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1.
In the southern Pannonian Basin, the Variscan Barrovian- and overprinted Abukuma-type progressive metamorphic sequences of the South Tisia in Slavonian Mts. (SM) and Mt. Moslava)ka Gora (MG) are interlayered with orthoamphibolites. These sequences represent part of a disrupted Variscan belt that extends southeastwards of the Bohemian Massif through the Carpathians to the Caucasus. Orthoamphibolites contain hornblende (Mg-hornblende, tschermakite, pargasite, and edenite), plagioclase An48-98 (MG) and An26-35 (SM), biotite, grossular (MG) and almandine (SM) enriched garnet, diopside (MG), with accessory ilmenite, titanite, and clinozoisite. Based on major and trace element analyses and CIPW norms, these orthoamphibolites, which originally were olivine tholeiites to slightly alkalic basalts, can be correlated with tholeiites of consuming plate margins. '18O of orthoamphibolites varies from 5.8 to 7.1, the measured 87Sr/86Sr ratio from 0.70435 to 0.70665, which indicates slight continental crust contamination, and the calculated ratio from 0.70262 to 0.70535, indicating an upper mantle origin of the original basaltic melts. For associated penecontemporaneous I-type granitoids, the calculated initial 87Sr/86Sr ratio also have upper mantle values ranging between 0.70293 and 0.70368. Geochemical data for orthoamphibolites and the associated penecontemporaneous I-type granites, and the occurrence of alpine-type ultramafic bodies within the Barrovian sequence, indicate that they have many features in common with orogenic associations related to recent subduction-related settings. Some characteristic element ratios suggest back-arc basin environments and the Ce/K vs. Ce diagram suggests a pargasite-lherzolite source. Its partial melting gave primitive basaltic melts of olivine tholeiite to slight alkalic affinities that produced at first differentiated mafic rocks by olivine fractionation (future orthoamphibolites) and, afterwards, a strongly differentiated suite of I-type granitoids by amphibole fractionation. Magma emplacement and subsequent AFC processes took place in subduction environments preceding the main Variscan deformational metamorphic event during which orthoamphibolites were generated. This interpretation is compatible with geodynamic modeling of this part of the Paleotethys. 相似文献
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Within a wide range of best management practices for stormwater management in urban areas, there has been an increasing interest in source control measures. Source controls such as low-impact development (LID) techniques are potentially attractive as retrofit options for older developed areas that lack available land to implement conventional measures such as stormwater management ponds. Hence, distributed urban drainage models requiring detailed representation of developed drainage areas should be developed to accurately estimate the benefits that LIDs may provide. This study (1) presents a two-stage classification process on a high-resolution WorldView-2 image, and (2) demonstrates how to use the extracted land cover information in the subsequent hydrologic modelling and assessment of different LIDs’ performance. The proposed two-stage classification method achieved an overall accuracy of 80.6%, whereas a traditional pixel-based achieved 68.4% in classifying the same urban area into six land cover classes. From the classification results, the hydrologic properties of micro-subcatchments were imported in the United States Environmental Protection Agency Storm Water Management Model to assess the performance of LIDs. A reduction of run-off volume 18.2% and 37.1% was found with the implementation of porous pavement and bioretention, respectively, in a typical low-rise residential area located in the city of San Clemente, California, US. The study demonstrates the use of high-resolution remote sensing image to aid in evaluating LID retrofit options, and thus benefits in situations where detailed drainage area information is not available. 相似文献
4.
Dragutin T. Mihailovic Jelena Lazic Jacek Leśny Janusz Olejnik Branislava Lalic Darko Kapor Ana Cirisan 《Theoretical and Applied Climatology》2010,100(3-4):299-323
Numerical simulations and tests with the recently redesigned land–air parameterization scheme (LAPS) are presented. In all experiments, supported either by one-point micrometeorological, 1D or 3D simulations, the attention has been directed to: (1) comparison of simulation outputs, expressing the energy transfer over and through heterogeneous and non-heterogeneous surfaces, versus observations and (2) analysis of uncertainties occurring in the solution of the energy balance equation at the land–air interface. To check the proposed method for aggregation of albedo, “propagating hole” sensitivity tests with LAPS over a sandstone rock grid cell have been performed with the forcing meteorological data for July 17, 1999 in Baxter site, Philadelphia (USA). Micrometeorological and biophysical measurements from the surface experiments conducted over crops and apple orchard in Serbia, Poland, Austria and France were used to test the operation of LAPS in calculating surface fluxes and canopy environment temperatures within and above plant covers of different densities. In addition, sensitivity tests with single canopy covers over the Central Europe region and comparison against the observations taken from SYNOP data using 3D simulations were made. Validation of LAPS performances over a solid surface has been done by comparison of 2 m air temperature observations against 5-day simulations over the Sahara Desert rocky ground using 3D model. To examine how realistically the LAPS simulates surface processes over a heterogeneous surface, we compared the air temperature measured at 2 m and that predicted by the 1D model with the LAPS as the surface scheme. Finally, the scheme behaviour over urban surface was tested by runs over different parts of a hypothetical urban area. The corresponding 1D simulations were carried out with an imposed meteorological dataset collected during HAPEX-MOBILHY experiment at Caumont (France). The quantities predicted by the LAPS compare well with the observations and the various subcomponents of the scheme appear to operate realistically. 相似文献
5.
