Underground tubular karst features, observed in an arid envinronment of southern Morocco, are described. On the basis of various evidences, it is suggested that such features were originated mainly by condensation water. A computation of the time necessary for their formation supports this hypothesis.
Castellani, Vittorio and Walter Dragoni.
Evidence for karstic mechanisms involved in the evolution of Moroccan hamadas.
International Journal of Speleology,
Available at: http://scholarcommons.usf.edu/ijs/vol15/iss1/5