502 Matthew — Post-Glacial Faults in New Brunswick. 



from 60° to 80° to the S.E. But these faults are traversed by 

 diagonal ones, some with a course approximately N. to S. and 

 others E. to Wj. The principal movement of faulting in post- 

 glacial times has been along the fault planes that have a N.E. 

 to S.W. course. 



The place where these faults were first observed was on the 

 side of City Road, north of the City Hospital. Here a gla- 

 ciated surface of slate about twelve feet wide has been exposed 

 by the removal of the surface soil. There are nine fau^s 

 visible here having a course nearly parallel to that of the street 

 and a hade to the S.E. They vary in downthrow from one 

 quarter of an inch to four inches, the downthrow being in all 

 cases on the north side. 



Beside these faults of the northeast and southwest system, 

 two faults diagonal to these were seen, these have a course 

 approximately N.E. to S.W. and the downthrow in both cases, 

 though small, is on the north side. 



On the steep hillside east of the end of Charles Street, numer- 

 ous small faults of the N. E.-S.W. system were seen. In all 

 these the downthrows were on the north side. Here the diag- 

 onal faults are of more importance as regards the downthrow 

 that at the exposure on City Road ; the hade of these faults 

 is also less, being about 50° ; the course of these is different 

 from that of the diagonal faults at City Road being approxi- 

 mately E.-W. The downthrows here are on the north side of 

 the diagonal faults and on the north side of the faults that 

 have (approximately) a northeast to southwest course. 



The best display of the S.E-jST.W. post-glacial faults that has 

 been observed is that on Rock street behind Fowler's Mill 

 where a space of about one hundred and seventy feet of slate 

 ledges has been laid bare. In this space sixty-one faults were 

 observed which had been attended with displacement of the 

 measures since their glaciation. In all of these faults, with one 

 exception the downthrow was on the north side, and the hade of 

 the faults was to the southwest. The sum of the displacement 

 at these faults was five feet eight inches ; the average throw 

 for each fault being thus somewhat over one inch. 



In one case only, a fault of half an inch had a downthrow on 

 the south side. The diagonal faults which are not very con- 

 spicuous at this place, were not measured. 



The heaviest throw seen at this place was five inches and 

 very often an individual fault when traced along its course was 

 found to vary in the amount of displacement. This was espe- 

 cially the case when the fault was complicated with a diagonal 

 displacement, so that wedges of the slate would be raised above 

 the general contour, or depressed below it ; and occasionally a 



