THE PETROLEUM INDUSTRY OF CANADA 



chemical action on mineral matter at a high temperature 

 in the depths of the earth's crust, or whether it is formed 

 from the decomposition of organic remains accumulated in 

 sedimentary rocks. At present time the weight of 

 evidence is in favor of the latter conclusion, but whatever 

 its origin may be there are a number of conditions in 

 respect to its source and surroundings which must 

 imperatively obtain in order that an oil field of commercial 

 value should be found. 



It is necessary that not only should the original 

 material exist in the locality in liberal quantities, but it 

 should be accumulated into pools in such manner that when 

 the bed is tapped oil will flow sufficiently free to be 

 remunerative. To fulfil these conditions it has been found 

 necessary that, over the rock containing the oil material 

 and that containing the porous matter in which it may be 

 held, an impervious dome-shaped roof of sufficient size and 

 thickness be formed to prevent the escape of the oil under 

 pressure during the ages through which it has been kept. 



When the drill hole reaches the resevoir of oil, if there 

 is a sufficient hydrostatic pressure under the oil, it is forced 

 up and becomes a flowing well, otherwise a pump has to be 

 used to get the crude oil to the surface. 



The rocks of Southern Ontario, from Kingston to the 

 River St. Clair, may be said to be composed of those form- 

 ations belonging to the Upper and Lower divisions of the 

 Silurian system. They are composed of a number of 

 different formations from the Trenton in the east to the 

 Hamilton in the west, the strata dipping in nearly a 

 uniform manner towards the west, the outcroppings of the 

 underlying strata appearing under the overlying drift clay 

 at intervals along the route mentioned. In the uppermost 

 of these strata are situated the petroleum beds on the 

 summit of the anticlinal ridges parallel with the fields and 

 sloping in either direction. The adjoining synclinal 

 hollows in the rock being filled with a black shale, which 



