Robertson-Walker cosmologies with a trace anomaly effect in their dynamical description     

Andrzej Woszczyna 《Astrophysics and Space Science》1983,90(1):75-78

The evolution of some vacuum spatially-flat Robertson-Walker universes filled with a massless conformally-invariant quantum field is presented in the energy density-curvature phase plane.  相似文献   

Bulk motion Comptonization in black hole accretion flows     

Andrzej Nied&#;wiecki  Andrzej A. Zdziarski 《Monthly notices of the Royal Astronomical Society》2006,365(2):606-614

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Luminous hot accretion flows: the origin of X-ray emission from Seyfert galaxies and black hole binaries     

Feng Yuan  Andrzej A. Zdziarski 《Monthly notices of the Royal Astronomical Society》2004,354(3):953-960

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Consistency of seven different GNSS global ionospheric mapping techniques during one solar cycle   总被引：1，自引：0，他引：1  

David Roma-Dollase  Manuel Hernández-Pajares  Andrzej Krankowski  Kacper Kotulak  Reza Ghoddousi-Fard  Yunbin Yuan  Zishen Li  Hongping Zhang  Chuang Shi  Cheng Wang  Joachim Feltens  Panagiotis Vergados  Attila Komjathy  Stefan Schaer  Alberto García-Rigo  José M. Gómez-Cama 《Journal of Geodesy》2018,92(6):691-706

In the context of the International GNSS Service (IGS), several IGS Ionosphere Associated Analysis Centers have developed different techniques to provide global ionospheric maps (GIMs) of vertical total electron content (VTEC) since 1998. In this paper we present a comparison of the performances of all the GIMs created in the frame of IGS. Indeed we compare the classical ones (for the ionospheric analysis centers CODE, ESA/ESOC, JPL and UPC) with the new ones (NRCAN, CAS, WHU). To assess the quality of them in fair and completely independent ways, two assessment methods are used: a direct comparison to altimeter data (VTEC-altimeter) and to the difference of slant total electron content (STEC) observed in independent ground reference stations (dSTEC-GPS). The main conclusion of this study, performed during one solar cycle, is the consistency of the results between so many different GIM techniques and implementations.  相似文献   

Planning the Colca Canyon and the Valley of the Volcanoes National Park in South Peru   总被引：1，自引：1，他引：0  

Andrzej Paulo  Andrzej Gałaś  Slávka Gałaś 《Environmental Earth Sciences》2014,71(3):1021-1032

The economic development of the Rio Colca region and related infrastructure endangers the environment of the deepest canyon worldwide. The unique values of the Colca Valley and Canyon and its tributary Valley of the Volcanoes are summarised. They include a magnificent, deep section of the orogenic belt 100 km long, different geological formations, active faults, a variety of fold structures, young volcanoes, hot springs, geysers, several ecological zones and the largest condor habitat in the Andes. Based on the observed land use, development and regional planning, the threats and conflict areas are outlined. Studies performed by the Polish Scientific Expedition to Peru since 2003 add greatly to the knowledge of geology, landscape and pioneering biota development of the area and its importance to the world heritage of nature. They are aimed to give scientific background to the project of the Canyon Colca and Valley of the Volcanoes National Park. The article gives the proposed limits of the park and its buffer zones, categories of protection zones compatible with the SINANPE system of Peru and suggestions on tourist accessibility. The strict protection zone should cover the most inaccessible part of the area where human economic activity practically does not exist. Traditional farming and animal husbandry, wildlife, cultural tourism and some forms of adventure tourism will be allowed in the zone of special usage. The new park would strengthen the relatively poor system of the protected areas in the Arequipa Department, increase tourist attractiveness and determine constraints for sustained regional development. The expected actions of the park authority and local governments are specified.  相似文献   

Protomylonite evolution potentially revealed by the 3D depiction and fractal analysis of chemical data from a feldspar     

Ewa Słaby  Andrzej Domonik  Michał Śmigielski  Katarzyna Majzner  Gediminas Motuza  Jens Götze  Klaus Simon  Izabela Moszumańska  Łukasz Kruszewski  Paweł Rydelek 《Contributions to Mineralogy and Petrology》2014,167(4):1-23

