the oldest rocks on earth are found. These sections of ancient earth were first cooled on the surface of the planet’s crust 2 to 3 billion years ago, and overlaying younger rock has worn away. Also known as continental roots, these rocks were part of the super-continent Gondwanaland [Pangaea], which began to break apart some 300,000,000 years ago, and separated into the continents we know today between 65,000,000 to 1,000,000 years ago. The continents continue to drift today, but laid bare for the open eye to see are the layers of time exposed at Medicine Mountain, with the Medicine Wheel essentially floating on some of the oldest surface stone in existence on the planet. A nearly 360-degree view reveals a steady geological march downward from the summit of Medicine Mountain to the new earth and stone along the valley floors below, a look at the earth’s timeline that is unequaled by the other nine continental roots on the earth’s surface.”

These “nuclei” are also known as “cratons” and are exposed when they are pushed up during the process of tectonics or orogeny (mountain formation). The quote references the anomaly at Medicine Mountain where the earth’s layers of time are upside down. Where the oldest rock is on top and the younger layers of earth’s crust are in the valley. I found this diagram that explains how that is possible. As you can see, the older rock has been forced up and younger layers eroded away to reveal the ages exposed in reverse order.

I don’t think the original builders of the Medicine Wheel were aware of this geological phenomenon, but they must have sensed that this spot was very special.

#MedicineWheel #Indians #Wyoming #Geology