336 PLEISTOCENE OF INDIANA AND MICHIGAN. 



TOPOGRAPHY OF THE BEACHES. 



ALTITUDE. 



The altitudes of the highest and middle Maumee beaches were originally determined by 

 Mr. Leverett 1 mainly by aneroid barometer checked by railroad levels. The Survey's topo- 

 graphic maps covering the course of the beaches between Tecumseh and Washington in 

 Michigan, including those of the Ann Arbor quadrangle, do not show any notable error in pre- 

 vious measurements. The maps of areas from Findlay to the western edge of the Delphos 

 quadrangle indicate that the altitude of the highest and middle Maumee beaches and of the 

 vicinity of the head of the outlet at Fort Wayne, Ind., is 5 or 6 feet higher than was previously 

 indicated. In the following resume of variations in altitude 2 the details are given somewhat 

 fully, because some of them will be referred to later. 



By the older measurements the altitude of the highest Maumee beach is 775 to 780 feet at 

 the head of the outlet in the vicinity of Fort Wayne and New Haven, Ind. Near the Ohio- 

 Michigan State line, 50 to 75 miles to the northeast, it is 20 to 25 feet higher. At West Unity 

 and Fayette, Ohio, the beach stands close to the railroad stations, at an altitude of 801 and 798 

 feet, respectively. At Fairfield, Mich., the altitude of the geodetic station is 799 feet. 



Mr. Leverett gives the altitude of the highest beach as 795 to 805 feet throughout the Ann 

 Arbor quadrangle. The strong beach is generally above 800 feet and at a few points rises to 810 

 or 812 feet. Two points that reach above the 820-foot contour are thought to involve some 

 error in contouring, for they seem too high for any phase of normal development even for a 

 storm beach. If the measurements are correct, such forms are likely to have had some special 

 mode of formation, such as the shoving of ice on shore by the wind or, more probably, some 

 occurrence associated with the formation of the deltas of Huron River in Lake Maumee. 



The highest beach continues at about the same altitude (800 to 810 feet) to a point 4 or 5 miles 

 north of Birmingham, where it begins to rise. It is 805 feet 2 miles west of Birmingham, but 

 at the north edge of the Rochester quadrangle, 1£ miles north of Washington, it is 820 feet. 

 From Clinton River northward about 25 miles to Imlay the beach rises nearly 40 feet or to an 

 altitude of 850 feet above sea level. The beach was traced by the writer to a fading termination, 

 at an altitude of a little more than 855 feet, in northwest sec. 21, Goodland Township, Lapeer 

 County, nearly 6 miles north of Imlay. 



On the south side of Lake Maumee the early measurements made the altitude of the highest 

 beach 775 to 785 feet from Fort Wayne to Cleveland. The new topographic maps show it to be 

 785 to 790 feet from Delphos to Findlay. Eastward from the Defiance moraine (see p. 279) the 

 middle beach of Lake Maumee marks the limits of the lake, so far as yet recognized. 



By early measurements the middle beach was found to have an altitude of 760 to 765 feet, 

 or 20 to 25 feet below the highest beach from the head of the outlet east of Fort Wayne to Bryan, 

 Wauseon, and Pettisville, Ohio. At Fairfield, Mich., it had an altitude of about 775 feet, and 

 in the Ann Arbor quadrangle of 780 to 785 feet, almost everywhere 20 to 25 feet below the 

 highest beach. It rises from 785 feet at Clinton River to 825 feet at Imlay. Toward Imlay it 

 is 25 to 30 feet below the highest beach. East of Almont it is 821 feet above sea level and 19 

 feet below the highest beach. Its bars on the moraines at Smith station and Berville are 820 

 feet above sea level. 



The middle beach is stated by Mr. Leverett 3 to have an altitude of about 765 feet between 

 Fort Wayne and Cleveland. But the middle beach is not well developed in the vicinity of the 

 outlet, and its identitj r and continuity among several weak ridges on the flat plain extending 

 eastward from New Haven, Ind., into Ohio have not been fully worked out. Some of the lower 

 of these ridges probably belong to the lowest beach, the place and relations of which in this 

 district remain to be determined. 



1 Mon. U. S. Geol. Survey, vol. 41, 1902, pp. 723-739. 



2 Mainly from Mon. 41, the Ann Arbor folio (No. 155), and the new Survey sheets in Ohio, 

 a Mon. U. S. Geol. Survey, vol. 41, 1902, p. 739. 



