474 A. W. G. WILSON SHORELINE STUDIES ON ONTARIO AND ERIE 



is a nearly continuous strip of wide beach, the greater part of which con- 

 sists of sand with some grayel. Tliere is reason to believe that the initial 

 topographjr of the district was that of a series of coniiuent river valleys 

 divergent toward the northeast. The glacial modifications were very 

 slight, and consisted largely in the addition of a surface blanket of loose 

 waste. In the early history of the present lake partial submergence of 

 these valleys produced a number of deep ba3's with rocky points between. 

 At the present time all of these bays are cut off from the main lake by 

 the series of bay-bars under discussion. 



From its position with reference to the open lake, the coast is exposed 

 to the direct action of winds and waves, which have the full sweep of the 

 lake. Master storms would advance on the beach front almost normal to 

 its face. The character of the material of which the bars are built shows 

 that it did not come from the north. Material brought by shore trans- 

 portation from the west would nearly all tend to be deposited in the 

 southeast corner of the lake, southwest of Port Ontario, by reason of the 

 form of the shore at this localitj^. Very little, if an}', of it would move 

 northward along the beach. An investigation of the l^eaches themselves 

 shows numerous minor irregularities, with no systematic development of 

 offsets or overlaj^s, conspicuous features of several barrier beaches else- 

 where on the lakeshore where longshore transportation is undoubtedly the 

 dominant factor in. their construction. 



In the initial stages the interbay headlands undoubtedly supplied a 

 small amount of material to construct wing-bars on each side of each 

 headland. The present bars, however, contain an enormous amount of 

 material, far more than could have been su2:iplied by the preexisting head- 

 lands, assuming topographic forms and conditions to have been even 

 moderately uniform and similar to that over the area adjacent to the 

 shoreline. Hence not only directl}', but indirectly, are we led to the con- 

 clusion that these bars have been built up by material thrown Tip from the 

 bottom of the lake by waves. 



The barrier bars at Wellers bay, Big Sandy bay (West lake), and Little 

 Sandy bay (East lake), in Prince Edward county, are also barriers of 

 this class. There is reason to believe that the amount of material that 

 could possibly have been supplied by the adjacent headlands would have 

 been too small to construct them. They also have probably been built 

 from waste cut by the waves from the bottom above wave base. 



The form of the shoreline here produced is an excellent example of the 

 tendency of shore processes to reduce a complex shoreline to as relatively 

 a simple form as possible during the initial stages of its history. 



