191 3] The Moraine Systems of Southwestern Ontario. 73 



Some of the details relating to the drainage associated with the ice 

 front at the time of the Paris and Gait moraines are given, because they 

 show with absolute clearness the impervious nature of the ice sheet, 

 that it was in effect a solid geological formation which served the pur- 

 pose of controlling the associated waters as effectively as would a for- 

 mation of solid rock. If the waters were running rivers it controlled 

 the rivers; if the waters were lake waters it was capable of serving as 

 a dam to hold them up to the level of the lowest point on their rim. 

 The same ice mass which formed the bank of the river along the escarp- 

 ment from Credit Forks to Acton spanned Lake Erie 100 miles farther 

 south and formed a solid dam which held up the lake waters in the basin 

 of Lake Erie to the level of an outlet in Michigan which carried them to 

 the Mississippi River and the Gulf of Mexico. 



The Moraines of the Ontario Ice Lobe. 



When the ice retreated from the Gait moraine it appears to have 

 withdrawn to an unusual distance, just as it did in Michigan before 

 the building of the Port Huron moraine. No certain evidence of terminal 

 morainic deposits have been found in the relatively wide interval be- 

 tween the Gait moraine at Simcoe and Waterford on the west and the 

 first of the slender moraines east of Grand River. 



I . The Crystal Beach Moraine. — This moraine starts at the shore of 

 Lake Erie just east of Crystal Beach and runs west through Sherks and 

 in broken form westward a mile or two from the shore to Lowbanks. 

 West of this it is lost, first in swamps and further on in extensive deposits 

 of sand. But it reappears northeast of Cayuga and is fairly distinct 

 northwestward to a morainic complex which it enters west of Ancaster. 

 This moraine and, indeed, the whole group on the Niagara peninsula 

 are of the faint, slender type. They are narrow and their relief is often 

 not over 10 to 15 feet, sometimes less. It is this weakness of develop- 

 ment that makes them so hard to follow and so easily obscured or lost 

 in sandy or swampy regions. 



This moraine finds its continuation in New York in the Alden 

 moraine which leaves the shore near West Seneca, south of Buffalo. 

 At Alden, 20 miles east of Buffalo, it overrides the Arkona beach ridges 

 in precisely the same way as the Port Huron moraine overrides them 

 on the "thumb" in Michigan and as the Wyoming moraine overrides 

 them in the Au Sable valley, south of Clinton, Ontario. This fact 

 leaves no room for doubt that the Alden-Crystal Beach moraine 

 of the Ontario ice lobe is the same as the Port Huron-Wyoming 

 moraine of the Huron ice lobe. Not only is this moraine east 



