![]() ![]() They started running back towards their camp, but the bear was about to catch them. As the girls played, suddenly a bear began to chase them. The area was home to a great number of bears. One day, seven small girls were playing off in the distance from their tribe’s camp on the river. Here is my retelling of the popular legend: They may break again when impacting things or rolling, and today pieces of the Tower can be found over a quarter mile from the formation.There are several similar Native American legends about Devils Tower that have been passed down through the years, but the one I first read is from the Kiowa Tribe. Gravity is the primary force at work, pulling down loose rock. Once the rocks have broken off, or weathered, from the Tower, erosion does the work of moving the giant boulders. Rain, hail, and lightning all have gradual impacts to the Tower. The sun's heat results in thermal expansion, causing the rocks to shift or crack over time. ![]() These forces also contribute to the weathering and erosion process. ![]() The west and south faces of the Tower are the most exposed to sunlight and storm systems. Wind weathering is more visible in the softer sedimentary rocks below the Tower, but affects the boulders from the Tower by smoothing and rounding them over time. Plants contribute in a similar wedging process, which occurs as their roots grow down into cracks in the rock. Over time, this process of frost wedging can cause rock to split and break apart. If water seeps into these cracks and freezes, the expanding ice can force the rock apart. The Tower is full of natural cracks created by columnar jointing. Forces such as wind and water can contribute to both processes, but the mechanisms are different. Weathering is when rock breaks apart erosion is when rocks move. The processes of weathering and erosion are often confused. Predominantly around the west and south faces of the Tower, this field of giant rocks was created as pieces of the Tower weathered off and eroded down. Massive rocks, some large as a bus, form a 13-acre field. The boulder field provides a fun and challenging experience for visitors wanting to scramble over the giant rocks.Īt the base of the Tower, one will see the evidence of the changes it has undergone throughout its geologic history. White streaks are common towards the top of the red rock layer, evidence of the gypsum deposits. This led to substantial deposits of gypsum evaporating water left this white mineral behind, sometimes even crystallizing in small geometric patterns. The seas which deposited these sediments ebbed and returned throughout the Jurassic period, 195 to 136 million years ago. Deposits of sand, silt, and clay mixed with iron-rich minerals, giving the rock its conspicuous red color we see today. During this time, a vast area of present-day North America was covered in water. The formation dates to the Triassic period, 225 to 195 million years ago. Lakotas refer to this feature as the "race track," and the 500-mile circumference of rock is part of an oral history detailing a great race between Earth's creatures. The red and maroon cliffs along the east and southeast face of the Tower are only part of a sedimentary layer visible around the entire Black Hills region. Red Beds is so-named for the Spearfish Formation, comprised of the oldest visible rocks in the park. NPS / Chris Racay Hiking the Red Beds and Joyner Ridge Trails is the best way to see these other geologic formations. This view from the Red Beds Trail explains the name of our 2.8-mile circuit hike. The red cliffs seen in the park are part of a 500 mile ring of red rock that encircles the Black Hills region. ![]()
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