radar stratigraphy taken from the radar reflection profiles allows various deposits to be identified. These have resulted from overwashing, overtopping, sedimentation across the whole of a seaward dipping beachface or berm ridge welding onto the upper beachface. Each chenier is characterised by a different spatial arrangement of these four basic depositional units. Coastal plain of French Guiana, Suriname and Guyana An extensive complex of beach ridges and swamps (ritsen en zwampen in Suriname) was formed between the mouth of the Amazon river and the Orinoco on the coastal plain of the Guiana Shield. References See also Deposition (geology) Beaches Coastal and oceanic landforms