32 NEW YORK STATE MUSEUM 



ville southward where the shale is thickest and the slope is not so 

 great. An interesting erosion remnant, or outlier, separated from 

 the main mass covers several square miles in the vicinity of Locust 

 Grove. 



The Utica shale is here not highly fossiliferous although certain 

 fossils so common to the formation may he found in nearly every 

 exposure. Among these aretheEndoceras proteiformc 

 of the chambered cephalopods, Triarthrus becki of the 

 trilobites, and some graptolites. Animal life in the Trenton ocean 

 was very prolific, but with the advent of the muddy Utica sea there 

 was a great diminution in both the number of species and 

 individuals. 



Along the line of outcrop the shale shows a notable and steady 

 decrease in thickness toward the north. Following are approxi- 

 mate determinations of the thickness within the quadrangle from 

 south to north. 



Feet 



Along Moose creek 300 



At Constableville 260 



At Turin 230 



At Houseville 200 



Along Atwater creek 180 



Southeasterly along the line of outcrop the Utica increases in 

 thickness. Near Remsen it is over 300 feet and near Little Falls 

 about 600 feet. Westward in Oswego county it shows a thickness 

 of 180 feet at Central Square; 120 feet at Fulton and 113 feet at 

 Stillwater in the deep wells. Thus it is evident, in a general way 

 along the southwestern Adirondacks, that the Utica is thinnest 

 where the Trenton is thickest and vice versa, the two formations 

 having nearly the same thickness on the Remsen quadrangle. 



Lorraine shales and sandstones 



The Lorraine formation received its name from the town of Lor- 

 raine in Jefferson county, some 30 miles northwest of Port Leyden. 

 The rocks included under this heading are the same as those of the 

 old " Hudson River group " of Vanuxem's report.^ In the future 

 the Lorraine beds will doubtless be subdivided, but more detailed 

 work over a wider territory must be done before such subdivision 

 is attempted. In the meantime, all the strata lying between the 



1 Geol. N. Y. 3d Dist, 1842. p. 60. 