Tourmalinization associated with peraluminous granitic intrusions in metapelitic host-rocks has been widely recorded in the Iberian Peninsula, given the importance of tourmaline as a tracer of granite magma evolution and potential indicator of Sn-W mineralizations. In the Penamacor-Monsanto granite pluton (Central Eastern Portugal, Central Iberian Zone), tourmaline occurs: (1) as accessory phase in two-mica granitic rocks, muscovite-granites and aplites, (2) in quartz (±mica)-tourmaline rocks (tourmalinites) in several exocontact locations, and (3) as a rare detrital phase in contact zone hornfels and metapelitic host-rocks. Electron microprobe and stable isotope (δ¹⁸O, δD, δ¹¹B) data provide clear distinctions between tourmaline populations from these different settings: (a) schorl–oxyschorl tourmalines from granitic rocks have variable foititic component (^X□ = 17–57 %) and Mg/(Mg + Fe) ratios (0.19–0.50 in two-mica granitic rocks, and 0.05–0.19 in the more differentiated muscovite-granite and aplites); granitic tourmalines have constant δ¹⁸O values (12.1 ± 0.1 ‰), with wider-ranging δD (?78.2 ± 4.7 ‰) and δ¹¹B (?10.7 to ?9.0 ‰) values; (b) vein/breccia oxyschorl [Mg/(Mg + Fe) = 0.31–0.44] results from late, B- and Fe-enriched magma-derived fluids and is characterized by δ¹⁸O = 12.4 ‰, δD = ?29.5 ‰, and δ¹¹B = ?9.3 ‰, while replacement tourmalines have more dravitic compositions [Mg/(Mg + Fe) = 0.26–0.64], close to that of detrital tourmaline in the surrounding metapelitic rocks, and yield relatively constant δ¹⁸O values (13.1–13.3 ‰), though wider-ranging δD (?58.5 to ?36.5 ‰) and δ¹¹B (?10.2 to ?8.8 ‰) values; and (c) detrital tourmaline in contact rocks and regional host metasediments is mainly dravite [Mg/(Mg + Fe) = 0.35–0.78] and oxydravite [Mg/(Mg + Fe) = 0.51–0.58], respectively. Boron contents of the granitic rocks are low (<650 ppm) compared to the minimum B contents normally required for tourmaline saturation in granitic melts, implying loss of B and other volatiles to the surrounding host-rocks during the late-magmatic stages. This process was responsible for tourmalinization at the exocontact of the Penamacor-Monsanto pluton, either as direct tourmaline precipitation in cavities and fractures crossing the pluton margin (vein/breccia tourmalinites), or as replacement of mafic minerals (chlorite or biotite) in the host-rocks (replacement tourmalinites) along the exocontact of the granite. Thermometry based on ¹⁸O equilibrium fractionation between tourmaline and fluid indicates that a late, B-enriched magmatic aqueous fluid (av. δ¹⁸O ~12.1 ‰, at ~600 °C) precipitated the vein/breccia tourmaline (δ¹⁸O ~12.4 ‰) at ~500–550 °C, and later interacted with the cooler surrounding host-rocks to produce tourmaline at lower temperatures (400–450 °C), and an average δ¹⁸O ~13.2 ‰, closer to the values for the host-rock. Although B-metasomatism associated with some granitic plutons in the Iberian Peninsula seems to be relatively confined in space, extending integrated studies such as this to a larger number of granitic plutons may afford us a better understanding of Variscan magmatism and related mineralizations.  相似文献   

Deep‐burial alteration of early‐diagenetic carbonate concretions formed in Palaeozoic deep‐marine greywackes and mudstones (Bardo Unit,Sudetes Mountains,Poland)     

Maciej J. Bojanowski  Andrzej Barczuk  Andreas Wetzel 《Sedimentology》2014,61(5):1211-1239

