I will be writing a couple posts about the recent field trip to the north - Minnesota/Wisconsin/Michigan. I can now cross Minnesota and Wisconsin off my list of states I hadn't been to yet. We spent the week looking at rifted sediments on the Lake Superior shoreline. We saw everything from the basalts when the rift began, to the shale, conglomerates, and sands deposited following the opening of the basin, to some igneous extrusive rhyolite, related to a volcanic event that changed the bed dips of the sands/conglomerates in the basin. The rift formed the basins for several of the Great Lakes, and they were subsequently carved out during advancement of the glaciers, and filled in with freshwater after retreat of the glaciers. It was a pretty nutty field trip, I haven't ever been on one that can compare in quirkiness. The saving grace was our SUV, filled with other young people.
Glacial striations on the basalt flow (that's what gives it the sheen/lines)
Hanging out with an anchor outside the hotel.
The early sunrise and the lighthouse
Fall trees
A waterfall over the conglomerate sequence.
A sharp contact between the conglomerate and a sandier unit. Most likely due to migration laterally and vertically of the alluvial fan/delta sequence
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