Unique Organ Pipes in the Gilf Kebir Crater Field (GKCF) of the Western Desert, Egypt
"Liesegang ring" Phenomenon or Hydro-volcanic Pipes ?

"Liesegang ring" phenomenon

Periodic precipitation or the "Liesegang ring" phenomenon is a special type of chemical pattern formations. It has been discovered by a German chemist, Raphael Eduard Liesegang in 1896 but did not have any general explanation more than a century ago. Several different theories have been proposed to explain the formation of Liesegang rings. To date, however, there is no convincing explanation.
Here are some particularly strange examples in sandstones that are associated with this phenomenon. The idea is that sometime after a sandstone has been deposited, for example, iron-rich surface water or groundwater has formed concentric ringsof consolidation in repeating cycles. These tapes are said to have piled up to pipes due to accumulation, but this has not been proven.

It is only known that there are short horizontally embedded tubes in sandstone of Carboniferous time in Arkansas, which are have been created by the "Liesegang ring" phenomenon.

Hydrovolcanic pipes

The presence of unique pipes in the Abu Ballas region in the Gilf Kebir Crater Field (GKCK), with its countless sub-volcanic structures, speaks for the volcanic origin of this structures.
The walls of the pipes consist of a highly iron-containing quartzitic material. The typical "Liesegang ring" pattern is missing. It is difficult to believe that surface water or groundwater was involved in the formation of these structures. Undoubtedly hot ferrous hydro-volcanic springs formed the pipes to compare with the "black smokers". However, there is evidence that at least the forms of "iron" pipes are also embedded horizontally in the sandstone. This could mean that are lateral tubes from a vertical main hydrotherm, which is hidden in the hills. The lateral pipes are usually hollow or almost completely clogged with "iron".

Vertical main pipes

Horizontal embedded laterally pipes

Other locations:

Jabal Asba (Libya)

South of GKCF-13 (Egypt)

Tassili, Qued Nafeq (Algeria)


Mourdi depression (Chad)


Kysylkum (Uzbekistan)