Sandy shorelines exposed to very oblique wave incidence can be unstable and develop self-organized shoreline sand waves. Different types of models predict the formation of these sand waves with an initially dominant alongshore wavelength in the range 1–10 km, which is quite common in nature
CitacióVan den Berg, N. [et al.]. On the mechanism of wavelength selection of self-organized shoreline sand waves. "Journal of geophysical research", 26 Març 2014, vol. 119, núm. 3, p. 665-681.