Thoughts on Geology

Traveling in a vehicle can sometimes be boring. Some scenery is not very scenic. In places, the landscape is so the same for so long that you wonder if you’re moving or not. Maybe you’re just spinning your wheels and getting nowhere. That’s depressing scenery.
What makes scenic scenery is geology. The rise and fall of it. The wearing away of it. The colors of it. The heights and the depths of it. Varying geology makes the landscape interesting.
If you look at a map of western South Dakota, you find that the Black Hills are surrounded by an ocean of prairie. The hills were formed when a giant bubble of granite was heaved up and went through the earth’s surface. That eroded granitic bubble contains feldspar, quartz of many colors, mica, and other igneous and metamorphic rock. The soil around the bubble sparkles with the fine grains of mica, giving it a glittery sheen. Some of the trappers and Native Americans called the place the Shining Hills which accurately describes the center part of the hills.
Coming west, you travel through sagebrush and brown soils. South of Gillette, Wyoming, there are the Pumpkin Buttes, a trio of buttes out in the middle of nowhere. A couple of battles between the Cheyenne and Crow took place there. The son of one of the brothers who established Bent’s Fort in southeastern Colorado fought in those battles.
The Wind River valley lies between two mountain ranges and is appropriately named. The wind clears the valley of snow so game winters there. It’s not a place I’d want to live. It’s bitter cold there with the icy winds that blow. At the west edge of the Wind River valley, red rock cliffs appear out of nowhere, adding color to the landscape. The highway goes past these red cliffs and puts you into the foothills of the Absaroka Mountains. The pass over these mountains is not high or particularly steep and on the other side are the Teton Mountains.
The Tetons are an uplift, meaning that part of the earth’s crust was broken away and thrust up to form the mountains. From the east, they are massive and high and beautiful. From the west, they are not quite as high in relation to the surrounding countryside, but are still just as beautiful and rugged. The Snake River has eroded a beautiful canyon south of Jackson.
In eastern Idaho, shield volcanos spewed lava across miles of land, covering the ground with ragged, sharp rocks that are devoid of vegetation in places. The Craters of the Moon National Monument has trails through the lava fields, but stay on the paths. The folds, tunnels, and creases of the lava flows form a complex landscape where you could easily get lost.
Boise sits at the foot of the foothills leading in the mountains to the north. To the south are sagebrush steppes for many miles. The deep Snake River canyon cuts through the steppe and provides a view of the deep lava flows. The canyon and the landscape around the river were shaped by the Bonneville flood occurred at the end of the Ice Age. Global warming melted the glacial dam that held back a massive lake in Utah and in an event much much larger in scale than the failure of Teton Dam, the ice dam burst. The floodwaters carved the deep river canyon and scoured the landscape all the way to the Columbia River. The results of geological processes are a wonder to behold while imagining the forces of nature that made them.

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