CHAPTER XVI. 

 GLACIAL LAKE ARKONA. 



By Frank B. Taylor. 

 EARLY INVESTIGATIONS. 



The name "Lake Arkona" lias recently been applied to that stage of the lake waters in 

 the Huron-Erie-Ontario basin which immediately followed the last stage of Lake Maumee 

 and preceded Lake Whittlesey. Arkona is a village in the Province of Ontario about 50 miles 

 east of Sarnia, where Spencer 1 first observed and named the beaches. The name of the beach 

 was applied to tbe lake by the writer 2 in 1905. It is in some respects an unfortunate selection, 

 for the beaches are not strong nor typically developed nor even all present at Arkona, only two 

 of them being found there and three being strongly developed in the Black River valley in 

 Michigan, between Applegate and Avoca. No other name, however, has been suggested, and 

 though this designation was first applied with the distinct idea that it would be used only 

 temporarily, it has already appeared in print several times and will be used here pending a 

 better selection. 



The first observers of old shore lines in the lake region naturally gave more attention to 

 the stronger lines and so far as known did not mention the Arkona beaches. This is not sur- 

 prising, for these beaches are extremely faint in nearly all the region in which they occur and 

 are strong only in certain small areas. Spencer, 1 who seems to have been the first to record 

 their existence, observed them in Ontario and then crossed over into Michigan and identified 

 them on the slope west of Port Huron. He shows them in a profile of the beaches in the St. 

 Clair Valley. 



In the earlier studies of Gilbert and Leverett on the abandoned beaches in Ohio, Pennsyl- 

 vania, and western New York, a group of beaches within a vertical interval of 25 or 30 feet was 

 considered to be closely related, probably marking a gradual decline of one lake stage. Gilbert 3 . 

 called this series the "Crittenden" beaches, and Mr. Leverett 4 used the same name. Later, in 

 Ontario and Michigan, Spencer's names 5 "Arkona" and "Forest" were applied to the upper 

 and lower beaches of this group, respectively. In his studies of the surface geology of Monroe 

 and Wayne comities in Michigan, Sherzer 6 mapped two Arkona beaches hi considerable detail, 

 but reported the presence of only two. Mr. Leverett and the writer found three Arkona ridges 

 hi the Ann Arbor quadrangle. 7 



ARKONA BEACHES IN MICHIGAN. 



AKEAL DISTRIBUTION. 8 



Lake Arkona represents a time (see fig. 6, p. 370) when the ice had withdrawn some distance 

 north of the "thumb." After the beaches were made the ice readvanced, raising the level of 

 the lake waters east of the "thumb" without affecting those west of it, overriding and burying 

 part of the beach on the "thumb" and causing the remainder in the Huron-Erie basin to be 



1 Spencer, J. W., High-level shores in the region of the Great Lakes and their deformation: Am. Jour. Sei., 3d ser., vol. 12, 1891, p. 204. 



2 Taylor, F. B., Relation of Lake Whittlesey to the Arkona beaches: Seventh Ann. Eept. Michigan Acad. Sci., 1905, pp. 30-36. 



3 Geology of Ohio, vol. 1, 1873, p. 554. 



-< Am. Jour. Sci., 3d ser., vol. 50, 1895, pp. 10-20. 



5 Op. eit., p. 203. 



6 Monroe County: Ann. Rept. Michigan State Geol. Survey, 1900, pp. 136-140. 

 i Ann Arbor folio (No. 155), Geol. Atlas U. S., U. S. Geol. Survey, 1908, p. 7. 



8 As the ice barriers of Lake Arkona are not accurately known no map of this lake is given, but its barriers are supposed to have stood in 

 approximately the same position as those of Lake Warren. (See PI. XVII, p. 392.) 



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