Sudetes Region Research Articles

Determination of Reservoir Temperatures of Low-Enthalpy Geothermal Systems in the Sudetes (SW Poland) Using Multicomponent Geothermometers

Thermal waters from deep circulation systems are mixed with cold shallow system components during their ascent to drainage zones. In the current research, classic chemical geothermometers and geothermometric modeling using the GeoT app were employed to determine the temperatures of geothermal reservoirs in the Sudetic region. Moreover, models of primary deep components mixed with cold shallow circulation system components were used to determine their proportions, particularly water deposits. In the studied geothermal systems, the proportion of the cold component ranged from c. 46% to c. 75%. Classic cation thermometers (Na-K, Na-K-Ca) indicated a very wide temperature range and they proved rather unreliable. The reservoir temperatures estimated with silica thermometers ranged from 52 °C to 141 °C and they can be deemed more reliable. The temperatures obtained from modeling (54.5 ± 3–120 ± 4) were adopted as temperatures of waters pre-cooled conductively and then mixed with cold components. The temperatures of primary deep waters (74–225 °C) were adopted as geothermal system temperatures.

Accumulation of Arsenic by Plants Growing in the Sites Strongly Contaminated by Historical Mining in the Sudetes Region of Poland.

The uptake of As by various plants growing in highly enriched sites was examined in order to identify potential As accumulators and to assess the risk associated with As presence in plant shoots. Representative samples of 13 plant species, together with soil samples, were collected from various sites affected by historical As mining: mine and slag dumps, tailings and contaminated soils with As concentrations in a range 72–193,000 mg/kg. Potentially and actually soluble As forms, extracted with 0.43 M HNO3 and, 1M NH4NO3 were examined in relation to As concentrations in plant roots and shoots. The latter differed strongly among the species and within them and were in the ranges 2.3–9400 mg/kg and 0.5–509 mg/kg, respectively. The majority (over 66%) of plant samples had As shoot concentrations above 4 mg/kg, an upper safe limit for animal fodder. The uptake of As by plants correlated well with total and extractable soil As, though As concentrations in plants could not be predicted based on soil parameters. Equisetum spp. and C. epigejos indicated a particularly strong accumulation of As in shoots, while A. capillaris, and H. lanatus showed a limited As root-to-shoot transfer, apparently associated with species-related tolerance to As.

Effects of land abandonment and climate change on soil erosion—An example from depopulated agricultural lands in the Sudetes Mts., SW Poland

The aim of the study is to calculate and evaluate the changes in spatial distribution of soil erosion rates related to land use/cover changes and climate changes in the Sudetes Mts. within the last 150years. Various methods were used, including GIS analysis of historical and contemporary land use/cover and climate data, spatial analysis of soil erosion modeling using RUSLE. Changes in spatial distribution of precipitation sums were estimated based on spatial deterministic-stochastic models (regression-kriging) applied to the measurement data from the entire Sudetes region in both analyzed periods.There was a pronounced increase in the area of forests and grasslands at the expenses of arable grounds due to depopulation and consequent land abandonment. These changes started already in the 1880s but they were intensified after World War II. On average soil erosion in the study area decreased by 76.2% (from 4.03tha−1y−1 in the 19th century to present 0.96tha−1y−1). However, the changes in erosion are highly diverse locally in the studied region with the maximum decrease of 8–16tha−1y−1 on steep and higher slopes, which were transformed from arable grounds to forests and grasslands. While both land use and climate changes took place in the study area, changes in land use/cover have a much larger impact on calculated soil erosion rate than climate change. The abandonment of land and the development of spontaneous succession of vegetation limited soil erosion in a very effective way. The values obtained by RUSLE modeling were compared with other values of soil erosion from various field measurements in the Sudetes Mountains in order to evaluate the model. The measurements were based on the experimental plots and sediments stored within the agricultural terraces and in the water reservoirs of various sizes. While the specific sites show large differences in denudation rates, the mean contemporary erosion calculated from our model (0.06mmy−1) corresponds with the average rate of denudation, which was calculated for the entire Sudetes: 0.05–0.01mmy−1 (Jahn 1968).

