Strain analysis of boudinage and ptygmatic folding in the Lily Pond Lake area, Manitoba

Abstract

Boudinage and ptygmatic structures can be observed within a vertical outcrop of amphibolite in the Lily Pond Lake area. Two well-developed joint directions facilitate measurement of the dimensions of the ptygunatic folds and boudinage structure in two directions. Their dimensional measurements are the basis of the interpretation of strain. A study of the boudinage structure provided for extensional strain measurements from which the extensional strain axes of the strain ellipse were derived. A study of the ptygmatic structures provided for the amount of compressive strain the host rock had undergone and from which the compressive axis of the strain ellipsoid was derived...