Desert lakes: playa lakes and sebkhas
399
Figure 16.14. Salinity zones in a playa surface. Cottonball Basin, Death Valley, California (from Hunt
et al. (1966)).
gypsum are the main factors. Secondary gypsum crystals filling the existing pores increase
the volume and the crystallization pressure is responsible for lateral gypsum expansion
and the appearance of dome morphologies. Calaforra (1996) described three hypotheses:
(1) the existence of compressive tectonic forces; (2) the volume increase during the
transformation of anhydrite to gypsum; and (3) the crystallization of a gypsum-rich matrix
within the interstitial space between the macro-crystalline gypsum that would provoke
Figure 16.15. Section showing the halite surface crust and the underlying organic-rich mud, Sebkha el
Melah, Zarzis, Tunisia.
399
Figure 16.14. Salinity zones in a playa surface. Cottonball Basin, Death Valley, California (from Hunt
et al. (1966)).
gypsum are the main factors. Secondary gypsum crystals filling the existing pores increase
the volume and the crystallization pressure is responsible for lateral gypsum expansion
and the appearance of dome morphologies. Calaforra (1996) described three hypotheses:
(1) the existence of compressive tectonic forces; (2) the volume increase during the
transformation of anhydrite to gypsum; and (3) the crystallization of a gypsum-rich matrix
within the interstitial space between the macro-crystalline gypsum that would provoke
Figure 16.15. Section showing the halite surface crust and the underlying organic-rich mud, Sebkha el
Melah, Zarzis, Tunisia.