Jeffers Petroglyphs, Minnesota
Steven Dutch, Professor Emeritus, Natural and Applied Sciences, Universityof Wisconsin - Green Bay
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A prominent escarpment on US 71 marks the edge of the Sioux Quartzite |
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The escarpment is drift mantled and shows no outcrop along the main highway. |
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There is a lower escarpment. The turnoff to the petroglyphs is just north of the trees. |
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View north from the base of the escarpment. |
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Looking north up the Sioux escarpment toward the petroglyph site. |
The Petroglyph Site
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The site is operated by the Minnesota Historical Society |
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The Visitor Center |
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The bare hilltop in the distance is a large expanse of Siouz Quartzite where the petroglyphs are carved. |
Rock Art
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The petroglyphs are subtle and their visibility depends on lighting. These near the start of the trail are some of the more deeply incised examples and include animals and handprints. |
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Roped off trails guide visitors through the site. |
Other Features
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Possible cleavage |
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Much of the outcrop is glacially polished. The petroglyphs are often carved on polished surfaces for better visibility. |
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Ripple Marks |
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Ripple Marks |
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Ripple marks and mud cracks |
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A beautiful snapshot in geologic time. A patch of mud cracks in the center of the picture entirely surrounded by ripple marks. Picture a small swell in an ancient tidal flat sticking just out of the water so it dessicates while the ripple marks nearby are preserved. |
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Cactus in Minnesota. |
Sioux Quartzite
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Outcrops of Sioux Quartzite near the petroglyph site. |
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View north down the Sioux Quartzite escarpment. |
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Created 7 April 2003, Last Update 06 June 2020