Ekspedycja międzynarodowa na południową Saharę (cz. II)

Abstract

INTERNATIONAL EXPEDITION TO SOUTHERN SAHARA (PART II) SUMMARY Due to the results obtained during investigations in southern Sahara a lot of problems arise, important for geological sciences (history of craton, periodicity of great climatic changes and glaciations in earth's history, migrations of continents in relation to poles, a.o.). They also throw new light on various sedimentological phenomena (e.g. sedimentation in the zone of a very wide and shallow shelf, transportation of huge masses of terrigenous material at a long distance, a.o.), on glaciological events (development of continental glaciation's within flat and gently elevated areas, glacial deposits a fan ice sheet within the shelf, glacitectonics within valleys cut by leaving glaciers, syngenetical compression of moraines, a.o.), and even on geomorphological phenomena (history of formation of peneplain and of its later sedimentary cover, phases of river system development due to craton movements, a.o.). If possible, these problems will be discussed in the next papers. In addition to the investigations related to the older Palaeozoic, the Sahara expedition enabled the author to observe various processes that develop at present within ,warm desert areas, and to compare these processes with those appearing within cold polar deserts. Of particular interest were also the observations of the present-day changes in Sahara and a comparison of these changes with those from Holocene and Late Pleistocene. The data obtained are valuable mainly as they may serve as comparative materials for the interpretation of geological facts known to occur in Poland, and may contribute to the reconnaissance of the geological phenomena not only of the Quaternary, but also of the older formations.