ANALYSIS ON THE TIELING FORMATION CHARACTERISTICS OF MARBLE SHEATH FOLDS AT YANGSHIGOU

In the marble of Tieling formation at Yangshigou, the sheath folds that are perpendicular to the maximum principal strain axis X and perpendicular to the intermediate strain axis Y are found and the deformation characteristics and mechanics are analyzed in the paper.The results show that sheath folds reflect the ductile shearing direction generally in SSE direction 150°~160°, and formed later than formation time of the marble of Tieling formation.