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Discovered in 1989, the Acasta Gneiss is an outcrop of metamorphic rock dating from the earliest part of the Precambrian Era. It falls within the Hadean Period, which started with the formation of the ...

After 40 minutes or so of skirting around enormous boulders, hurling myself up steep dirt trails, and staring slack-jawed at gigantic slabs of granite, I finally track down the echoing voices of two ...

MinnPost’s reporters work hard to bring you news about what’s happening in MN. Your tax-deductible donation today will show your support of our journalists and keep our stories paywall-free. Morton ...

Oldest North Cascades bedrock, a 400-million-year-old tale from European origins. The oldest bedrock in all of the North Cascades sits high in the mountains near the Canadian border. Its origin story ...

What we know today as Sabino Canyon was the site of a whole lot of scrunching 25 million years ago. In a geologic nutshell: Two ancient types of rock - 1.4-billion-year-old Oracle granite and ...

The people at the Smithsonian Institution National Museum of Natural History were nice enough to give a couple members of the Chemistry in Pictures team a behind-the-scenes look at their mineral ...

In a recent study, geologists say Michigan is home to the oldest known rock in the nation. Watersmeet gneiss is found in Michigan's Upper Peninsula. Minnesota's Morton gneiss previously held the title ...

I’m sure you’ve noticed certain very localized areas -- sometimes not larger than a basketball court or maybe covering part of a mountainside -- where the ground is covered with a single species like ...

Torkil S. Røhr, Bernard Bingen, Peter Robinson and Steven M. Reddy AbstractThe Western Gneiss Region, western Norway, consists of Paleoproterozoic crust of Baltica ancestry (Baltican Basement), partly ...