Minnesota’s Morton Outcrops SNA Contains Some Of The Oldest Rocks On Earth
Morton Outcrops SNA in Minnesota features some of the oldest rocks on Earth, dating back 3.6 billion years.
Minnesota did not officially become a state until May 11, 1858. But its history goes back much farther than that. Before European settlers arrived, Native American groups lived on these lands. Their ancestors, Paleo-Indian peoples, lived for millennia before them. And even before the first people arrived on this land, geologic processes shaped and changed what we now call Minnesota.
All of this to say that the land that makes up Minnesota is very old. So old, in fact, that some of the rocks now found in our state are among the oldest rocks on Earth. You can visit a little-known Minnesota nature area to see them for yourself. Read on below to learn more:
Morton Outcrops Scientific and Natural Area, or SNA, is a fascinating nature area in rural Renville County, Minnesota. It’s near Redwood Falls, about 110 miles west of Minneapolis.
At first glance, it may not be clear what makes Morton Outcrops SNA so special. It looks like a smattering of low rocks strewn across an otherwise unremarkable roadside field. There are several buildings, including a motel, nearby.
But if you learn a bit more about this SNA, you’ll understand why it’s a place of interest that is well worth visiting.
The rock, called Morton Quartz Monzonite Gneiss, is known for its pinkish color with bands of white, black, and gray.
It’s also known for its age. This gneiss is about 3.6 billion years old. That makes it the oldest bedrock in Minnesota - and among the oldest rocks in the entire world!
The bedrock was exposed by erosion from an ancient glacial river around 10,000 years ago. The river left deep potholes in the rock that you can still see today.
Many interesting wildlife species can be found among the low, flat rocks. Wildflowers and clovers are common. Rare fox snakes have also been spotted in the area.
All in all, this is a fascinating place that not many people know about. It’s home to interesting wildlife and some of the oldest rocks on Earth!
Have you ever visited Morton Outcrops SNA? Let us know what you thought in the comments! And if you're interested in visiting other interesting SNAs across Minnesota, check out our past articles about Butterwort Cliffs SNA and Falls Creek SNA.
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