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

Abstract

Plumose and conchoidal structures on the joint surfaces of the Middle Turonian sandstone of the Stołowe Mts.,Sudetes (SW Poland).A b s t r a c t. Newely discovered well preserved plumose and conchoidal structures on the large joint surfaces of sandstone in the Stołowe Mountains are interpreted in terms of tensile features. Multiple generations of theisochrones on the conchoidal surfaces suggest repeated propagation of the deformation front. Described tensilejoint surfaces represent only one of several stages of deformation caused by stress relaxation of the StołoweMountains platform. It is assumed that main directions of tensile strain in the area were predisposited by theframework of dislocations and joints in the crystalline basement of the area (Jerzykiewicz et al., 1973). Threeothers solutions are also discussed.