Segregationseis is a form of ground ice, which is formed by freezing to verlagerndem pore water. It forms well-defined, film-like structures, often it is in the form of ice lenses, which are usually visible to the naked eye. The thickness of the layers may be only a few millimeters or even more than 10 meters. It is found in various types of soil, mineral or organic, preferably is formed in fine-grained, moist ground.
Segregationseis must be distinguished from Injektionseis. The latter is compared to Segregationseis relatively pure and clear. The stratification of segregation ice is in contrast to the injection of ice parallel to the freezing front, which is also evident in the stored soil particles or air bubbles. In practice, however, the distinction is often difficult.
Most Segregationseis formed by frost heave. By a thermodynamic process in which capillary effects also play a role, pore water shifted toward the freezing front - ie usually to the top - and collects in the form of ice lenses. Another type of Segregationseis are reticulated Eisvenen (English: retinculated ice- veins ), which are formed by freezing of pore water as it enters into drying or shrinkage cracks.