Monday, November 1, 2010

Dunes, New Road, and Stromatolites

I am trying my best to get back into the hiking mode. Before I left on the down state trip, I did get in a dunes hike. We have had several storms lately, some of which leave their erosion evidence down the banks of the Grand Sable Dunes. In the picture below, you can see the erosion trench that is 4-6 feet deep and deposits sediment at the bottom of the dune.

Here is a shot of one of the trees in the dunes that was still holding onto its colorful leaves.

The mushrooms were more prolific in August than in September and October, which is unusual. Here is a cool family of fungi clinging to the side of a tree near the dunes.

A couple of Sundays ago I gave my agate talk at the Ishpeming Gem and Mineral Club meeting. It gave me the perfect opportunity to drive the new road between Grand Marais and Munising. Yes -- the road is finally completed and open! Although not everyone agrees with the road, anyone who drives it will admit that they did a wonderful job. As compared to the old road that was not more than a ditch from decades of grading, the new road elevates you so you can see the forest as you drive through. The new road also maintains most of the curves which seem to give you glorious views of the forest communities as you drive through the National Lakeshore

I measured the distances from downtown Grand Marais. The new bridge over the Hurricane River is 11.8 miles.

As you continue the drive west, there is a new parking lot and bathroom facility at Sullivan's Landing, located 13 miles from Grand Marais. For those of you who have not heard the story, there was a schooner that hit the rocks at Au Sable Point back in the 1800s. Captain Sullivan told the men to abandon ship. They refused to jump into the waves of Lake Superior. The Captain proceeded to throw the cargo over board. Since their cargo were whiskey barrels that floated, the men did abandon ship to float on the barrels to shore. All hands and all barrels were saved.

As you continue driving, the access road to 12 Mile Beach is 15 miles from Grand Marais while Kingston Lake is 19 miles, the junction with Adam's Trail is 23.3 miles, Melstrand and the access road to Chapel is 35.3 miles, the Bear Trap is 40 miles, the access road to Miner's Castle is 44 miles, and downtown Munising is 49.3 miles.

I stopped at the MDOT Rest Area located a few miles from Marquette. I grabbed a copy of a flyer they had about the geological wonderland of Marquette. Across the street from the rest area is a cliff with various rock formations including 2.6 billion year old schist, quartzite, slate, dolomite, and quartzite as well as remains from the algal stromatolites (cyanobacteria). When the rock across the highway was deposited, the earth's atmosphere was oxygen-poor and carbon dioxide-rich. One of earth's earliest forms of life, cyanobacteria, had the capability of consuming carbon dioxide and generating oxygen. If it were not for stromatolites changing the atmosphere, life as we know it on Earth today would not be possible.

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