EN
Characteristics of two dune fields is presented in the article. The fields consist of barchans and barchanoidal dunes located south-east of the Chott Jerid. The aim of the research was to describe textural features of aeolian material building selected dunes and to assess the length of the transport and the source of the dune sediments. Granulometrie indices (based on Folk and Ward) and mineral-lithological analysis allow to infer that the researched sediments underwent a long lasting process of aeolian transport. This is proved by a very good sorting (σ₁ = 0,2-0,3) and a relatively small mean grain size diameter (Mz =0,1-0,063 mm). Quartz (mineral highly resistant to mechanical abrasion) definitely dominates in the dune sediments (over 80%) while gypsum (not resistant to abrasion) constitutes only several percent. Allochthonous origin of the dune sediments is also proved by the fact that a local substratum is very rich in gypsum and therefore could not constitute the source of the dune sediments.