Geography of Chequamegon Bay-:1-: The geographic· focus the meltwater formed The Ashland plain . and the center of settle­ a lake (Lake Duluth) rises gradually from the ment and economic activ­ between the face of the wetlands and bluffs at its ity in the Chequamegon glacier and highlands to coastal margin until it Bay region is the bay . the south. abuts the highland that itself. Oriented along a The retreating glacier surrounds it from the northeast-southwest axis, also deposited on top of northeast to the south­ it is about 12 miles long the ancient sandstone west. to the sand spit that lies huge quantities of mixed This highland area across its mouth and is sand, clay, and rocks consists of two ranges, about 10 mileS wide at of all sizes that it had the copper range and far­ that point. scooped up as it ad­ ther south, the Penokee This spit extends vanced. The highland of range. The copper range, northwestward from the Bayfield Peninsula a continuation of the cop­ the southern lowland to is a ridge of such gla­ per bearing formations of within about four miles cially deposited materials the Keweenaw peninsula, of the Bayfield Peninsula Lars L) heaped up on the under­ forms the frontal escarp­ and consists of Chequa­ 2- lying sandstone between ment of the highland. megon Point and Long Larson b) t/ 1-z-- the two glacial lobes to Near the mouth of the Island, the two separated • has been a guest colum­ 600 or more feet above Montreal River the cop­ by a narrow water gap. nist for The County Journal lake level. per range rises rapidly The spit and island for many years. The terrain at the to an altitude of 500 feet serve as a natural break­ summit (the ''barrens") is above the lake, trends water, protecting the remnants of the great hummocky with numer­ southwest to the vicin­ bay against the fury of faults thus created. ous circular depressions ity of the Brunsweiler storms on the main lake. This rift valley was or "potholes" characteris­ River, and then continues The water is shallower in subsequently filled with tic of kettle moraine. The just southwest toward that part of the bay that sedimentary rocks that' predominant type of soil Lake Namakagon. While lies to the southeast of · were then removed by here is sand of various eastern portions may a line from the outer tip glacial erosion during the grades of coarseness, ex­ attain altitudes of 700 to of Chequamegon Point Pleistocene period, giving cept for patches of loamy 800 feet above lake level, southwest to the head of the basin essentially its sand or where organic for most of its length it the bay, and at the head present configuration. materials have been laid ranges from 550 to 650 of the bay itself, than on The major features of over or mixed in with the feet above the lake. the northwest side, where the Chequamegon Bay sand. Farther south the it ranges in depth up to region- the bay itself, Lake Duluth laid down Penokee range, a topo­ 70 feet. the Bayfield Peninsula, a terrace of clay around graphical continuation The Chequamegon Bay ·Apostle Islands, and the the drift material of the of the Gogebic Range to region lies in the Lake Ashland plain- were highland and a thick the east in Michigan, Superior lowland, one of probably formed by layer on the Ashland trends generally north­ five geographic regions glacial modification of plain and the Apostle east-southwest, rising into which Wisconsin is pre-existing drainage Islands. The numerous to heights of from 900 to divided. Although the bay patterns in the ancient rivers and creeks that 1,200 feet above lake lev­ region is part of the basin sandstone during the flow into the lake down el. It is broadest near the of western Lake Superior, last glacial age, 10 to 50 the flanks of the highland Montreal River, becoming its geologic history is dif­ thousand years ago. have swept out broad val­ narrower to the west and ferent. This glacier, the leys in the soft clay and declining rapidly to the The western end of the Wisconsin, advanced cut narrow gorges into local terrain elevation lake basin (not includ­ into Wisconsin from the sandstone. near Mineral Lake. ing the bay area) was the northeast in great The Apostle Islands The copper and Peno­ formed when a block of tongues or lobes- the are an extension of the kee ranges are geological­ crust dropped down to Superior lobe to the north Bayfield Peninsula, the ly distinct, but topograph­ form a rift valley called and the Chippewa lobe to channels separating them ically they merge into a a graben. The Duluth the south. from each ofhet and from broad band of highland of escarpment to the north As the glacier retreat­ the peninsula having which the latter range is and the highland south of ed, that is as its front been created by water the most prominent. Superior are the eroded gradually melted away, and glacial erosion. .
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