Ancient DNA and dating of cave bear remains from Niedźwiedzia Cave suggest early appearance of Ursus ingressus in Sudetes

The migration of Ursus ingressus from Southern to Western Europe, where it replaced native forms of Ursus spelaeus, is well documented. However, its occurrence in Central and Eastern European countries is unexplored. We have characterized the cave bear population inhabiting the Sudetes Mountains during the Late Pleistocene. DNA analyses were performed on 39 cave bear specimens from the Niedźwiedzia Cave. Ten successfully yielded the 254-bp sequences of an mtDNA control region. Phylogenetic analyses allowed assignment of nine samples to the U. ingressus haplogroup and one to brown bear (Ursus arctos). The mtDNA haplotypes of U. ingressus formed a single cluster and differed from haplotypes obtained for cave bears from other excavation sites in Europe. Uranium–thorium and radiocarbon dating of selected samples has shown that U. ingressus appeared in the Sudetes region at least 80,000 years ago. This finding may suggest that the appearance of U. ingressus in this area resulted from migration that occurred earlier than the colonization of the Alps and Swabian Jura. It is possible that migration of U. ingressus proceeded along the Carpathian and Sudetes arc.

An assessment of the natural value of selected meadow-pasture communities in the Middle Sudetes region

The paper presents an assessment of the natural values of grassland communities situated in the region of the Middle Sudetes in meso-regions of the Sowie, Kamienne and Walbrzyskie Mountains. The study was carried out in the years 2009–2010 on utilised meadows and pastures. Two hundred and thirty two phytosociological releves were made with the Braun-Blanquet method to estimate phytosociological affiliation of grassland communities. Moreover, species richness and the index of floristic diversity were calculated. Protected species were recorded and their risk categories were estimated. The studies showed that grassland communities belonged to the class MolinioArrhenatheretea. Five phytosociological units in the rank of association or community with the dominating species were distinguished within this class: Arrhenatheretum elatioris, the community Poa pratensis-Festuca rubra, the community with Agrostis capillaris, the association Lolio-Cynosuretum and the community with Alopecurus pratensis. The distinguished grassland communities were characterised by relatively high species richness ranging from 57 species in the community with Alopecurus pratensis to 103 species in the community with Agrostis capillaris and by mean diversity indices H’ ranging from 2.6 to 3.1. In part of analysed grasslands there were 10 strictly or partly protected species. Six of them: Dactylorhiza maculata (L.) Soo, Gymnadenia conopsea (L.) subsp. conopsea R. Br., Trollius europaeus L. s. str. Dactylorhiza majalis (Rchb.) P. F. Hunt & Summerh., Colchicum autumnale L. and Platanthera bifolia (L.) Rich belonged to endangered or rare species in Lower Silesia. The presence of protected and rare species in grasslands increases their natural value. Most valuable phytocoenoses classified as the association Arrhenatheretum elatioris and the community Poa pratensis-Festuca rubra are identifiers of valuable habitats protected within the Natura 2000 system. Obtained results indicate that the studied grassland communities are characterised by a high natural value.

Sedimentary evidence of landscape and climate history since the end of MIS 3 in the Krkonoše Mountains, Czech Republic

A sedimentary core recovered from the cirque basin of Labský důl valley (1039 m a.s.l.) in the Krkonoše Mountains reflects the environmental history for approximately the last 30,000 years. Analyses of magnetic susceptibility, carbon content, pollen assemblages and macrofossil data in a 15 m thick sediment sequence provide the first continuous record of Lateglacial and Holocene vegetation history in Sudetes region of the Czech Republic. The succession of sedimentary units in the lower part of the core suggests that the cirque was ice-free before the onset of the last glaciation at the beginning of marine isotope stage 2. Highly variable climate prevailed during this period with cold conditions culminating about 18 cal ka BP. Cold climates persisted until the Lateglacial period, evidenced by an identified warming and subsequent cooling event correlated with the Younger Dryas period. Sparse, treeless vegetation dominated in the catchment area at that time. The sequence of interrupted thinly laminated silts reflects the retreat and temporary readvance of a local glacier in the cirque during 12.5–10.8 cal ka BP. Subsequently, the alpine treeline ecotone gradually shifted above the cirque floor. Palaeoclimatic conditions in the early Holocene fluctuated strongly, whereas since 5.1 cal ka BP conditions have been more stable. Pollen-based climate reconstructions suggest significant cooling at around 9.8–9.3, 7.7–7.5 and 4.0–3.3 cal ka BP. Spruce forests have dominated the site since 5.0 cal ka BP when the vegetation became similar to the modern one. Two phases of increased sedimentation were identified within the Holocene culminating about 9.2–7.5 cal ka BP and 5.8–5.5 cal ka BP. Sediment yield was as high as 2.4 mm yr −1 during the period, reflecting environmental changes during the Atlantic/Sub-Boreal transition.

