Geology and Natural History of the BWCA and Quetico Park
Both the Boundary Waters Canoe Area and Quetico Park offer scenic vistas of sheer rock cliffs, dramatic waterfalls and some of the oldest exposed rock formations in the world.
As recent as 10 to 12 thousand years ago our area was covered by glaciers. The glaciers stripped away all traces of top soil and soft rock deposits and left behind a breath-taking barren rock land. Melting glaciers, underwater aquifers and precipitation filled the low land areas forming the over 600 lakes contained within both wilderness areas.
Travel along the US & Canadian border into the Knife Lake area. The Knife Lake area was at one time an under seas volcanic center which erupted and covered the under seas floor with pillow basalt. Knife Lake received its name from the Native Americans who once traveled the waterways. Knife Lake has a slate deposit which provided the knife and arrow tips of ancient cultures. After the glaciers subsided, the pillow basalt deposits were metamorphisized into was is fondly called Ely Greenstone - common to our area.
Knife Lake is just one of the many fascinating areas to visit. Plunging from heights of over a hundred feet into the cool lake depths, sheer rock cliffs of greenstone and granite form breath-taking natural artwork in the Agnes Lake (Canada), Ottertrack, and the Basswood River. Ancient fault lines also account for some of the straight, deep lakes with sheer rock cliffs running through The Man Chain, (located northeast of our base) and the Kahshahpiwi Lake area (located north-northwest).
Deposits of Jasper line the creek just off of Vera Lake. The Ensign Lake area shorelines show the well-weathered pink granite batholith that extends northward from the Virginia, Minnesota, area. The Vermilion Batholith, an intrusive rock formation, can be viewed on Kekekabic, Snowbank, LacLaCroix and Crooked Lakes. Evidence of volcanic "bombs" (chunks of rock blown out of a volcano) can be seen on Kekekabic Lake.
Iron ore, granite, greenstone, slate, graywacky and pure quartz deposits are just a few of the many rocks and minerals native to our area. No matter what area you choose to visit, fascinating geological formations will be found. Whether a weekend or educated geologist, the spectacular sights and formations are sure to please.
Geological finds are not the only "gems" present in our vast wilderness area. After spending a long day scaling cliffs and studying shorelines, a quiet evening around the campfire will be in order. With cup of coffee in hand and the campfire gently crackling, the sunsets and the evening stars begin to shine. Over the northern horizon a misty green glow appears and hovers quietly. As the night progresses, the misty green begins to gently sway taking on forms of rays, bands and arcs - sometimes intermixed with reds and blues. The Aurora Borealis, or northern lights, has begun its evening dance.
Quetico Park is characterized by its haphazard drainage pattern. Ultimately, all waters in Quetico drain into the Arctic Ocean westward through Rainy Lake to the Lake of the Woods, Lake Winnipeg and into Hudson Bay. Several of the Park's watersheds lie outside the Park boundaries so activities occurring outside the Park can have a direct impact upon it. The most common soil in Quetico Park is ground moraine composed of sand mixed with rocks and gravel, forming a discontinuous layer usually less than one meter deep. The soil is very base and low in nutrients. As Quetico Park lies in a transition zone between the boreal forests to the north, the mixed forests to the south, and the great plains to the west and southwest it contains diverse flora.
The lakes of the BWCA were carved from Precambrian bedrock of the Canadian Shield by advances of ice sheets during a succession of ice ages during the past two million years. Many varieties of this ancient bedrock are exposed, including granite, basalt, greenstone, gneiss, as well as metamorphic rocks derived from Precambrian volcanic and sedimentary rocks. Greenstone located near Ely, Minnesota is up to 2.7 billion years old. The size and shape of most lakes in the BWCA are dictated by the bedrock, due to the ability of glacial ice to erode softer and weaker rocks more easily, creating depressions later filled with water
Life times have been spent trying to explain the eerie and mysterious appearance of the "lights". Early cultures feared the appearance of northern lights and would run screaming and yelling in an effort to chase away the evil. Sleds pulled by reindeer were often adorned with bells to keep the dangers of the lights at bay. Other cultures believed that the lights were the spirits of those passed on. Nunamuit Eskimos used the lights as guides to good hunting. And still others believed that the lights held the power to cure and restore health.
Through the centuries of myth, humans have struggled to explain just why the lights exist. Today's explanation directs our attention to the solar winds, magnetic fields, magnetosphere, auroral ovals and Birkeland's currents. In simplest terms, solar winds carrying charged molecules pass through the Earth's magnetic fields causing the electrons to be caught up in Birkeland's currents around the polar regions. As Birkeland's currents plummet to the earth, collisions begin to occur between the currents and oxygen molecules. As the oxygen molecule becomes "excited" from the collision with the current, it gives off a short burst of greenish light. It requires thousands of these collisions to form the visible northern lights. The varying colors of the northern lights (blues, greens, pinks and reds) are the result of variations on element (oxygen or nitrogen) collisions, magnetic storms and sub storms.
Although to many the northern lights remain a mystery, its beauty and legend are certainly enjoyed by all. To best view the northern lights, plan your wilderness canoe trip around or close to a new moon. Enjoy and explore the natural wonders of the north woods.