Conjugate Sets of en Echelon Tension Fractures in the Athens Limestone at Riverton, Virginia

Insights into the mechanics of en-échelon sigmoidal vein formation using ultra-high resolution photogrammetry and computed tomography

“…2). Beach (1975), drawing on prior work by Shainin (1950) and Riedel (1929), proposed a kinematic model in which Mode I fractures developing within an existing shear zone become progressively rotated by simple shear, while their tips continue to propagate parallel with the maximum compressive stress axis, and hence develop a sigmoidal geometry (Fig. 2a).…”

The nucleation and evolution of Riedel shear zones as deformation bands in porous sandstone

“…Although it is unlikely that Z1 bands initiate as purely tensional features, the following discussion of Z1 bands possibly nucleating as tension fractures is included due to the geometric similarly of PRZs and tension fracture arrays composed of sigmoidal gash fractures (e.g. Shainin 1950, Plates 1-2). Please note that the alternative interpretation may also apply to 12 bands.…”

Geology of the Stroudsburg quadrangle and Adjacent areas, Pennsylvania--New Jersey

“…The movement picture is corroborated by the orientation of the fractures (for example, see Shainin, 1950). The cleavage is perpendicular to the last-formed part of the tension crack, thus also perpendicular to maximum compressive stress.…”