223 



that other disturbances were connected with it and that the actual 

 contact which he has found presents some interesting features. 



Extent of the Fault. — While I have not yet been able to trace the 

 fault to the borders of the State at either of its extremities I have been 

 able to trace it far beyond its mentioned boundaries and feel confident 

 that the particular disturbance under discussion extended from the 

 Ohio to the Wabash along the western border of the Knobstone outcrop 

 and perhaps beyond. Tracing the fault south of Campbellsburg- in 

 Washington County is difficult because the area on each side of the 

 rift is occupied by limestone. 



Along the northern end of the displacement glacial deposits conceal 

 the bedrock to such an extent as to render observation difficult. Undei. 

 these circumstances the best that can be done is to trace the disturbance 

 by the reversal of dip of the limestones, as the finding of the rift will 

 be extremely difficult. By such observations as it was possible to make 

 I have traced the disturbance from a point southeast of Campbellsburg 

 in Washington County to a point northwest of Waveland in Montgomery 

 County. 



Rift. — The actual contact of the rocks along the fault plane is 

 revealed in only a few places. There are numerous places where the 

 harder, more resistant sti'atum of limestone stands forth like a wall on 

 one side of the rift, but the opposite side is occupied by mantle rock 

 which was derived by the weathering of the Knobstone and which con- 

 ceals the actual rift. Excavations made at such places would doubtless 

 reveal the actual contact of the limestone and the Knobstone. 



In a few localities the rift is exposed and the plane of the fault 

 is bordered on the one side with limestone and on the other by shale. 

 One outcrop of the rift zone was found in the bed of the north fork of 

 Leatherwood Creek near Heltonville. At this point the Knobstone 

 occurs on one side of the fault plane and the Harrodsburg limestone on 

 the other. The line of rift is distinct, being marked by a thin bed of 

 breccia. The brecciated zone is composed mainly of fragments of lime- 

 stone in which small fragments of shale are intermingled. These frag- 

 ments have been cemented together with calcite and the whole zone more 

 or less marbleized. In a cross-section of the brecciated rock the veins 

 of calcite stand out clearly, as they are whiter than the fragments of 

 limestone and shale which they bind together. Small quantities of 