Precambrian crustal contribution to the Variscan accretionary prism of the Kaczawa Mountains (Sudetes, SW Poland): evidence from SHRIMP dating of detrital zircons

SHRIMP dating of detrital zircons from sandstones of the Gackowa Formation (Kaczawa Complex, Sudetes, SW Poland) indicates input from late (550–750 Ma) and early Proterozoic to Archaean sources (∼2.0–3.4 Ga, the latter being the oldest recorded age from the Sudetic region). These dates preclude within-terrane derivation from seemingly correlatory acid volcanic rocks of early Palaeozoic age. Rather, they indicate provenance from Cadomian and older rocks that currently form part of other, geographically distant terranes; the most likely source identified to date is the Lusatian Block in the Saxothuringian Zone. Hence, the Gackowa Formation may be late Proterozoic rather than early Palaeozoic in depositional age, possibly coeval with the late Proterozoic (pre-Cadomian) greywackes of Lusatia, being subsequently tectonically interleaved with early Palaeozoic volcanic rocks into the Kaczawa accretionary prism during the Variscan orogeny. However, correlation with the lithologically similar early Ordovician Dubrau Quartzite of Saxothuringia, and so assignation to the early Paleozoic (post-Cadomian) rift succession deposited at the northern margin of Gondwana, cannot yet be precluded.

A drying-upward aeolian system of the Bohdašı́n Formation (Early Triassic), Sudetes of NE Czech Republic: record of seasonality and long-term palaeoclimate change

The record of aeolian processes was studied in Early Triassic sandstones of the upper part of the Bohdašı́n Formation, NE Bohemia, an isolated erosional relict of a Triassic fluvial–aeolian succession in the Sudetes block of the Bohemian Massif (central Europe). The aeolian system exposed in the Devět Křı́žů quarry near Červený Kostelec provides a significant addition to the generally poorly preserved record of Early Triassic palaeoclimate and palaeowind regime in central Europe. Two mutually interbedded facies occur in the aeolian succession: (1) dune facies comprising cross-strata that show interdune, reactivation and superimposition bounding surfaces, and (2) interdune facies, formed by horizontally stratified, commonly mud-draped sandstones, which display a number of indicators of damp to wet conditions and fluctuations in water table. The succession of the Devět Křı́žů Sandstones is interpreted as a record of migration and climb of dunes with intervening interdune flats, which replaced an underlying fluvial system. It is likely that a coeval fluvial system existed near the Devět Křı́žů dune field, providing available sand in dry periods and flooding in wet periods. Dominant palaeowind directions are southwestward and northward in present-day coordinates. Repeated reversals of palaeowind direction, interpreted as seasonal, are recorded in changes in the internal structure of the cross-strata (reworking and reactivation) in the dune migration direction. At least some episodes of dune reworking occurred simultaneously with episodes of water-table rise. A drying-upward trend in the aeolian succession is interpreted from evidence for increased availability of sand through time. The upward transition from a braided fluvial to a wet, drying-upward aeolian system within the Bohdašı́n Formation represents a shift toward maximum aridity of the palaeoenvironment, which marks also the peak arid conditions in the long-term palaeoclimatic evolution of the Carboniferous–Triassic succession of the Sudetes region, and correlates with the establishment of aeolian settings in other regions of central Europe during the Early Triassic. The record of changing palaeowind directions, documented in several cases to have been coupled with episodes of rapid rise in water table, is taken as evidence for pronounced climatic seasonality and brings additional support to the models predicting strong monsoonal circulation during the Early Triassic, affecting particularly the eastern subequatorial coast of Pangaea and adjoining regions.

