612 
N 
S 
Figure 6. Summary diagram of lineament directions. 
distribution of such features from satellite imagery 
is that directional trends can readily be identified 
and summarised. 
On the Ghott el Fedjadj spring mound lineaments 
occurred in one main direction, E-W to SE-NW, 
associated with rock subcrops and faulting parallel 
to the fold axes of the Chott el Fedjadj anticline. 
A secondary direction, NNE-SSW, was identified which 
is related to faulting and jointing perpendicular to 
the main fold axis. Wind gaps along the Djebel 
Tebaga are probably associated with this faulting 
and jointing. The aioun field in the Chott el 
Djerid is orientated in a NNE-SSW direction and 
appears to be related to the undercrop of aquifers 
or large scale faulting at the buried nose of the 
Chott el Fedjadj anticline. 
ACKNOWLEDGEMENTS 
Part of this work has been carried out as a NERC 
Studentship GT4/83/GS/87 to one of the authors, 
Arwyn Rhys Jones. We would like to thank Geoff 
Wadge for his constructive comments and to 
Chris Holland, Sheila Dance and Erika Meller for the 
technical preparation of the paper. 
Reconstructed folding 
(Post-Oligocene/ 
Pre-Burdigalien) 
Cross-section 
(from Mamou, 1976) 
Figure 7. 
1976) 
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