116 ROYAL SOCIETY OF CANADA 
Chazy, Black River and Trenton formations. rom the village of 
Tetreauville, west of Hull, where it crosses the Ottawa river it takes a 
south-east course and extends through the north-east corner of the town- 
ship of Nepean and thence diagonally across the township of Gloucester 
and the north-east part of Osgoode into Russell. South of the Rideau, 
it involves the Utica, which is brought into contact with the Chazy 
shales, and, further south, the break increases and the Utica and Lor- 
raine shales are brought into contact with the Calciferous limestone. 
In Osgoode apparently the shales of the Medina are affected, as at one 
point these are seen in close proximity also to the Calciferous. 
In Russell the course of the fault is again changed to the east, and 
the grayish Lorraine shales first, and then the Utica are in contact on 
the north side with the Calciferous, Chazy, Black River and Trenton on 
the south, for some miles, till the great drift-covered basin of the Tren- 
ton-Utica is reached, where the sands and clays again prevent the actual 
tracing of its position. 
In the area between this south fault just described and that seen 
near Rockland on the Ottawa river, a distance across the measures of 
about twenty miles, there are no indications of heavy faults at the sur- 
face though several low anticlines occur in this interval. 
Along the shores of the Ottawa river, as at Ottawa city and below 
towards Rockcliffe park, several local faults are seen in the cliffs which 
border the south shore of the river in this direction. Some of these 
are local and affect merely the beds of the Trenton formation, but others 
show a considerable displacement of strata. The most important of 
these is seen on the shore near Governor’s bay. ‘This fault affects the 
Chazy and Trenton limestone, and apparently cuts out the Black River 
at this point. About half-a-mile inland, near the entrance to Beech- 
wood cemetery, what is presumably the extension of this break is seen. 
It here involves the rocks of a higher horizon and brings the Utica shales 
against the Chazy limestone. This fault is apparently local, since 
further east the several formations succeed each other in regular order. 
To the west of Ottawa several important faults are seen. One 
of the most important of these is that noticed in the townships of 
Nepean, Huntley and Fitzroy, and is supposed to represent the western 
prolongation of the Rigaud main line of fracture. 
On the Richmond road south of Bell’s Corners toward Fallowfield, 
a well-defined contact is observed between the Potsdam sandstone and 
the base of the Trenton limestone. The line of fracture can be traced 
south-east from this point for a couple of miles, when the Trenton beds 
disappear and the break affects only the limestones of Calciferous age. 
East of this place the country is largely drift covered, but it is presumed 

