A structure of recent morainic sediments, mainly of gravel — boulder fraction (15—60 mm) was studied in the extremely marginal part of the Werenskiold Glacier. The data were collected within three environments of glacial deposition i.e. supraglacial of dead glacial ice and layer of relegation ice adhering to the glacier bottom and subglacial ones. A distinct textural individuality is typical for supraglacial deposits. Arrangement and orientation of boulders coming from the basal part of a glacier as well as from the morainic subglacial sediment deposited under the active ice show many similarities. But in both latter zones as well as certain differentiation was found to be caused by morphology of the older bedrock, changes during a subglacial deposition and preliminary epigenetic changes that occur in the conditions of a subglacial regelation before a stabilization of a passive zone of subglacial permafrost.
A 2.5−metre−long marine core from Isvika bay in Nordaustlandet (80 ° N, 18 ° E) was AMS 14 C dated and analysed for its sedimentological and magnetic parameters. The studied record was found to cover the entire Holocene and indicates major turnovers in the palaeohydrography and sedimentary depositional history. The area was deglaciated at around 11,300 BP. The early Holocene has indications of rapid melting of glaciers and frequent deposition of ice−rafted debris (IRD). The climatic optimum terminated with a probable glacier re−advance event occurring ca. 5800 cal BP. This event caused the deposition of a diamicton unit in Isvika bay, followed by a shift towards a colder and a more stratified hydrographic set − ting. The reduction in IRD indicates gradual cooling, which led to the stratification of the bay and eventually to more persistent fast sea−ice conditions by 2500 cal BP. For the last 500 years, Isvika has again been seasonally open.
Fluted ground moraine deposits in the forefield zones of the Blomli, Scott and Renard glaciers were investigated. It was found that the fluted moraine crests, especially the stone-rich ones, continue on the glacier front surface as cones or stony belts. The linear ablation forms, partly filled by the supraglacial sediment, are the extensions of the crests formed from the finer material. Thus, the opinion is expressed that the ribs and furrows at the top surface of the ground moraine are the result of the supraglacial material deposition and that they reflect the differentation of the ablation relief of the front surface of the recessing glacier. Till now the fluted relief origin was joined exclusively with the subglacial conditions and such forms were considered as the indicators of the glacier movement direction.
Geological investigations of the 4th Polish Geodynamic Expedition to West Antarctica, summer 1990/91, covered the following topics: volcanological studies and mapping at Deception Island; stratigraphic, palaeonotological and sedimentological studies, and mapping of Tertiary glacial and glacio-marine strata on King George Island; sedimentological and mesostructural studies, and mapping at Hurd Peninsula, Livingston Island; and palaeontological sampling of Jurassic (Mount Flora Formation) and Trinity Peninsula Group deposits at Hope Bay, Trinity Peninsula.
Geological investigations of the 3rd Polish Geodynamic Expedition to West Antarctica, 1987—1988, covered the following topics: sedimentological and mesostructural studies of the Trinity Peninsula Group (?Carboniferous — Triassic) at Hope Bay, Cape Legoupil and Andvord Bay, Antarctic Peninsula, and at South Bay. Livingston Island (South Shetland Islands); late Mesozoic plant-bearing terrestrial sediments at Hope Bay; Antarctic Peninsula Volcanic Group, Andean-type plutons and systems of acidic and basic dykes (Upper Cretaceous and ?Tertiary) at Trinity Peninsula and around Gerlache Strait (Arctowski Peninsula, Anvers and Brabant islands); basalts and hyaloclastites within Tertiary glacigenic successions of King George Island; volcanic succession of the Deception Island caldera.
This report describes aims and preliminary results of geological fieldwork carried out by a joint Argentine-Polish party on Seymour (Marambio) and Cockburn islands. Antarctic Peninsula, during austral summer of 1987 88. Seymour Island exposes chiefly shallow-marine, fossiliferous siliciclastic sediments that form an upper, 2000 m thick part in the Mesozoic-Tertiary backarc basin-infill of the Antarctic Peninsula. The fieldwork centered on paleontology and sedimentology of the La Meseta Formation (upper Eocene- ?lower Oligocene), although some observations of older deposits were carried out also. Clupeoid fishes were discovered in the La Meseta Formation. This is the first record of such fish fossils on the Antarctic continent.
GPR method is perfectly suited for recognizing of sedimentary facies diversity in shallowly occurring sediments if there is a contrast of electrical properties between and/or within each layer. The article deals with the issue of the correlation between GPR surveys results and sedimentological analyses. As a result of this correlation a conceptual model of depositional systems of studied areas was developed. Studies were performed in two areas located in central Poland, where glacial deposits formed in the Middle Polish (Saalian) Glaciation are present. The study was based on 49 sediment samples and 21 GPR profiles. Analyses of lithofacies as well as granulometric and mineralogical composition of deposits of collected samples were carried out, showing the diversity of glacial deposits in both study sites. During GPR measurements shielded antenna with a frequency of 500 MHz was used which allowed high-resolution mapping of the internal structure of deposits and to identify four characteristic radar facies. Correlation of GPR profiles with point, one-dimensional sedimentological studies allowed the unambiguous interpretation of the GPR image and draw conclusions about the formation environment of individual units. Geophysical and sedimentological data obtained during study provide a new and detailed insight into selected glacial deposits in central Poland.