134 CHAMPLAIN DIVISION. 



traversed by irregular fractures adjacent to or near the line of contact between it and the 

 Primary rocks. The only ones, however, which I propose to notice, are now in the form 

 of deep gorges, one of which gives passage through it lo the Ausable river at Birmingham 

 in Clinton county ; and the other is in the town of Mooers, in the vicinity of the Pro- 

 vincial line, or indeed it is stated that this line passes through the gorge. In both of these 

 instances, the displacement of the strata is only slight, just sufficient to break their con- 

 tinuity. As has been remarked, they are deep gorges, varying in depth from twenty-five 

 to one hundred and fifty feet. A particular account is given of them in my report of 1842. 

 These gorges do not appear to be connected with metallic or any other veins of mineral 

 matter. They were formed, in the first place, by a slight upheaving, which served to 

 crush or break the strata, forming a line of fracture ; afterwards this broken line became a 

 water course, and the movement of water through it was sufficient to clear out and 

 widen the breach already produced. 



A more interesting and important fault or fracture, however, traverses the State from 

 south to north, and involves in its derangements not only the lower rocks, but some of the 

 Helderberg series. I can only indicate some of the points where it may be observed. 

 One mile south of Kingston, the thick-bedded sandstones of the Hudson-river series are 

 elevated and raised up to the base of the Pentamerus liraerock. The dip of the former is 

 to the east at an angle of 30°, with their edges resting against the horizontal beds of the 

 pentamerus and the upper part of tlie Waterlime series. The exposure at this point is one 

 of the best, in consequence of a cut through both series of rocks, whereby the relations of the 

 masses are satisfactorily revealed. Apparently there is here an unconformity of the Hud- 

 son river series with the waterlimes whicli immediately succeed them : this unconformity, 

 however, is produced by the disturbance of a portion of these rocks only, the conformity 

 remaining with the masses which are undisturbed. Fig. 17 represents the position of the 

 rock at the locality specified, which, to be more particular, is about one mile from Kingston 

 point, at a place where the rock is extensively quarried for cement. 



ViS' 17. 



IL-™''^ 



a. Pentamerus limestone. b. Waterlimes. c. Thick-bedded gray sandstone of the Hudson-river scries. 



We may trace this same fracture north to Saugerties, four miles west of Catskill, and 

 through Coxsackie, New-Baltimore and Coeymans. At New-Baltimore and Coeymans, 

 we may see disturbances of the same kind as those at Kingston point, with the easterly dip 

 of the Hudson-river series, which terminates at once with the waterlimes and pentamerus, 

 the latter retaining their horizontal position. At Catskill, the fracture passes through the 

 Delthyris shales, or affects the whole of the Helderberg division. From Coeymans, this 