Carbonate concretions formed in bathyal and deeper settings have been studied less frequently than those formed in shallow‐marine deposits. Similarly, concretions affected by catagenetic conditions have rarely been reported. Calcite concretions in deep‐marine mudstones and greywackes of the Bardo Unit (Sudetes Mountains, Poland) formed during early diagenesis and were buried to significant depths. Petrographic and geochemical (elemental and stable C and O isotopic) analyses document their formation close to the sediment–water interface, prior to mechanical compaction within the sulphate reduction zone and their later burial below the oil window. Although the concretions were fully formed during early diagenesis, the effects of increased temperature and interaction with late‐diagenetic interstitial fluids can be discerned. During maximum burial, the concretions underwent thorough recrystallization that caused alteration of fabric and elemental and O isotope composition. The initial finely crystalline cement was replaced by more coarsely crystalline, sheaf‐like, poikilotopic calcite in the concretions. These large calcite crystals engulf and partially replace unstable detrital constituents. The extremely low δ¹⁸O values (down to ?21·2‰ Vienna Pee Dee Belemnite) in the concretions are the result of the increased temperature in combination with alteration of volcanic glass, both causing a significant ¹⁸O‐depletion of bicarbonate dissolved in the interstitial fluids. Recrystallization led to uniform O isotope ratios in the concretions, but did not affect the C isotope signature. The δ¹³C values of the late‐diagenetic cements precipitated in the greywacke and in cracks cutting through concretions imply crystallization in the catagenetic zone and decarboxylation as a source of the bicarbonate. These late‐diagenetic processes took place in a supposedly overpressured setting, as suggested by clastic dykes and hydrofractures that cut through both concretions and host rock. All of these features show how the effects of early and late diagenesis can be distinguished in such rocks.  相似文献   

The Use of Stable Sulfur, Oxygen and Hydrogen Isotope Ratios as Geochemical Tracers of Sulfates in the Podwiśniówka Acid Drainage Area (South-Central Poland)   总被引：1，自引：0，他引：1  

Zdzisław M. Migaszewski  Agnieszka Gałuszka  Artur Michalik  Sabina Dołęgowska  Andrzej Migaszewski  Stanisław Hałas  Andrzej Trembaczowski 《Aquatic Geochemistry》2013,19(4):261-280

The paper presents the results of determinations of stable S and O isotopes of dissolved sulfates and O and H stable isotopes of waters from three ponds, that is, Marczakowe Do?y acid pond, Marczakowe Do?y fish pond and Podwi?niówka acid pit pond, located in the Holy Cross Mountains (south-central Poland). The δ³⁴S_V-CDT and δ¹⁸O_V-SMOW of SO₄ ^2? in waters of three ponds (n = 14) varied from ?16.2 to ?9.5 ‰ (mean of ?13.6 ‰) and from ?8.1 to ?3.2 ‰ (mean of ?4.8 ‰), respectively. The mean δ³⁴S–SO₄ ^2? values were closer to those of pyrite (mean of ?25.4 ‰) and efflorescent sulfate salts (mean of ?25.6 ‰), recorded previously in the Podwi?niówka quarry, than to sulfates derived from other anthropogenic or soil and bedrock sources. The SO₄ ^2? ions formed by bacterially induced pyrite oxidation combined with bacterial (dissimilatory) dissolved sulfate reduction, and presumably with subordinate mineralization of carbon-bonded sulfur compounds, especially in both Marczakowe Do?y ponds. In addition, the comparison of δ¹⁸O–SO₄ ^2? and δ¹⁸O–H₂O values indicated that 75–100 % of sulfate oxygen was derived from water. Due to the largest size, the Podwi?niówka acid pit pond revealed distinct seasonal variations in both δ¹⁸O–H₂O (?9.2 to ?1.6) and δD–H₂O (?29.7 to ?71.3) values. The strong correlation coefficient (r ² = 0.99) was noted between δ¹⁸O–H₂O and δD–H₂O values, which points to atmospheric precipitation as the only source of water. The sediments of both acid ponds display different mineral inventory: the Marczakowe Do?y acid pond sediment consists of schwertmannite and goethite, whereas Podwi?niówka acid pit pond sediment is composed of quartz, illite, chlorite and kaolinite with some admixture of jarosite reflecting a more acidic environment. Geochemical modeling of two acid ponds indicated that the saturation indices of schwertmannite and nanosized ε-Fe₂O₃ (Fe³⁺ oxide polymorph) were closest to thermodynamic equilibrium state with water, varying from ?1.44 to 3.05 and from ?3.42 to 6.04, respectively. This evidence matches well with the obtained mineralogical results.  相似文献   

Sławomir Jerzy (George) Gibowicz (1933–2011)     

Stanisław Lasocki  Andrzej Kijko 《Acta Geophysica》2012,60(1):1-3

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Book Review     

Andrzej Icha 《Pure and Applied Geophysics》2012,169(7):1313-1314

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