This picture that shows a small amount of the massive breccia zone is at a pullout at the Fairmont welcome sign pullout at N50 20. 131 W115 51.353.
The massive breccia zone, can be seen for about 7 K north of Fairmont as easily spotted by looking at the bowl immediately to the south of IndianHead Mountain. This picture was taken at highway pullout N50 22.021 W115 52.194.
This picture that shows the massive breccia zone is at a pullout off Westside Road at N50 20.653 W115 53.653. There are two transverse faults in this picture plus one immediately to the right, ie South of the picture, which runs down where Fairmont Creek is and is the source of the Hot Springs.
The Stanford Range is one of the western ranges of the Rocky Mountains and is divided into three distinct blocks divided by two longitudinal faults, the Redwall and the Stanford which extend throughout the length of the range. This range is between the wide valley occupied by the Kootenay River and the Rocky Mountain Trench. Western fault block rocks are sedimentary and range in age from late Precambrian to middle Devonian. The Western fault block is different than the other two inasmuch as the folds are overturned towards the southwest instead of the northeast with the structural trend about 10 to 15 degrees oblique to the trend of the Rocky Mountains and the Rocky Mountain Trench.
The Redwall Fault is also intersected by oblique or transverse faults and some of these can be seen by observing the drainage creeks, especially the one that runs down Fairmont Creek and is the area where the hot springs emerge. This fault allows for the hot springs at Radium where the breccia is very pronounced right beside the road.
This Redwall Fault is normally thought of as being only in Radium and very little literature is available, even though it is a significant structural boundary between the Porcupine Creek Fan and the Purcell Anticlinorium (WK Foo 1979) This fault runs about 70 miles long from around Canal Flats to Brisco where it disappears under alluvium on the floor of the Rocky Mountain Trench where it is projected north for another 30 miles. At the south end, about 8 miles north east of Canal Flats the Mary Anne Fault converges with the Redwall fault at a major gypsum deposit. The Mary Anne Fault joins the Stanford Fault near the Pedley Pass.
While the Rocky Mountains were primarily formed by thrust faults, there is about 10 miles of noticed strike slip action. The major faults in California are strike slip, for example the San Andreas.The strike-slip movement indicates that the west side was upthrown about 1000 to 3000 feet relative to the east side. It appears to be an oblique slip in which the horizontal component was very much greater than the vertical.
Diagram of Strike Slip fault
The Redwall Fault breccia zones, of bright red, yellow and buff can be seen with the naked eye and a very prominent zone can be seen at the Fairmont Ridge. This zone is massive, around 1,000 feet wide and larger than the one seen in Radium. The Redwall breccia can be seen through out the length of the fault from Canal Flats to Radium. The breccia is bright red hematite-stained limestone, minor amounts of iron oxide, random amounts of quartzite and dolostone or conglomerate that resists erosion and forms steep sided ridges and pinnacles. Most of the dolomite has been replaced with calcite and quartzite and the presence of hematite indicates a hydrothermal origin. The breccia consists of sub-rounded fragments ranging in size from a fraction of an inch to more than 10 feet and the breccia zones in most places is about 200 feet wide. Nearly all fragments, particularily in the center of the breccia zones, are partly shattered and cemented with calcite and hematite while the zones of intense shearing usually weather a darker red than the surrounding breccia.
Acknowledgements to: B.C. Pearce (Geological Field Guide to The Southern Rocky Mountain Trench; E Swanson, College of the Rockies; W K Foo Masters thesis Queens University 1979, BC Government publications
To log this Earthcache, please email the owner with the following: a) the vertical length of the breccia out crop seen at Fairmont b) comment on the different colours of breccia that you see c) What is the estimated total length of the fault line known as the Redwall Fault. d) Can you see other areas of breccia from this viewpoint and if so what colours?
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