Stones Neverending

One thing about Isle Royale: there are always plenty of rocks and stones to pick through and study. This photo is one of me, Captain Ben Kilpela, on a little nook of a stone beach -- I'm sitting in what is a semi-seacave -- on the north side of North Government Island at the north end of Tobin Harbor up near the very northern tip of Isle Royale, which is Blake Point. My son Logan and I were out this outer island for an afternoon, just exploring, when we came across this ordinary beach, just like hundreds of others in the national park. We spent some time just studying stones. What is it about stones and rocks that so interests people like us? I'll have to think more about that, but in thinking about it that day, I did realize that I spend a lot of my time at Isle Royale doing just what is shown in this photo, picking through and studying stones. As you might not realize, Isle Royale is a geological infant, almost what a geologist would call a newborn land formation. It came out from under the stupendously gigantic, miles-thick glacier that covered the Lake Superior region just 11,000 years ago. It was nothing but a big rock when the glacier melted and pulled back and alowed it to see the light of day, in the amazing ways glaciers do. But gradually the great Lake the glacier left behind in the Superior Basin begin to gnaw loose some cracked and loose sections of the rock -- and then began to tumble those loose chunks and pieces around -- and then began to toss the smoothed chunks and pieces up into nooks and crannies all around Isle Royale, where we find them now as stone beaches of all sorts of sizes and ages and formations. The stones I'm sitting on in the photo contained very few quartz-like pieces of silica and no semi-precious stones, no agates or greenstones, that I could discern. They were almost all pieces of basalt in an infinite number of shades of gray. I found even all those similar yet subtly different shades to be fascinating, as I always do. But why? Perhaps a little more thought will reveal an explanation. Rock-houding is one of the joys of Isle Royale.

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