An unexpected mammoth

While visiting Wisconsin's Interstate Park over the weekend (happy 80th birthday, Smokey Bear!), I was surprised to come across another resident of the Cottage Grove area at the Ice Age Center:

According to the display, this mammoth tooth was discovered on Grey Cloud Island on July 9, 1987, by Arnold Sanford of Frederic, Wisconsin. This is the kind of thing that makes me wish we had an update to Stauffer "1945". (Even if I have to do it myself.) There must be plenty of other post-WWII finds scattered across Minnesota that are only known locally. When I was a little kid, my mother told me that part of a mammoth tooth had been found in Red Wing by a Boy Scout; I've never been able to find anything about it, but it certainly wouldn't surprise me!

Incidentally, the Ice Age Center also has other fossils and cast fossils of Ice Age mammals from the area. (Interstate Park is the western terminus of the Ice Age National Scenic Trail and one of the components of Ice Age National Scientific Reserve.) The most significant are bison bones and a cast skull from the park's bison bonebed, discovered in 1936 during CCC work. The bonebed is in my hopper of topics; until then, here are the specimens on display.

References

Stauffer, C. R. “1945” [at least 1948 based on dates in the article]. Some Pleistocene mammalian inhabitants of Minnesota. Minnesota Academy of Science Proceedings 13:20–43.

Life on Mill Street

We held another Cambrian hike at Interstate State Park on Saturday, and I thought it would be a good time to revisit some ground we covered in June of 2016. Specifically, at that time I glossed over the fossils of the Mill Street Conglomerate, but they're worth another look.

Cambrian island-hopping at Taylors Falls

Taylors Falls in the St. Croix Valley of eastern Minnesota presents an unusual geologic snapshot along a Cambrian coast. Within the south part of Interstate State Park, for an investment of a little more than a mile of walking round-trip, you can go from ancient basaltic islands, to the lithified rubble surrounding them, to the flanking sandy beach. Geologists love to try to paint verbal pictures of vanished settings, but rarely do the modern outcrops cooperate so nicely. Thank you to the park staff for suggesting an interpretative walk!

World of Stone

This is part of Devil's Parlor in the Minnesota side of Interstate Park, on the St. Croix River. I was at the park on Saturday for a park geology program, and following work I wandered through the Glacial Gardens section. Interstate Park, as its name suggests, has units in two states, in this case Minnesota and Wisconsin. The two parts are state parks, associated with but not part of St. Croix National Scenic Riverway (the Wisconsin side is also the western trailhead for the Ice Age National Scenic Trail, as well as one of the nine parts of the Ice Age National Scientific Reserve). Interstate Park is known for its glacial landforms, imprinted primarily on Precambrian bedrock.