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NEW YORK STATE MUSEUM 



eastward to the creek and they show variable dips of from 5 to 

 1 5 a little to the south of west. The rocks in the creek bed on 

 the upthrow side of the fault are middle Trenton limestones. A 

 short distance away from the fault plane these rocks are highly 

 inclined showing a uniform maximum dip of 35 a little to the east 

 of south. Continuing southward to the bridge higher and higher 

 Trenton strata are seen and the dip gradually diminishes to 12 . 

 Below the bridge the dip continues to decrease until finally at about 

 150 yards the strata lie in a horizontal position and the coarse lime- 

 stone of the uppermost Trenton is visible at the top of the gorge. 

 Still farther southward the rocks dip northward at a low angle. 



In the immediate vicinity of the fault and on the upthrow side 

 the rocks are highly crushed and folded. This crushed zone is 



C fee K Level-* 



ree t 



Fig. 3 Section showing the condition of things at the,fault near Prospect. Looking south- 

 west and parallel to the fault plane 



about 40 feet wide [see fig. 3]. The rocks on the downthrow side 

 are not crushed and the fault plane is shown as a smooth clean 

 break [see pi. 7]. Along the fault plane slickensides are common 

 and also fault breccia made up of limestone fragments which have 

 often been recemented by white coarse crystalline calcite. On 

 both sides of the main fault plane there are a number of fault 

 slips of very small throw which represent minor fracturing in the 

 immediate vicinity of the main fault. Except for a slight south- 

 westward dip the strata at Prospect falls show no sign of disturb- 

 ance. 



Because of the existence of the wide crushed zone on the upthrow 

 side the character of the folding in that zone can not be determined. 

 Hence the exact throw of the fault can not be given although it 

 can be fairly well approximated. As a result of the faulting the beds 

 of the middle Trenton have been brought up to the level of the 

 coarse crystalline beds of the upper Trenton and hence the fault 

 must be of the thrust or reversed type. A measurement by the 



