48 



NEW YORK STATE MUSEUM 



but from favorable points of view the original plain of the delta 

 can be recognized. 



Oneida lake lowland. It seems likely that considerable areas of 

 the lowlands east of Syracuse and north of the channels shown on 

 plates 4 and 5 are more or less filled with deposits largely derived 

 from the latest proglacial streams and from the deltas left in the 

 north-leading valleys. The distribution and leveling of the mate- 

 rials on the plain may be largely referred to the waters of Lake 

 Iroquois, which for some thousands of years stood here at an 

 altitude marked today by gravel bars and spits with altitude of 

 440 to 450 feet. The later land drainage has also spread its load 

 of detritus over the Iroquois bottom or carried it into Oneida lake. 



Theoretic succession: summary 

 Theoretical succession of deposits. An ideal vertical succession 

 of the various deposits in the district from top to bottom would 

 be somewhat like the following, although in any actual section 

 some numbers would be wanting and numbers 3 to 6 would be 

 commingled. In order of time the deposits are the reverse of the 

 numerical order. 



1 Modern vegetal accumulation ; peat 



2 Marl, in places beneath the peat 



3 Flood plain silts from post-Iroquois land drainage 



4 Iroquois silts from land drainage 



5 Iroquois gravels, sands and silts from erosion of glacial 

 deltas 



6 Gravels and sands directly from the glacial outwash and 

 proglacial drainage 



7 Till, ice-laid drift, directly from the glacier 



8 Modified drift, gravels, sands etc., by lakes and streams 

 during the later ice advance 



9 Probable deposits, both ice-laid and water-laid, of an earlier 

 ice invasion, perhaps a Pre-wisconsin glacial epoch 



ic Geest, or products of preglacial rock decay, in place 

 11 Sound or live rock 



Resume of delta characters. If the reader or student would 

 examine one of the deltas which might be misinterpreted, or per- 

 haps mistaken for moraine, he might well visit the one west of 

 High Bridge and a mile south of Fayetteville ; or the one just 

 west of Manlius; or the one across Butternut creek from the Rail- 

 road channel; or any of the terraces in the Marcellus, Cedarvale 



