23 research outputs found

    Constraining long-term denudation and faulting history in intraplate regions by multisystem thermochronology: An example of the Sudetic Marginal Fault (Bohemian Massif, central Europe)

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    The Rychlebské hory Mountain region in the Sudetes (NE Bohemian Massif) provides a natural laboratory for studies of postorogenic landscape evolution. This work reveals both the exhumation history of the region and the paleoactivity along the Sudetic Marginal Fault (SMF) using zircon (U-Th)/He (ZHe), apatite fission track (AFT), and apatite (U-Th)/He (AHe) dating of crystalline basement and postorogenic sedimentary samples. Most significantly, and in direct contradiction of traditional paleogeographic reconstructions, this work has found evidence of a large Cretaceous sea and regional burial (to >6.5 km) of the Carboniferous-Permian basement in the Late Cretaceous (~95–80 Ma). During the burial by sediments of the Bohemian Cretaceous Basin System, the SMF acted as a normal fault as documented by offset ZHe ages across the fault. At 85–70 Ma, the basin was inverted, Cretaceous strata eroded, and basement blocks were exhumed to the near surface at a rate of ~300 m/Ma as evidenced by Late Cretaceous–Paleocene AFT ages and thermal modeling results. There is no appreciable difference in AFT and AHe ages across the fault, suggesting that the SMF acted as a reverse fault during exhumation. In the late Eocene–Oligocene, the basement was locally heated to <70°C by magmatic activity related to opening of the Eger rift system. Neogene or younger thermal activity was not recorded in the thermochronological data, confirming that late Cenozoic uplift and erosion of the basement blocks was limited to less than ∼1.5 km in the study area

    Hydrogeological views and conceptions of Erasmus Sixtus

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    Erasmus Sixtus was a remarkably educated physician, social activist and Lvovian municipal dignitary. His “opus magnum” entitled: “About the Szkło Hot Springs” is a book in which he at large discusses questions of spa medical treatment as well as problems of Szkło spring water origin, movement and quality. Although his considerations are based mainly on concepts of antique and medieval philosophers as well as Renaissance physicians, some ideas concerning groundwater origin, and movement, the causes of its high temperature in case of hot springs, contain rudiments of modern hydrogeological thought

    Changes in phytoplankton of the Southern Baltic in 1979-1988

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    The paper presented contains results of phytoplankton monitoring carried out in the Southern Baltic (Bornholm Basin, Gdańsk and Gotland Deeps) in 1911-1988. No repeated trend in the phytoplankton dynamics over the period of study was observed. A significant increase in abundance of flagellates was characteristic of 1983-1988

    Acoustical techniques of underwater meadow monitoring in the Puck Buy (Southern Baltic Sea)

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    The main motivation of this paper was to develop acoustical techniques to monitor underwater meadows. The data, collected with down-looking echo sounder, were used to develop method of bottom detection and tracking and measurement of vegetation canopy height in the Puck Bay. This method and its accuracy are discussed in details. The other possibilities of recognition between covered and uncovered bottom were also reviewed. The effectiveness of using side scan sonar in study vegetation spatial distribution is demonstrated

    Culturable bacteria community development in postglacial soils of Ecology Glacier, King George Island, Antarctica

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    Glacier forelands are excellent sites in which to study microbial succession because conditions change rapidly in the emerging soil. Development of the bacterial community was studied along two transects on lateral moraines of Ecology Glacier, King George Island, by culture-dependent and culture-independent approaches (denaturating gradient gel electrophoresis, DGGE). Environmental conditions such as cryoturbation and soil composition affected both abundance and phylogenetic diversity of bacterial communities. Microbiocenosis structure along transect 1(severe cryoturbation) differed markedly from that along transect 2 (minor cryoturbation). Soil physical and chemical factors changed along the chronosequence (time since exposure) and influenced the taxonomic diversity of cultivated bacteria (CB), particularly along transect 2. Arthrobacter spp. played a pioneer role, and were present in all soil samples, but were most abundant along transect 1. Cultivated bacteria isolated from transect 2 were taxonomically more diverse than those cultivated from transect 1; those from transect 1 tended to express a broader range of enzyme and assimilation activities. Our data suggest that cryoturbation is a major factor in controlling bacterial community development in postglacial soils, shed light on microbial succession in glacier forelands, and add a new parameter to models that describe succession phenomena
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