THE ORDOVICIAN ROCKS OF LAKE TIMISKAMING. 
7 
shales at Cabot head. The alternative correlation appears to 
be that these shales are of Ordovician age perhaps belonging 
to the Cincinnatian group. 
(2) With the age of the shales in doubt, the data bearing 
upon the relations of the Silurian and Ordovician formations are 
rather meagre. We will first turn to Chief island. To explain 
the occurrence of both Niagara and Trenton fossils in the dolo- 
mites resting in the irregularities of the Huronian, only one 
hypothesis appears adequate. That is, this resistant knob was 
washed by both Trenton and Niagaran seas, practically all of 
the Ordovician deposits being eroded away before the Niagara 
deposits were laid down. 
The proximity of Niagara and Black River strata on the 
beach at Hailey bury admits of a different explanation as already 
stated. The Black River outcrops west of Hailey bury are 185 
or more feet (based on elevation of Haileybury station) higher 
than the deposits near lake level, most of which are basal Nia- 
garan. At Dawson point the basal Niagaran beds are 110 feet 
above the lake. Thus in the case of strata that are gen- 
erally horizontal there is evidence of considerable differential 
movement including such faulting at least as is found near 
Haileybury, That a part of the difference of elevation may be 
due to irregularities in the floor upon which the sediments 
were deposited, is probable, but the conditions at Haileybury 
are certainly due, for the most part, to later movements. This 
conclusion is in accord with the statement by Dr. W. G. 
Miller 1 — “Along the wagon road, in lots 5 and 6 in the 3rd 
concession of the township of Dymond, to the northwest of the 
town of New Liskeard, the limestone cliff presents a striking 
face, indicating faulting. The fault line is continuous with the 
western shore of Lake Timiskaming, and furnishes still further 
evidence confirmatory of the theory that the lake lies along a 
great northwest-southeast fault.” 
It seems probable that Chief island and Dawson point are 
also separated by a fault. 
1 Report of the Bureau of Mines, Vol. XIX, Pt. II, p. 108. 
