Episodes of extreme rainwater pollution and its relationship with synoptic situation (Wielkopolski National Park,Poland)

Synoptic conditions of extreme rainwater pollution episodes, evidenced by maximum values of parameters measured in the protected area of Wielkopolski National Park (western-central Poland), were analysed in this study. Precipitation samples were tested for the following parameters: pH, electrical conductivity and the concentration of the following elements: F^-, Cl^-, NO₂^-, NO₃^-, PO₄^3-, SO₄^2- and Na⁺, NH₄⁺, K⁺, Mg²⁺, Ca²⁺. It was assumed, that in winter, western advection of Atlantic air masses was the most frequent aerosol and pollution transport scenario for the investigated area. In summer the most heavily pollution occur at the intensified meridional flow over the central Europe, indicating advection of cooler air from northern Europe and the North Sea. In most of cases, the weather conditions causing extreme concentration of examined pollutants, were determined by the movement of weather fronts over considerable parts of Poland and by precipitation caused by those fronts.     

Organic matter from the Callovian (Middle Jurassic) deposits of Lithuania: Compositions,sources and depositional environments

This study presents the first organic geochemical and petrographical investigation of the Callovian deposits of the eastern part of the Central European Basin. It is shown that in both the terrigenous Papil? Formation (Lower Callovian) and shallow- to deeper-marine facies of the Papartin? and Skinija formations (Middle and Upper Callovian, respectively), terrestrial organic matter predominates. This is reflected by the carbon preference index values higher than 1.2 for all samples and in some cases higher than 2, as well as the occurrence of characteristic higher plant biomarkers like cadalene, dehydroabietane, simonellite and retene. Moreover, in the case of the Papil? Formation, sugiol – a natural product terpenoid produced by distinct conifer families, has been detected in clay sediments. The occurrence of such a biomolecule in the Middle Jurassic clays is reported for the first time. Its occurrence is probably connected with the presence of small wood debris in the clay sediments. In samples of the Papil? Formation, charcoal fragments co-occurring with unsubstituted polycyclic aromatic hydrocarbons were detected, indicating that wildfires took place during the Early Callovian of Lithuania and/or neighbouring areas. In the Middle and Upper marine Callovian sediments of Lithuania there is no evidence of anoxic conditions occurring in the water column. However, periodic anoxic or strongly dysoxic episodes may have occurred, most probably below the photic zone, during the deepest phase of the Late Callovian transgression, as is evidenced from pyrite framboid diameter distribution and general impoverishment of benthic fauna. Huminite reflectance (R_r) values for the investigated area are in the range of 0.21–0.31%, suggesting the occurrence of immature organic matter. Such values indicate that these investigated deposits were close to the surface during their whole diagenetic history, and the thickness of younger cover did not exceed ca. 500 m. This is also supported by a biomarker analysis in which less thermally stable ββ-hopanes and hopenes significantly dominated.     

Thermo-mechanical facies representative of fast and slow flowing ice sheets: the Weichselian ice sheet,a central west Poland case study

This study deals with an issue of thermo-mechanical facies, reflecting specific thermal and mechanical properties of the subglacial environment. The main objective of this study was to develop a model of glacitectionic deformation and its sedimentary record beneath fast and slow flowing ice sheets, based on investigations conducted in Wielkopolska (west central Poland). Sedimentary structures, mainly at the contact between subglacial tills and glacifluvial sediments, were recognized to delineate typical facies associations in a Weichselian glacigenic succession. Each association was interpreted as a record of the different depositional environments related to different subglacial conditions. Those investigations suggest the substratum was composed of frozen and dry, and wet and mobile spots, and four thermo-mechanical facies were distinguished: A – is representative of slower ice flow, dry and cold subglacial conditions, where driving stresses and normal effective pressure were high; B – is also related to slow ice flow and occurrence of cold subglacial permafrost, but with little amount of unfrozen water (however, higher than in facies A), with similar physical characteristics of the ice sheet as facies A; thermo-mechanical facies C and D represent wet and warm ice sole, with low normal effective pressure and driving stresses, thus lowering sediments’ shear strength and enabling high ice-flow velocities. We suggest that these facies have specific and non-random location, thereby revealing the relationship between subglacial thermo-mechanical conditions and ice sheet dynamics. Slow moving, cold-based ice occurred along ice sheet margins and inter-stream areas, whereas fast-moving, warm-based, well-lubricated ice, was typical of the axial parts of ice streams.     

Long‐distance fluid migration defines the diagenetic history of unique Ediacaran sediments in the East European Craton

The diagenetic history of the Ediacaran sedimentary rocks in the East European Craton (EEC) over the area extending from Arkhangelsk (Russia) in the north to Podolia (Ukraine) in the south was revealed by means of the XRD characterization and K–Ar dating of clay fractions, mudstone porosity measurements and organic geochemistry investigations. Mudstone porosity measurements produced direct evidence of shallow maximum burial of the Ediacaran sediments on the craton (Russia, Lithuania, Belarus, Volyn), not exceeding 1.5 km, and much deeper burial at the cratonic margin, in Podolia and Poland. In general, illitization of smectite and biomarker indices indicates more advanced diagenesis at the cratonic margin. K–Ar dating of authigenic illite–smectite and aluminoceladonite revealed the Palaeozoic age of mineral diagenesis (ca. 450–300 Ma) both on the craton and its margin, with older ages generally observed in the north. When the maximum palaeotemperatures were evaluated from illite–smectite and biomarkers, based on the calibrations from the conventional burial diagenetic sections, a major mismatch was detected for the cratonic area: 100°C–130°C from illite––smectite and tens of ^oC lower from the lipid biomarkers. This diagenetic pattern was interpreted as the result of short‐lasting (in ky scale) pulses of potassium‐bearing hot fluids migrating from the Caledonian and Variscan orogens deep in the craton interior, effectively promoting illitization in porous rocks without altering the organic matter. Analogous short pulses of fluids were responsible for numerous diagenetic phenomena, including Mississippi Valley‐Type ore deposits, in the American Midwest, in front of the Appalachians. K–Ar dating indicates that the entire Proterozoic sedimentary cover of the Great Unconformity on the EEC remained untouched by measureable post‐sedimentary changes until the early Palaeozoic, thus for over 1000 My, which is an unprecedented finding.     

Characteristics of high-mountain karst based on GIS and Remote Sensing

Spatial data were used to develop complex characteristics of a high-mountain karst. The numeric elaboration was conducted using the analytical capabilities of GIS software. Analysis was based on spatial data gained by elaborating aerial photography. The results were presented in map sets, as well as Geographic Information System format. The set of matched numerical methods used and the proposed algorithm for data analysis may be applied at other karst sites.