The oldest periglacial period in the Poland

Abstract

One of the debated problems in Poland concerns the so-called preglacial formation. It consists of pebbles, gravels, sands, and dusty deposits situated at the boundary between the Tertiary and the Quaternary. The lack of fauna and Scandinavian erratic rocks does not allow the exact age of this formation to be determined. The author analyzed the formations in question in several sections of the Lublin Plateau and Lower Silesia. He found traces of periglacial structures (solifluction), as well as evidence of intense frost weathering and a certain rhythmicity of stratification. These features provide proof of climatic changes contemporaneous with the time of deposition of the studied formation. Finally, within the mass of this formation, we have observed clearly visible traces of intense aeolian erosion. The author tends to conclude that the so-called preglacial formations in Poland are not all of the same age. Some originate from the boundary between the Tertiary and the Quaternary, while others, especially in southern Poland, should be linked to the earliest glaciation. All these formations are attributable to a climate that was certainly dry and probably cold, particularly in the case of the detrital formations in the Sudetes.