Eaux minérales et thermales en Pologne

The curative waters used in Polish spas are formed from three main chemical types and their combinations: 1) saline water (sodium chloride) existing in the sedimentary deposits of the Northern Plain and in the Carpathians; 2) carbonated water in the Carpathians and the Sudetes region; 3) water containing hydrasulphides occurring primarily in the foreland of the Carpathians.Various mineral waters are rich in elements such as iodine and bromine which have industrial applications; their extraction could become profitable. The high temperature of certain mineral waters is at the basis of a number of geothermal projects at various stages of advancement.

Geochemistry and tectonic environment of Ordovician meta-igneous rocks in the Rudawy Janowickie Complex, SW Poland

A bimodal suite of Ordovician metavolcanic rocks in the Rudawy Janowickie Mountains and the Lasocki Ridge (Sudetic region, SW Poland) is dominated by voluminous epidote amphibolites and greenschists derived from basalt, dolerite and gabbro precursors. Less abundant felsic components comprise both mylonitized granitic sheets that intrude the mafic rocks, and minor interlaminated volcanic rocks ranging from andesite to rhyolite in composition. These rocks are collectively referred to as the Rudawy Janowickie Complex. In chemical terms the mafic volcanic rocks define three north-south-trending provinces (western, central and eastern) which are separated tectonically by broad major mylonite zones. The western province contains all the alkali basalts in the study area and minor tholeiites, all exhibiting within-plate features: specifically high Zr/Y (>4) and enriched chondrite-normalized incompatible element patterns. The central province contains two fractionated tholeiitic suites (Leszczyniec and Okraj groups) with low Zr/Y ratios (2.0-3.5), depleted to flat REE patterns, and incompatible element compositions ranging from normal MORB to slightly enriched MORB. The eastern province has some features in common with the central province, notably metabasalts with normalized flat REE patterns, although it is also characterized by metagabbro bodies with enriched light REE patterns ((La/Yb) N 4-7), but depleted high field strength element contents. In tectonic terms the Rudawy Janowickie complex is interpreted as a former intracratonic rift floored by oceanic crust and bounded to the west by an attenuated continental margin. Existing data do not allow a definitive conclusion about the exact nature of the eastern margin of the basin: it might, in part reflect the presence of a distant subduction zone.

A Lower Palaeozoic shallow water sequence in the eastern European Variscides (SW Poland): provenance and depositional history

The Gackowa Formation of inferred Cambrian —Ordovician age is part of the metamorphosed pre-Variscan basement of the southern Kaczawa Mountains of the Sudetes region, south-west Poland. Previously variously interpreted as lavas, tuffs and sandstones, it is shown to consist of about 200 m of originally well-sorted siliclastic sedimentary rocks within a sequence of predominantly mafic volcanic rocks. Four facies have been distinguished based on relict sedimentary structures and textures and these suggest that deposition took place on a storm-dominated shelf, mostly above the wave base. The petrography, detrital zircon morphologies and geochemistry suggest affinity with, and derivation in large part from, acid volcanic rocks at a comparable stratigraphic position in a separate tectonostratigraphic unit to the south. The Gackowa Formation and its acid volcanic source rocks have a clear continental geochemical signature, in contrast with the mantle-derived basic/bimodal volcanic rocks below and above; it is suggested that the parent acid magma originated by crustal melting during the ascent of these mantle-derived magmas. A continental crust setting is inferred for the deposition of the Gackowa Formation sandstones, thus suggesting a continental setting for the associated within-plate basalts. The entire volcanic/sedimentary succession resembles elements of the Lower Palaeozoic of Germany, and all may have formed in an initial rift setting during Late Precambrian to Ordovician times.

Polycyclic aromatic hydrocarbons as an indicator of contamination of medicinal waters in the spas in the Sudetes mountains of Southwestern Poland

Thirteen polycyclic aromatic hydrocarbons (PAH) compounds have been identified in spa waters of 10 different health sources in the Sudetes region. In some of the waters the amount of PAH exceed the standard limits set up by the World Health Organization (WHO). The results obtained show that PAH can be a sensitive indicator of pollution of underground water.