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Outerops of bituminous sands occur in the lower courses of many of the
tributaries of the Athabaska. Difficulties of transportation would, however,
militate against the development of numbers of these.

On Horse creek, in the lower 54 miles of the valley, exposures are seen that
indicate the presence of a very large tonnage. “ Much of this, judged by material
seen in outcrops, and apart from grading of mineral aggregate, is of commercial
grade; but probably not more than four or five outcrops are so situated as to
permit of practical development. The areal extent even of these, is limited by
the narrow and precipitous nature of the valley.”

There are difficulties in the way of transportation. “ At alternate bends
in the stream, where the current impinges against the banks, the possibility ot
heavy clay slides must be taken into consideration. Points opposite such cut
panks are, however, usually low and free from tlie effects of slides.”

On Clearwater river, which flows through a larger valley than the Athabaska,
only one exposure is seen for 20 miles above the mouth, although there is little
doubt that the bituminous sands extend many miles up the river and are obscured
by drift and forest growth. The outcrop occurs on the north shore a quarter of
a mile west of the mouth of Hangingstone creek. The maximum thickness
exposed is 20 feet, and the bitumen content and the grading of the mineral
aggregate vary greatly.

On Hangingstone creek, which occupies a deep, notch-like valley, there are
outcrops at ‘nearly every bend along the first 5 miles. It may be that by careful
exploration some points will be found at which quarrying operations can be
carried on successfully.

On Christina river, twenty-four exposures were noted, but measurements
were made of only seven, the others being eliminated owing to heavy overburden,
prevalence of clay slides, and the presence of impure partings in the bituminous
sand itself. The depth of the overburden would be a serious handicap in the
development of deposits along this river. “ Topographically, the valley of the
Christina river resembles that of Horse creek. Its course is, however, more
direct and the small areas of bottom lands are consequently fewer............14
is probable that better grades and a better alignment can be secured than on
either Hangingstone or Horse creeks. Owing, however, to the unstable and often
precipitous character of the banks, it is very doubtful if, even here, a surface line
could be maintained within the valley itself.”

On Steepbank river, which enters the Athabaska 214 miles below McMurray,
a number of promising outcrops occur. Details are given in the following table
concerning nine of the more promising outcrops of the twenty-six seen. —

“ Based on surface indications, the deposits of bituminous sand on Steepbank
river may be considered quite as promising as those seen on any other stream
in the McMurray district. Owing to the sandy and gravelly character of much
of the overburden, there is a general absence of the heavy clay slides so frequently
met with on some of the other streams. Such a consideration is of importance
in considering possible development and transportation within a narrow valley.”

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