Polish Polar Research

Stable isotopes 18O and 13C record of the Kapp Starostin Formation (Late Permian) is presented. The interdependence of δ18O nad δ13C isotope time series is applied for calculating paleotemperatures in the depositional basin of the Kapp Starostin Formation. The obtained results indicate overall cooling from c. 25°—10°C, and confirm some paleogeographical and paleoclimatical inferrences.

Thermoluminescence datings of glacial and marine sediments from Sörkapp Land, southern Spitsbergen enabled to limit the Late and Middle Pleistocene glacial events in this area. Sediments of raised beaches at 15—18, 30—38 and 42—56 m a.s.l. in Breinesflya were TL dated for 63, 68 and 87 ka respectively. Four other dates from Lisbetdalen, Slaklidalen and Sergeijevskardet proved two glacial advances during the Sörkapp Land ( = Wiirm) Glaciation. named the Lisbetdalen Stage (47 and 41 ka) and the Slaklidalen Stage (28 and 22 ka). Glacial sediments on slopes of Gavrilovfjellet and Strupryggen were dated for 141 and 217 ka respectively. These dates prove the glaciers of the Wedel Jarlsberg Land (= Riss) Glaciation occupied a considerably larger area in southern Spitsbergen than the glaciers of the following Sorkapp Land Glaciation.

Three types of rock glaciers (moraine, cirque and subslope ones) were distinguished in northwestern Wedel Jarlsberg Land. Subslope rock glaciers were found different from nival moraines. A development of subslope and fossil cirque rock glaciers was connected with the older Holocene whereas of active cirque and moraine rock glaciers with the Little Ice Age.

Preliminary results of field investigations and analysis of air photos of the Tjörn Valley region (Wedel Jarlsberg Land, Spitsbergen) are presented. The youngest, Quaternary deposits and landforms were mapped. Reconstruction of the last advance and retreat of the Tjörndals Glacier is also described.

The paper presents plant communities from northern Wedel Jarlsberg Land. 55 species of vascular plants were described in this region. Differentiation of plant communities is discussed as controlled by habitat conditions. Plant succession in intramorainal zones of Renardbreen and Scottbreen has been also considered.

Temporal differentiation of the air thermal conditions in SW part of Spitsbergen has been presented in this paper. Daily meteorological records of the Polish Polar Station of the Polish Academy of Sciences in Hornsund have been used for the period of 1978—1986. Distributions of basic thermal indices based on mean, maximum, minimum air temperatures and minimum temperature at a ground surface have been given. Annual patterns of the above elements of various occurrence probabilities have been also presented and thermal periods have been distinguished.

An analysis of observation material concerning fog occurrence in Hornsund collected by seven whole-year expeditions of the Polish Academy of Sciences' to Spitsbergen in 1957—58, 1978—1980, 1981—1985 is presented. The frequencies of fog occurrence in Hornsund during a year and in particular months are compared with respective frequencies calculated for Norwegian stations in Svalbard. Data from the Poland territory are also quoted. The dependences of the fog frequency in Hornsund on air masses advection, circulation type, direction and speed of local winds, time of observation and temperature are shortly analyzed. The periods with long-lasting fogs (exampled by synoptic situations that favor them) are discussed more precisely. A short description of main meteorologie processes favoring the occurrence of fog in this part of Spitsbergen is presented.

Three tectonic units occur in folded stratified volcanic sequence on Barton Peninsula. Fossil flora (Del Valle et al. 1984) occurs in the basal part of the upper unit which age is not younger than Paleocene. The rocks of the middle and lower units are older, possibly Mesozoie.