7/10/2023 0 Comments Devils tower wyoming roots![]() ![]() Nearly everyone agrees that Devils Tower was made from molten rock or magma, but that's where the certainties end and the fun begins. ![]() ![]() All of that movement meant volcanic activity was high, and molten rock below the crust surged toward the earth's surface. Scientists believe it was then that our beloved Rocky Mountains and Black Hills were born. Sometimes the shifts were explosive, as plates crashed into one another, pushing up mountain ranges. It was during this time that the continents made their way close to where they are today. It was a very busy time for the earth's tectonic plates. Roughly 50 to 60 million years ago, the earth was in the Tertiary Period. The water went through cycles of receding and returning for the next 59 million years, but something drastic was afoot. Because of that, geologists believe a shallow sea covered the area between 225 to 195 million years ago, during the Triassic Period. Wind and water help it form, making up much of the landscape around the tower. If you're fossil hunting, you're most likely picking through sedimentary rock. Sedimentary rock is created when minerals or organic material solidify. To this day, despite so much study and interest, experts are still baffled about much of its existence. It seems spectacularly out of place, resembling nothing close to the gentle rolling hills and prairies nearby.Įstablished as the nation's first national monument in 1906, Devils Tower's origins have long intrigued geologists, Native Americans, and casual visitors alike. Many of its visitors have marveled over this gargantuan rock specimen it's impossible to look at the surrounding landscape and not wonder how on earth the tower got there. Almost three times the height of the Statue of Liberty, Devils Tower is breathtaking for even the most seasoned travelers. Devils Tower owes its impressiveness to its resistance to erosion as compared with the surrounding sedimentary rocks, and to the contrast of the somber color of the igneous column to the brightly colored bands of sedimentary rocks.Tucked into a remote corner of northeastern Wyoming, Devils Tower juts dramatically up through the prairie, rising a staggering 867 feet from its base. The Tower is believed to have been formed by the intrusion of magma into the sedimentary rocks, and the shape of the igneous mass formed by the cooled magma is believed to have been essentially the same as the Tower today. Beyond this distance, they dip at 2 deg - 5 deg from the Tower. Within 2,000 to 3.000 feet of the Tower, the strata for the most part dip at 3 deg - 5 deg towards the Tower. The formations have been only slightly deformed by faulting and folding. The Sundance formation consists of the Stockade Beaver shale member, the Hulett sandstone member, the Lak member, and the Redwater shale member. These rocks, in aggregate about 400 feet thick, include, from oldest to youngest, the upper part of the Spearfish formation, of Triassic age, the Gypsum Spring formation, of Middle Jurassic age, and the Sundance formation, of Late Jurassic age. The hills in the vicinity and at the base of the Tower are composed of red, yellow, green, or gray sedimentary rocks that consist of sandstone, shale, or gypsum. Vertical joints divide the rock mass into polygonal columns that extend from just above the base to the top of the Tower. It is composed of a crystalline rock, classified as phonolite porphyry, that when fresh is gray but which weathers to green or brown. Devils Tower is a steep-sided mass of igneous rock that rises above the surrounding hills and the valley of the Belle Fourche River in Crook County, Wyo. ![]()
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