Language: English, with trillngual abstract in English, French and German
An attempt has been made to date relic stratified screes deposits at three locations in the Oesling. Because of the absence of contemporaneous floral and faunal remains, an approach primarily based upon the correlation of some phenomena found in these slope deposits with similar ones described and dated elsewhere has been chosen. These phenomena are: a) Included charcoal particles which were dated by radiocarbon analysis. Unfortunately charcoal particles were found only at one site. b) Deformations recognised as cryogenetic which were related to similar phenomena roughly dated in sedimentary areas. c) Included allochthonous heavy-mineral particles of silt sizes which were related to two known and also roughly dated sources supplying them. The data collected suggest that stratified screes accumulations were formed and reworked throughout the Weichselian or Vistulian (ca. 70 000 - ca. 10 000 yr. BP) comprising the Early Glacial, the Pleniglacial and the Late Glacial. Microscopic observations of samples suggest that their packing, a fabric aspect controlling porosity and permeability, is generally rather "loose" ("open work" fabric). This also applies to layers and beds which in the field were regarded as silt-bearing with an ostensible "matrix supported" fabric. Hence, it is inferred that possible occurences of such deposits in the subsurface of the Oesling also today are bound to affect the hydrological behaviour in the catchment areas.