GEOLOGY OF SARATOGA SPRINGS AND VICINITY 53 



In front of this low escarpment, at several places along the road 

 leading due north to the Glowegee, small outcrops of dark shales 

 were observed, the shale being sandy in some parts and fissile and 

 argillaceous in others, but nowhere of the character of the Cana- 

 joharie shale. This shale we have mapped with the Schenectady 

 beds.^ 



The Indian Ladder beds. The Schenectady beds are overlain 

 in the Helderberg escarpment at the Indian Ladder by a similar 

 formation, 300 feet or more in thickness, that has furnished a 

 faunule hitherto known only from the Eden beds about Cincinnati 

 and of an age roughly corresponding to that of the Frankfort beds 

 in central New York. This formation, which is of small east-west 

 extension, was deposited after an emergence in Utica time in the 

 narrow southern extension of the western trough. The submersion, 

 however, proceeded probably from the south, and it is very probable 

 that it extended over the Saratoga sheet, although no rocks of this 

 period are left there. 



STRUCTURAL GEOLOGY OF THE WESTERN BASIN 

 BY H. P. GUSHING 



General statement. The Paleozoic rocks of the western basin 

 have been deformed chiefly by faulting, which has equally affected 

 the Precambric rocks. Folds are not prominent and the rocks show 

 but gentle dips, except locally near faults. The district shows little 

 sign of lateral compression and the faults all appear to be normal. 

 In these two respects arises the chief structural difference between 

 the rocks of the western and eastern basins. 



Vanuxem, years ago, described the normal faults which cross 

 the Alohawk valley, from Little Falls to Hoffmans Ferry.- The 

 next geologist to consider them in any detail was Darton, who studied 

 and mapped all the Mohawk faults, especially extending the work 

 north of the river, and also carrying it northeastward to include 

 the Saratoga region."^ This was a most excellent piece of work 

 and has formed the basis for all subsequent investigation of these 

 faults. 



^Professor Miller has, on the adjoining (Broadalbin) quadrangle, mapped 

 the sandstone-shale alternations of the Schenectady formation as Frankfort 

 beds, and the underlying shale of the same formation, as Utica, the Schenec- 

 tady beds having at that time not yet been studied by the writer and separated 

 from the Frankfort shale. 



2 Geology, 3d Dist., p. 203-11. 



3 N. Y. State Geol. T4th Ann. "Rep't. 1804, p. 33-53. 



