The sediments consist largely of sands, silts and gravels. In Flanders, sands, gravels and marls predominate, covered by silts in places. Rice grows on a variety of soils like silts, loams and gravels. Quincy Basin is filled with the eroded gravels and silts from the Coulee. It consists of interbedded sands, clays and silts, with discontinuous clay lenses. The soils usually consist of clays, silts, and sands deposited during floods. High pore pressures occur in soils composed of fine silts or clays. On continental slopes and ridges calcareous silts are found. They also have been observed in lacustrine silts, tuffs, and conglomerates. Fine-grained soils, mainly silts and clays, are classified according to their Atterberg limits. It is where deposits of fine silts and clays settle after a flood. A hydrometer analysis is the process by which fine-grained soils, silts and clays, are graded. Lacustrine material is well sorted and fine-textured, having finer silts and clays. Despite many precautions, the canal silts up with silt from the water supply. The ruins of the Lycian and Roman town are mostly covered by alluvial silts.