Publisher © Czech Geological Survey, ISSN: 2336-5757 (online), 0514-8057 (print)
Bedding-plane slip movements in Cretaceous sandstones in the Bezděz area
AbstractTectonic deformations of the bedding-plane slip type (also called layer-parallel slip) have been often overlooked in the Bohemian Cretaceous Basin. New examples were identified in the Jizera Formation sandstones (Turonian) in the Bezděz area based on field mapping and tectonic measurement. Their manifestations are lithology-controlled. The slip in quartzose sandstones is accompanied by series of dense en échelon fractures (mostly conjugate Riedel shears) dipping at moderate angles, while that in heterolithic sandstones is dominated by slickensides on the principal horizontal fault plane. Paleostress analysis at Katusice revealed two closely superimposed phases, possibly of Miocene age: an older WNW-ESE compression and a younger NW-SE compression.