Abstract
A limestone bed with synsedimentary deformations is described from the Middle/Upper Muschelkalk boundary (Middle Triassic) of Thuringia, Germany. The deformation structures have an elongated geometry in a preferential N–S to NNW–SSE direction and are several metres across in size. They are similar to ball-and-pillow structures but differ from these by absence of significant loading into underlying beds. Their development is interpreted as a result of bed-internal deformation with bed thickening due to lateral contraction and bed thinning due to stretching. This deformation mechanism is comparable to the one producing boudinage structures, in particular pinch-and-swell structures. The deformation style and size of these structures and their widespread occurrence together with other synsedimentary deformation structures support their interpretation as earthquake-induced structures (seismites). Synsedimentary deformation structures are common features that occur in a narrow stratigraphic unit at the Middle/Upper Muschelkalk boundary in different parts of the Germanic Basin and point to tectonically influenced changes in the depositional regime and basin organization. Further examples of pinch-and-swell structures from the Lower and Upper Muschelkalk suggest that tectonics significantly influenced the sedimentation in the Germanic Basin during Middle Triassic time.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.