North Shore Lake Superior, Minnesota

Steven Dutch, Professor Emeritus, Natural and Applied Sciences, Universityof Wisconsin - Green Bay

Z: Precambrian Z sandstones
Yi: Precambrian Y intrusive rocks (Duluth Gabbro)
Ys: Precambrian Y clastic sedimentary rocks
Yv: Precambrian Y volcanic rocks (mainly basalt)
X: Precambrian X metasedimentary rocks
W: Undivided Precambrian W rocks (Archean gneiss and other metamorphic rocks)
Wg: Precambrian W granite
Wv: Precambrian W metavolcanic rocks (mainly greenstone)

Superior and Duluth

Superior, Wisconsin, looking toward the bridge to Minnesota. The distant hills are igneous rocks of the Midcontinent Rift System.
Looking south up the St. Louis River.
Left and below: views from the top of the bluffs. Views start looking south along the bluffs and rotate north.
Left and above: Minnesota Point is reputed to be the longest freshwater baymouth bar in the world.

Below: Looking north along the bluffs.

Duluth to Grand Marais

Left and below: views along the shore northeast of Duluth
Silver Cliff Tunnel on Highway 61. Although maps always show this as a scenic route, much of it is pretty disappointing. The lake is rarely visible, and Split Rock Lighthouse, shown on every brochure of the region, is visible from the highway for only a split second, although a view has recently been cleared from a nearby overlook. But there are some nice waterfalls.
Left and below: Gooseberry Falls
In an all too rare occurrence, the Minnesota highway department cut brush from an overlook, opening a view of Split Rock Lighthouse.
Left and above: views on the shore near Taconite Harbor

Below: Iron ore dock at Taconite Harbor.

Left and below: Temperance River falls and gorge.
Left: Temperance River Gorge

Below: Shoreline views

Cascade Falls.
It's only northeast of Grand Marais and especially near Grand Portage that the shoreline scenery gets really interesting.

Grand Portage

This was one of the notoriously arduous portages on the French fur route. It cut off a long stretch of rapid water but was 8-1/2 miles long. You didn't portage something like that any more than you had to, and a portage of a fur party took several trips, so the fur traders carried loads at the outer limits of endurance. Between extreme physical demands, accidents, poor nutrition, and exposure, voyageurs rarely lived to a ripe old age.

The Grand Portage, or Great Carrying Place, was a key 18th century link between the Pigeon River and Lake Superior, making it a vital connection between Montreal and the rich fur-bearing lands far to the northwest. Traveled for centuries before by Native peoples, the 8.5 mile portage bypassed the unnavigable rapids and waterfalls on the lower 21 miles of the Pigeon River. Beginning about 1731, thousands of tons of furs and trade goods were carried across the Grand Portage on the backs of voyageurs. Each summer a great Rendezvous was held on these grounds near Lake Superior. Most of the trade here was over by 1803, but use of the portage is still covered by an 1842 treaty.
Reconstruction of the trading post.
Left and below: views from the shore.

These photos, looking inland from an overlook just north of the trading post, give an idea what the portage terrain was like.
Left and below: an overlook just north of the trading post offers a spectacular view of Lake Superior with Isle Royale in the distance.
The geology north of Grand Portage consists of early Proterozoic rocks intruded by Keweenawan sills. The sills form steep bluffs and flat-topped hills that are, for all practical purposes, mesas.
Looking north not far from the Canadian border.

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Created 24 May 2006, Last Update 08 June 2020