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[ELLS] GEOLOGY OF THE OTTAWA PALÆOZOIC BASIN LU LA 
that the line of fracture extends beyond the Rideau river, across the 
southern part of the township of Gloucester, till it meets the Hull and 
Gloucester fault in the northern part of the township of Osgoode. 
At this point in Nepean where the Trenton outcrops cease against 
the Calciferous, another line of fracture meets the Huntley and Nepean 
fault, and extends south into the township of Gouldbourn. This fault 
passes a short distance east of the village of Richmond, and it brings the 
limestones of Black River age, and the two divisions of the Chazy, suc- 
cessively against the Calciferous. Further to the south this break appar- 
ently disappears in the northern part of the township of Marlborough, 
or at least can be traced no farther in this direction. 
The continuation westward of the fault noted as occurring on the 
Richmond road, and which has been described in the Geology of Canada, . 
1863, as the Rigaud and Fitzroy anticlinal, is defined at several points 
in the townships of Huntley and Fitzroy. For a good part of the dis- 
tance it follows the southern outcrop of the ridge of crystalline rocks 
which extends east from Arnprior to within ten miles of the city of 
Ottawa. In the eastern part of Huntley the contact before reaching the 
Archean ridge is between the Potsdam sandstone on the north and the 
Black River limestones on the south. Thence west the Black River rests 
against the old ridge for some distance, extending for nearly two miles 
into the township of Fitzroy, when the underlying formations from this 
down to the base of the Calciferous, successively abut against the rocks 
of the ridge. Its further prolongation westward would bring it to the 
Ottawa river near the town of Arnprior, at which place there is a well- 
defined break between the crystalline limestones of the Hastings series 
and those of Calciferous age. 
A second line of fracture appears in the southern part of the town- 
ship of Huntley and has a course approximately parallel to that just 
described. Like the last also it appears to have some connection with 
a small outcrop of crystalline rocks which show along its course. It can 
be well seen at the village of Pakenham, from which it evidently extends 
both to the east and west. In the former direction it can be traced for 
some fifteen miles into the township of Gouldbourn crossing the southern 
part of Huntley. At Pakenham the rocks in contact on the south are 
Calciferous limestones and on the north the Black River formation. In 
the southern part of Huntley the fracture is well displayed, and the 
presence of a small outlier of Archæan gneiss, limestone and granite is 
noted. Here the rocks of the Paleozoic series are sharply inclined, the 
Potsdam sandstone being in contact with the Black River limestone. 
