Enclosed is a rough sketch map based on our HYDRODAT shallow well-log information showing the inferred position of a buried preglacial valley lying to the north and east of the Hamilton Lake oil field. Reported bedrock depths inside and outside the buried-valley boundaries are indicated. The course of the valley in range 9 is uncertain but is probably more tortuous than is indicted on the map. The valley makes its way through the gap between Nose Hill and the prominent hill lying to the north of Nose Hill and centered in the southern part of township 33, range 9. This would give the valley course in range 9 a pronounced S shape.
With respect to water-supply potential of the buried valley, our HYDRODAT information suggests this may be very limited. Except in a few cases, no wells or test holes located over the buried valley encountered permeable materials lying on the valley floor. Where such materials were encountered, the well logs indicate them to be fine grained and in only two instances were they reported to yield water. In both cases drilling was carried into bedrock and eventual production was from bedrock aquifers.
Reported bedrock yields for the area represented on the map range up to 52 igpm (imperial gallons per minute) but fewer than 10 percent exceed 20 igpm and over 70 percent are 10 igpm or less. A concentration of the higher yield bedrock wells is found in the Hamilton lake oil field area as defined by the Oil and Gas Conservation Board. This concentration reflects the experience of the operators with deeper bedrock aquifers and their efforts to construct efficient high-yield wells.