The “Limestone with Pelagic Bivalves” (Lower-Middle Jurassic) consists of well-bedded, white or pinkish limestones. This lithology is composed of over 90% tiny bivalve shells (lamellibranchs). The convoluted (not horizontal) stratification that can be observed is the result of a synsedimentary event that took place in the deep ocean, as the sediment slid and was deposited along an irregular slope. This is a process known as submarine collapse (‘slumping’ or ‘gravitational folding’). After this event, regular deposition of sediment continued, forming undisturbed parallel layers.
Credits: UAV-based survey and photogrammetry processing are provided by Fabio L. Bonali.
References
- Oppizzi, P., Pasquaré Mariotto, F., Stockar, R., Stella, A., Corti, N., Pedicini, M., … & Bonali, F. L. (2023). Geosites in the Gole della Breggia Geopark, Ticino, Southern Switzerland. Resources, 12(10), 122. Geosite (stop) n. 2.