REPORT OF THE STATE PALEONTOLOGIST 1902 



1215 



The western limb of the anticline has not been explored to a 

 ■sufficient depth in the Spring quarry to enable us to state defi- 

 nitely what becomes of it, and whether or not it is truncated 

 by a fault in the same manner as are the veins in the other 

 quarries to the south. There are on the surface of the ground 

 some indications of a fault of northeast trend that crosses 

 Delaware avenue at a point about 400 feet west of where the 

 tram track crosses the avenue at the angle, but the plane of a 

 fault intersecting the surface of the ground at this point would 

 pass several hundred feet west of the strike of that deep fault 

 which truncates the veins of the Level and other quarries. 



The eastern limb of the Spring quarry anticline presents 

 much the same features as shown in the other quarries. 



On the surface of the ground the anticlinal arch shows finely 

 in the Delaware avenue quarry and in the stripped area west 

 of the shaft house at the Spring quarry incline; and an ex- 

 cellent sectional view of it looking in a southwest direction can 

 be obtained on the flats from the old floor of the Spring quarry 

 at the foot of the hill near the junction of Delaware avenue and 

 Crane street. In the Spring quarry face and in the face of the 

 Delaware avenue quarry, which lies above the Spring quarry, 

 a continuous, undisturbed section of the Siluric and Lower 

 Devonic formations as far as the New Scotland beds can be 

 measured. The entire thickness of the Manlius and the under- 

 lying cement beds is shown in the face of the old Spring quarry, 

 and the base of the Coeymans limestone is seen breast high 

 above the floor of the Delaware avenue quarry. On the south- 

 east side the beds dip steeply toward the flats. The crest of 

 the anticline is broad, so that the floor of the quarry is almost 

 flat, and at the quarry face the beds show a slight dip to the 

 northwest at the top of the western limb of the anticline. 



On the south side of Delaware avenue, between the Spring 

 quarry shaft house and the engine house [pi. 3, sec. 3], is a small 

 knoll of Manlius limestone, the beds of which dip about 30° 

 toward the southeast. This knoll presents a fine example of 

 "imbricated structure,'' or " schuppen-structur " induced by 

 several nearly parallel minor thrusts from the southeast. 

 These thrusts are peculiar in that their planes, which are from 