Josip Mesec Darko Vrkljan Zvonimir Ester 《Geotechnical and Geological Engineering》2009,27(3):431-438
This paper analyses results of trial, construction and quarry blasting, carried out in sediment rock deposits, mainly limestone
and dolomite. Based on results of seismic measurements and engineering geological observations in sedimentary formation, an
empirical relationship was established between ground vibration and geological strength index (GSI). The charge weight of explosive that may be detonated per delay for any given distance of nearby structures from the blast
is approximately determined by using the concept of the scaled distance (SD) along with the DIN 4150 standard. 相似文献
6.
Stanislav Frančišković-Bilinski Mladen Juračić Darko Tibljaš 《Environmental Earth Sciences》2011,64(7):1755-1761
Surface sediments (fraction <63 μm) from the source to the mouth of the Rječina, short (18.3 km) karst allogenic river in
Croatia, which is an important source of drinking water, were studied to investigate their mineral (by XRD) and chemical (by
ICP-MS) composition to check possible anthropogenic influence at the lower course due to paper industry and mills, and in
the prodelta area from untreated municipal sewage and the large harbor of Rijeka town. In all analyzed sediment samples and
in the sandstone source, rock quartz is a major mineral, while feldspar and mica group minerals are less abundant. Chlorite
is a minor or trace mineral in all samples. Calcite and dolomite are abundant in the river prodelta, reflecting changes in
bedrock lithology from flysch to carbonates. In river sediments, Fe is the most abundantly analyzed element, while Ca is the
most abundant in prodelta sediments. Concentrations of Al, Mn, Ni, Cr, Co, La and Nd decrease downstream, while Mg, S, Na,
B, Pb, Zn, As, Sn, U, Mo, Hg and Ag have relatively higher concentration in prodelta sediments. The results are compared with
sediments of other rivers in the area: Raša, Rižana and Dragonja, as well as with those of the Rosandra Creek (Italy). Sediments
in the Raša River showed similar behavior as those in the Rječina, as the highest concentration of metals was found in the
restricted upper part of the estuary, characterized by rapid deposition of clay particles and terrestrial sedimentary organic
matter. The comparison also showed that the most contaminated were the sediments from the Rižana, followed by those from the
Rječina and Rosandra Creek, which had similar results. Among the studied elements, As was present in all sediment samples
at concentrations >6 ppm that might have the lowest toxic effects. At the lower Rječina and in prodelta sediments, Pb was
also present at slightly elevated concentrations (>31 ppm) that could cause such effects. Concentrations of Zn in the prodelta
correspond to those occurring in moderately polluted sediments (90–200 ppm). In the prodelta sediments, Hg is slightly below
toxicity threshold (1 ppm), while Ag is present at toxicity threshold (0.5 ppm) or close to it. Rječina River could act as
a good illustrative example for behavior of toxic metals in allogenic karstic rivers, in which accumulation of anthropogenically
introduced pollutants usually occurs in their estuaries, as a result of transport and deposition of fine particles. 相似文献
7.
Edward D. Goldberg Minoru Koide Kathe Bertine Vern Hodge Martha Stallard Darko Martincic Nevenka Mikac Marco Branica Jamal K. Abaychi 《Applied Geochemistry》1988,3(6)
Inorganic surfaces sorb dissolved and particulate phases from seawater onto organic films from a variety of sources. Heavy metals such as Au, Pt, Mn and Cd come to the coatings primarily from particulate phases. This observation confirms a previous finding of this laboratory for the uptake of U, Pu and Po. With depth in the open ocean there are greater contributions from the dissolved phases. Microbial and photochemical processes can enrich surfaces in some metals through reduction reactions. Copper and Mn enrichments in the films are attributed to the photo-reductions of Cu(II) to Cu(I) and manganese oxides to Mn(II), respectively, while the uptake of Mo is a consequence of the reduction, mediated by organisms, of molybdate to Mo(V) or Mo(IV). Cadmium, on the other hand, appears to be bioaccumulated in the films. 相似文献
8.
Listric versus planar normal fault geometry: an example from the Eisenstadt-Sopron Basin (E Austria) 总被引：1，自引：0，他引：1
Darko Spahić Ulrike Exner Michael Behm Bernhard Grasemann Alexander Haring Herbert Pretsch 《International Journal of Earth Sciences》2011,100(7):1685-1695
In a gravel pit at the eastern margin of the Eisenstadt-Sopron Basin, a satellite of Vienna Basin (Austria), Neogene sediments
are exposed in the hanging wall of a major normal fault. The anticlinal structure and associated conjugated secondary normal
faults were previously interpreted as a rollover anticline above a listric normal fault. The spatial orientation and distribution
of sedimentary horizons and crosscutting faults were mapped in detail on a laser scan of the outcrop wall. Subsequently, in
order to assess the 3D distribution and geometry of this fault system, a series of parallel ground penetrating radar (GPR)
profiles were recorded behind the outcrop wall. Both outcrop and GPR data were compiled in a 3D structural model, providing
the basis for a kinematic reconstruction of the fault plane using balanced cross-section techniques. However, the kinematic
reconstruction results in a geologically meaningless normal fault cutting down- and up-section. Additionally, no evidence
for a weak layer serving as ductile detachment horizon (i.e. salt or clay horizon) can be identified in stratigraphic profiles.
