GEOLOGY OF SARATOGA SPRINGS AXD VICINITY lOI 



western series has been overridden by the rolHng and sHpping mass 

 of the eastern shales and grits to an extent at present unknown. 

 We have in the sections extended the Canajoharie shale and the 

 underlying limestones and sandstones to the eastern hill region, 

 because from the thickness of these formations at Saratoga it is 

 sure that they continue for a considerable distance eastward under 

 the crumpled shales. Quite probably they descend gradually east- 

 ward under a subhorizontal thrust plane, partly by step faults, 

 such as bring the limestones at Saratoga Springs down to the level 

 of the village (see diagram on left). 



The Canajoharie shales of the western belt exhibit but gentle 

 dips in most outcrops. In the region of the Glowegee the dip 

 is to the west toward the fault and to the southwest, while about 

 Saratoga and on the Schuylerville quadrangle it is mostly to the 

 east and southeast, usually less than 5°. Exceptions are the out- 

 crops on the upper Snook kill, at the foot of Mt McGregor, 

 where the dip is on the average 50° and as high as 65°, owing 

 to the nearness of the McGregor fault line that separates the shale 

 and Precambric rocks. At Gansevoort the shale is already much 

 disturbed by slipping and folding, but in general dips steeply south- 

 west, while at Fort Edward, a few miles beyond the limits of the 

 quadrangle, the dip is about 12° to southeast. Both at Ganse- 

 voort and Fort Edward a great number of small slips occur, and 

 the varying dip to northAvest and southeast indicates that the shale 

 belt is broken into many tilted blocks by faults more or less paral- 

 lel with the master faults, that is, faults running in southwest- 

 northeast direction. None of these larger faults has been directly 

 observed in the shale. Nevertheless their presence can be directly 

 inferred in several places, as at Rock City Falls and half way be- 

 tween North Wilton and Saratoga Springs, where faults pass from 

 the limestones southwestward into the shales. The fault separat- 

 ing Canajoharie and Snake Hill beds at Ballston may also belong 

 in this class. 



Besides these supposed larger faults, a multitude of small slip 

 faults transect the shale. All of these strike northeast, more or 

 less parallel to the master faults, dip slightly to the east and the 

 upthrow side is on the east, all of these faults being of the nature 

 of small overthrusts. The throw is everywhere small, being but 

 a few feet or in some cases only a few inches. Three of them 

 were observed in the lower gorge of the Kayaderosseras, others 

 in the Snook kill near Gansevoort. The best instances of these 



