(a) and (b) Uninterpreted and interpreted panoramas of the Astoin megaflap and its southern continuation which forms an allochthonous salt sheet during the Jurassic. (c) Anolague onshore salt sheet in the Sivas Basin in Turkey (picture from JC Ringenbach). (d) Analogue offshore salt sheet in seismic line in the Gulf of Mexico. The Astoin allochthonous salt sheet ((a) and (b)) presents the same features of salt sheets ((c) and (d)) which are: a contact which climbs upward into the stratigraphy between the allochthonous salt and its substratum and the undeformed monocline of the substratum below the salt sheet.