Flysch formations are sedimentary rock sequences characterized by alternating layers of sandstone and shale. These formations typically develop in deep marine environments, where sediments accumulate rapidly due to tectonic activity, such as the collision of tectonic plates. The layers can vary in thickness and composition, reflecting changes in sediment supply and depositional conditions over time. Flysch is often associated with mountain building processes, particularly in regions like the Alps and the Carpathians. The presence of flysch can indicate past geological events, such as subduction and orogeny, making them important for understanding Earth's geological history and the evolution of landscapes.