Instead, the observed deflection of stratigraphic horizons may be caused by a displacement gradient along a planar master
fault, with a maximum displacement in the fault centre, decreasing towards the fault tips. Accordingly, the observed deflection
of markers in the hanging wall—and in a nearby location in the footwall of the normal fault—is interpreted as large-scale
fault drag along a planar fault that records a displacement gradient, instead of a rollover anticline related to a listric
fault. 相似文献
9.
Stanislav Frančišković-Bilinski Robert Scholger Halka Bilinski Darko Tibljaš 《Environmental Earth Sciences》2014,72(10):3939-3953
The aim of the present work was to investigate links between the low-field magnetic susceptibility (MS) and chemical and mineral composition of sediments from several Croatian and Slovenian rivers, as well as to determine possible anthropogenic influence on these sediments. MS measurements are a fast and simple method, which serves as a proxy for the estimation of pollution in different environmental systems. The investigated rivers are predominantly unpolluted rivers from Croatian and Slovenian karstic and flysch areas, which belong to the Adriatic or the Black Sea watersheds: the Dragonja, the Mirna, the Ra?a, the Ri?ana, the Reka, the Rak, the Cerkni?nica, the Unec and the Ljubljanica rivers. It was assumed that, due to their mostly unpolluted status, they could serve as a database for natural MS background values for this region. For comparison, several rivers and a lake from the Celje old metallurgic industrial area (Slovenia) were also investigated: the Savinja, the Hudinja, the Voglajna rivers and Slivni?ko Lake. They form a sub-basin of the Sava River drainage basin. Sediments of the clean karstic and flysch rivers showed extremely low MS values, with mass susceptibility values ranging from 0.58 × 10?7 to 5.11 × 10?7 m3/kg, and isothermal remanent magnetism (IRM) values ranging from 0.71 to 7.88 A/m. In the Celje industrial area, river sediments showed much higher MS values, with mass susceptibility values ranging from 1.31 × 10?7 to 38.3 × 10?7 m3/kg, and IRM values ranging from 0.91 to 100.42 A/m. The highest MS value was found in the Voglajna River at Teharje-?tore, a point which showed a significant number of anomalies of toxic metals in earlier investigations. Semiquantitative determination of relations between grain size and concentration of magnetite was performed using the Thompson-Oldfield method. X-ray diffraction (XRD) mineralogical analysis showed that sediments of the Celje area have mostly quartz as major mineral, with relatively small amount of carbonate minerals, while in sediments of karstic rivers carbonate minerals prevail. Statistically significant correlations were obtained between MS and Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Ba in the Slovenian karstic region and between MS and Cr, Fe, Co, Ni and Zn in flysch drainage basins. On the contrary, no correlation of MS and Hg content was obtained. 相似文献
10.
Natural and artificial radioactivity distribution in soil, rock and water of the Central Ashanti Gold Mine, Ghana 总被引：1，自引：1，他引：0
A. Faanu D. O. Kpeglo M. Sackey E. O. Darko G. Emi-Reynolds H. Lawluvi R. Awudu O. K. Adukpo C. Kansaana I. D. Ali B. Agyeman L. Agyeman R. Kpodzro 《Environmental Earth Sciences》2013,70(4):1593-1604
Direct gamma spectrometry study was carried out within and around the operational area of the Central Ashanti Gold of Ghana to ascertain the baseline radioactivity levels of naturally occurring radioactive materials (NORM), prior to processing of gold ore at the mine. The average activity concentrations of 238U, 232Th, 40K and 137Cs in the soil/rock samples were 64.3, 68.4, 1243.9 and 3.5 Bqkg?1, respectively. For the water samples, the average activity concentrations were 2.5, 2.6, 14.7 and 0.7 BqL?1 for 238U, 232Th, 40K and 137Cs, respectively. The total annual effective dose to the public was estimated to be 0.141 mSv which is below the ICRP recommended level of 1 mSv for public exposure control. The average radium equivalent activity value was 257.8 Bqkg?1 in the range of 72.9–402.3 Bqkg?1. The average values of external and internal indices were 0.7 and 0.8, respectively. The concentrations of U, Th and K were variable in soil and rock samples taken from different locations in the study area with values varying in the range of 0.8–10.9, 2.4–39.4 μg/g and 0.7–6.3 %, respectively. The concentration values of gross-α and gross-β for all the water samples were below the Ghana Standards Board and Who Health Organisation recommended guideline values for drinking water quality. The results obtained in this study shows that radiation levels are within the natural background radiation levels found in literature and compared well with similar studies for other countries. 相似文献