10 July 2015

Friday fold: Lawson Syncline and Mount Inflexible

Posted by Callan Bentley

View of Lawson Syncline looking obliquely along strike (SSE) from an unnamed peak SW of Mount Inflexible, Kananaskis Range, Alberta. The axis of the syncline forms the bottom of the valley and plunges slightly toward the south. The syncline is in the hanging wall of the Sulphur Mountain Thrust sheet. On the right side of the photo, beds can be seen dipping to the right (west) in the ridge the photographer is standing on, evidence of the adjacent Kent Anticline, whose axis is eroded but would be above the right side of the valley. Rocks are Carboniferous to Permian Etherington Formation to Rocky Mountain Group carbonates and clastics on the flanks of the folds and recessive Triassic clastics of the Sulphur Mountain Formation forming the core of the syncline (now mostly eroded; remaining beds are most vegetated, down-valley).

Allen FF 3

Of course, that’s another gem from longtime reader and contributor Howard Allen. Thanks, Howard!