Miotlaste i muszlowe struktury na ekstensyjnych powierzchniach spękań piaskowców środkowego turonu w Górach Stołowych, w Sudetach

Newely discovered well preserved plumose and conchoidal structures on the large joint surfaces of sandstone in the Sto³owe Mountains are interpreted in terms of tensile features. Multiple generations of the isochrones on the conchoidal surfaces suggest repeated propagation of the deformation front. Described tensile joint surfaces represent only one of several stages of deformation caused by stress relaxation of the Sto³owe Mountains platform. It is assumed that main directions of tensile strain in the area were predisposited by the framework of dislocations and joints in the crystalline basement of the area (Jerzykiewicz et al., 1973). Three others solutions are also discussed.