390 PLEISTOCENE OF INDIANA AND MICHIGAN. 



The deltas of Lake Wayne do not protrude so far into the lake bed as do those of the earlier 

 submerged stages, and it would hardly be expected that they would, for the Wayne beach is 

 farther from the high ground and the streams naturally brought less gravel to it. Waves and 

 shore currents distribute fine sand more easily than gravel, and deltas of sand are not so likely 

 to protrude where the stream enters on a rectilinear shore. 



The delta of Huron River at the time of the Wayne beach is south of Romulus and shows 

 well-marked protrusion for a mile or more on both sides of the river. This deposit, however, is 

 largely coarse sand and fine gravel. 



Other deltas associated with the Wayne beach show less protrusion. On Clinton River at 

 Utica the earlier delta of Lake Arkona protrudes very strongly, and the stream issues from the 

 apex of the older deposit. ,On this account the sediments brought down later were exposed 

 to powerful currents from the southwest and from the north and in consequence were constantly 

 swept away, mainly to the north, and built into spits and bars that run northward into the 

 depression north of Disco. A smaller quantity was carried to the southwest. These features 

 near Utica are shown on the map of the Rochester quadrangle. 



In strong contrast, the Warren (Forest) beach, which lies 20 or 25 feet above the Wayne, 

 is strongly developed and sharply defined wherever it is composed of gravel and, like the 

 Whittlesey beach, which it resembles in many ways, shows no evidence of modification by 

 submergence. 



RELATION TO LAKE WARREN. 



It is concluded, therefore, that the Wayne beach was made before the Warren, when the 

 lake waters stood at a lower level, and that this beach was submerged under the waters of Lake 

 Warren and was modified by the overpassing waves of that lake. The materials of the Wayne 

 beach in the gravelly district especially were largely removed and swept up the slope to be built 

 into the Warren beach. 



Lake Wayne, therefore, preceded Lake Warren in the same way that Lake Arkona pre- 

 ceded Lake Whittlesey and the cause was probably the same, namely, a readvance of the ice 

 front closing the outlet of Lake Wayne and raising the waters to the level of the Warren beach. 

 There is thus added one more set of facts indicating oscillation and readvance of the ice front 

 in the general retreat. 



ALTITUDE OF WAYNE BEACH. 



In the area of horizontality the Wayne beach has an altitude of about 660 feet, its crest 

 being shown a little above the 660-foot contour on nearly all of the Survey's topographic sheets. 



In the Rochester quadrangle it does not appear to begin to rise northeastward so soon as 

 the Maumee beaches. Indeed, where it leaves the quadrangle 2 miles southeast of Washington 

 its altitude is 663 feet or possibly 1 or 2 feet higher. A mile toward the southwest the crest of a 

 fight bar of this beach half a mile west of the main ridge has an altitude of 665 feet, not percep- 

 tibly higher than its altitude farther south. Even at Hickey, in St. Clair County, the altitude of 

 the station is-given as 660 feet and the crest of the beach is only 2 or 3 feet higher. The profiles 

 of the Pere Marquette Railroad on both lines running out of Port Huron are, however, known 

 to be less accurate than could be desired. Where the Port Austin branch crosses the Wayne 

 beach in northeast sec. 1 1 , Clyde Township, the altitude of the beach is between 670 and 685 feet, 

 more accurate measurement not being available. The rise of the other beaches in this district 

 is at first a foot or less per mile. Hickey is about 14 miles south of the point mentioned. The 

 rise of the Wayne beach, therefore, probably begins not far north of Hickey. North of this 'to 

 the north line of Sanilac County no reliable measurements of this beach are available. Several 

 measurements by aneroid barometer were made, but they show so much discordance that they 

 are probably not of much value. One mile from the north line of Sanilac County four faint 

 strands which are thought to represent the Wayne beach were found by wye levels run by 

 Mr. Leverett to have altitudes of 727.5, 722, 721, and 717.4 feet. A faint beach crossed by the 

 railroad 2 miles north of Ruth at an altitude of about 740 feet is thought to be the Wayne, 



