4 
MUSEUM BULLETIN NO. 4. 
South Fork Oldman river (commonly called the Southfork 
river), and the most northern outcrops noted by Dawson are 
on the Northwest Branch North Fork Oldman river. On 
the Southfork river, the width of the area underlain by these 
rocks is some fourteen miles; this width narrowing somewhat 
to the north, where the volcanic area lies wholly between the 
Livingstone range on the east, and the main range of the Rockies 
on the west. The area in which outcrops occur at the present 
time is about 500 square miles, and from considerations to be 
mentioned later (see p. 10) it is thought that a somewhat 
larger area was originally subjected to the deposition of the vol- 
canic material. 
The most accessible outcrops of these tuffs at the present 
time are on York creek, about two miles west of Blairmore, 
Alberta, where several varieties may be seen; and about a mile 
west of Coleman, Alberta, where other very massive types are 
well exposed on the main highway through the pass. 
GENERAL GEOLOGY. 
STRATIGRAPHY OF THE CROWSNEST VOLCANICS. 
Stratigraphic Position . 
The stratigraphic position of the volcanics is shown in the 
following section of the measures in the eastern foothills where the 
volcanics are found. 
Superficial Deposits. 
Pleistocene and Recent. 
( Unconformity ) 
Allison formation (Belly River) .... +2000 ft. 1 
Benton formation 2700 
CROWSNEST VOLCANICS 0-1150 “ 
Dakota( ?) formation 2500 “ 
Kootenay formation 600 “ 
Fernie formation 600 “ 
Upper 
- Cretaceous 
Lower Creta- 
ceous. 
Jurassic 
^Thicknesses approximate. 
