Teepee Structure
The fold appearing in these sediments along the shores of the Dead Sea is known as a teepee structure. It’s found freshly-formed here, but similar structures are found in rocks going back billions of years. They are often found in tidal flat and evaporate-rich settings, like one sees today at the shores of the Dead Sea.
This environment gives some idea of how the structure forms. A teepee like this is created when minerals keep growing inside of a layer, as can happen for example when groundwater moves up and down. Each time the water moves out of the layer, the layer dries out and slightly more salt is precipitated. Eventually the layer runs out of room for more salt, but the minerals can still keep growing, creating a compression force within the layer.
That force then lifts the layer up into a tight, teepee-shaped fold, creating this structure.
The migration of water in and out with tides or up and down during wet and dry seasons is key to creating these cycles of mineral growth and creating the pressure it takes for these to develop, so when these are found in the geologic record, it is an indication that the rocks were deposited in a setting near a shoreline.
-JBB
Image credit: http://en.wikipedia.org/wiki/Sedimentary_structures#mediaviewer/File:Halite_Teepee_structure_Dead_Sea_031712.JPG
Read more: http://woostergeologists.scotblogs.wooster.edu/2012/03/17/wooster-geologists-in-an-extraordinary-world-of-salt/ http://books.google.com/books?id=Yebzay3a0FwC&lpg=PA131&ots=T1DClJ9r-K&dq=teepee+structure+sedimentary&pg=PA131#v=onepage&q=teepee%20structure%20sedimentary&f=false
