Studia Quaternaria

Within a small (2.5 x 2.5 km) test field, located in the eastern part of the Pomeranian Bay, the geological structure was investigated in detail using seismoacoustic profiling and coring. In the cores, mineral grain size and micro- and macrofauna were analysed. Basing on seismoacoustic records, three main seismostratigraphic units were distinguished. The lowest unit is built of sand and muddy sand. Higher up lies the unit of sandy mud, in some places - of clay. Fauna assemblages indicate cold climate conditions, and clearly point to an existence of lacustrine reservoir of oligotrophic character. Analysis of cores shows that sedimentation began in bog conditions. The lakes in the area existed till the Atlantic period, when due to sea transgression they became filled with sandy sediments. The third unit is built mainly of fine sand, locally medium sand, even with addition of gravel. Basing on the presence of marine fauna, this unit is classified as marine sand.

Alluvial and oxbow deposits preserved 18 m above the Skawa River valley floor are related to the Early Vistulian. Pollen analysis of the two mainly terrestrial profiles revealed a boreal forest succession. The age of the deposits is discussed.

Yezupil is the first Middle Palaeolithic site discovered in upper part of the Dnister River valley. It is situated in a set of sediments composed of loess and fossil soils lying on alluvia. The results of geological and palaeopedological investigations are presented. They contain lithological and geochemical analyses (main components and trace elements), as well as micromorphological study. Palaeo- and petromagnetic record is presented too. Horohiv pedocomplex developed from the older, Wartanian loess. It is composed of luvisol originated during the Eemian Interglacial and chernozem soil - during the Early Vistulian interstadials. An subarctic brown Dubno soil dated to the Interplenivistulian (Middle Vistulian interstadials) separates two parts of the younger loess. Older assemblage of Middle Palaeolithic-Mousterian culture with Levalloisian technique was found in the E horizon of the luvisol and therefore it could be dated to the Eemian Interglacial. Younger Middle Palaeolithic-Micequian- type materials were situated in partially redeposited by solifluction, Early Vistulian chernozem. Scanty and uncharacteristic Upper Palaeolithic assemblage was found in interstadiał Dubno palaeosol

Subfossil trunks of oak (Quercus robur L. and Q. petraea Lieb.) are fundamental for construction of long dendrochronological standards for southern Poland. In the last three years over 400 new oak trunks from alluvial deposits from the basins of the rivers Vistula and Odra were analysed. Most trunks came from the last 2500 years and the produced local chronologies permitted for improvement of the standard chronology POLAND2, covering the period 474 BC-I 555 AD. Subfossil oak trunks from several sites in the river Vistula basin (Grabie, Wolica, Podolsze and others) and from alluvia of the river Odra in Wrocław enabled construction of a new long chronology C_3000E, spanning the years 1795- 612 BC. This chronology was absolutely dated through teleconnection with standards for southern Germany. A row of floating chronologies, dated with the radiocarbon method, was established for the older periods of Holocene. They cover the following intervals: ca. 670-400 BC, ca. 2200-1900 BC, ca. 3400-3100 BC, ca. 3800-3600 BC and ca. 6650-6150 BC. Subfossil oak chronologies constructed by the author, together with standards based on living trees, monuments of wooden architecture, and archaeological timbers from Wielkopolska (449- I 994 AD), Lower Silesia (780-1994 AD) and Małopolska (910-1997 AD) practically allow for absolute dating of oak timbers from the area of southern Poland coming from the last 4000 years.

Lacustrine chalk is very common in post-glacial lakes of northern Poland. In the deposit of Lake Kruk lin (NE Poland) carbonates occur as a layer 2-3 m thick. Samples for laboratory studies were collected from three profiles in SW part of the deposit. Mineral composition of the sediments was determined using differential thermal analysis (DT A) and thermogravimetry analysis (TGA), while the age was determined on the basis of pollen analysis. The sediment profiles represent an age of early Holocene. Calcite is the major component of lacustrine chalk. It forms small crystals (<I O μm), sometimes grouped in aggregates, or present as bioclasts. Calcium carbonate precipitated from lake water. Chemical weathering of glacial and fluvioglacial material of the lake catchment is the main source of ions, transported to the lake mainly by groundwater. Formation of the Kruk lin lacustrine chalk deposit must have required 300-350 kg of dry weight calcium carbonate to be carried away from each square meter of the lake catchment. If only top one-meter layer of glacial sediments had been decalcified, it should have contained 13-22 percent of calcium carbonate. The results of petrographic analysis show this value to be possible.