Wednesday, May 23, 2012

Day 5 - Miscellany

On Tuesday, for my Geology of the Hudson Valley field course, we started the day with a 2-hour drive to Saratoga Springs, on the edge of the Adirondacks, where we examined a famous outcrop at Lester Park.  There, on the side of a country road, is a glacially-polished outcrop of Cambrian limestone loaded with exceptional stromatolite fossils.  During the Cambrian Period, around 500 million years ago, the Hudson Valley was a continental shelf environment some 30 degrees or so south of the equator.

From there we worked our way to Thacher State Park, west of Albany.  Thacher is famous for its section of early Devonian limestones exposed along the Helderberg Escarpment.  Unfortunately, it was raining and we didn't have enough time to hike Indian Ladder Trail but we did see examples of many common marine invertebrates, mostly in the rock walls of the park, including different species of brachiopods, bryozoa, crinoid stems, and trilobite fragments.

Finally, we finished up at the New York State Museum to examine their excellent minerals of New York and fossils exhibits.  We were able to see things like minerals from the Hudson Highlands (Day 1), dinosaur tracks from the Newark Basin (Day 2), reconstructions of the stromatolite fossils we viewed at Lester Park that day, and a fossil slab of starfish (Devonaster) and clams from near Saugerties (Wednesdays trip), among many other things.  The best part about the fossil exhibits is that they're laid out divided by geologic time with plate reconstructions showing where the Hudson Valley was during each of these Periods.

Once again, no pictures because even though the forecast was for a 40% chance of rain, it actually rained, sometimes hard, the entire day.

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