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1

Effects of steaming on tensile stress development and check risk during kiln-drying of European beech (Fagus sylvatica L.) wood

100%

Majka J.

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tom 39

2

Ditlenek siarki

63%

Majka J. , Rolecki R.

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tom Nr 18

67--104

3

Pressure-temperature estimates on blueschists from the Vestgötabreen complex (Western Svalbard)

51%

Kośmińska K. , Majka J. , Manecki M. , Kozub G. A.

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tom Vol. 40, no. 1

94--95

EN

In Oscar II Land (Motalafjella area, western Svalbard), an exotic high-pressure (HP) metamorphic unit, namely the Vestgötabreen Complex (Kanat & Morris 1988) occurs. It is thrust over low-grade metasediments (e.g. Labrousse et al. 2008) of inferred Neoproterozoic age. This complex is subdivided into the Lower (LU) and Upper Unit (UU) differing from each other in terms of lithologies and pressure-temperature (P-T) conditions. The LU is composed of high pressure-low temperature (HP-LT) metasediments with minor intercalations of blueschists, whereas the UU comprises metasediments, more voluminous blueschists and scattered lenses of eclogites. Radiometrie dating yield the age of c. 470 Ma for the HP metamorphism in the Motalafjella region (Horsfield 1972, Dallmeyer et al. 1990, Bernard-Griffiths et al. 1993). The P-T conditions for carpholite-bearing schists from the LU yield the pressures up to c. 16 kbar and temperatures in the range of 330-450°C (Agard et al. 2005), whereas eclogites from the UU were subjected to 18-24 kbar pressure and temperatures of 580-640°C (Hirajima et al. 1988). The aim of this study is to decipher meta-morphic evolution of blueschists using thermodynamic phase equilibrium modeling. Samples have been collected from the UU, cropping out at the Skipperryggen ridge. They contain mostly garnet, glaucophane, phengite, rutile and chlorite. Additionally lawsonite, ilmenite and epidote can be found in minor amounts. Garnet typically forms euhedral to subhedral porphyroblasts. It contains voluminous inclusions of white mica, epidote, rutile and amphibole. Garnet shows chemical compositional variation from Alm63Prp19Grs22Sps2 in the cores to Alm60Prp19Grs20Sps1 in the rims. The pyrope zoning is bowl-shaped, whereas grossular and spessartine profiles show bell-shaped trends. The almandine content is generally constant through the grain. The P-T conditions were estimated using the phase equilibrium modeling in the NCKFMASHTO system using the Perple_X software (Connolly 2005). Modeling was based on bulk-rock chemistry as well as garnet and phengite compositional isopleths. P-T estimates indicate peak conditions of ca. 20 kbar and 520°C. These estimates for studied blueschists from Skipperryggen are in agreement with previous studies on the Vestgötabreen Complex. Also, recent studies in Nordenskiöld Land (south of Oscar II Land) revealed the occurrence of blueschist facies rocks. These blueschists yielded similar P-T conditions to blueschists from the Vestgötabreen Complex (18 kbar, 470°C; Kośmińska et al., in press). More regionally, all aforementioned HP-LT lithologies may be correlated with the ophiolitic sequence occurring within the Pearya Terrane of northern Ellesmere Island (e.g. Labrousse et al. 2008, Kośmińska et al., in press). Detailed tectonic, petrological and geochronological studies are in progress.

4

Metavolcanics of Nordenskiold Land from SW Svalbard as an example of New Ocean Crust

45%

Gołuchowska K. , Barker A. K. , Manecki M. , Majka J. , Czerny J.

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tom Vol. 38, no. 4

473

EN

This study concerns late Neoproterozoic metavolcanics from southwestern Svalbard in an investigation to trace the evolution of oceans plate rifting. A number of outcrops of these rocks are connected with the regional Torellian unconformity, which is associated with a Late Neoproterozoic orogenesis event - post 640 Ma. This unconformity divides the younger metasediments of the Sofiebogen Group from older metasedimentary sequence of the Deilegga Group. Samples have been collected from Nordenskiold Land belonging to the Sofiebogen Group, which is situated between Bellsund and Isfjorden, to the north of Wedel Jarlsberg Land. Field observation reveals that these metavolcanics very often occur as a pillow lavas and lavas. They contain mineral assemblages typical for greenschist facies metamorphism such as: actinolite, chlorite, epidote, albite, but some of them contain garnets and glaucophane, which is typical for blueschist facies conditions. Based on a total alkali silica diagram they are classified as tholeitic basalts. Spider diagram shows patterns similar to MORB, where the REE are flat. The LILE except Sr are depleted, but this depletion is caused probably by metamorphism. However, the metavolcanics of Nordenskiold Land are also relative depleted in HFSE (Th/Yb = 0.2-0.31 and Nb/Yb = 2.9-4.4) and LREE (Lan/Smn = 1.0-1.5). Trace elements like Nd, Th, Yb and La show trends that could be associated with fractional crystallization. The geochemical character of metavolcanics from Nordenskiold Land, as well as, their forms (pillow lavas) suggests that they created beneath the sea level, as new ocean crust.

5

Role of curcumin in protection of gastric mucosa against stress-induced gastric mucosal damage. Involvement of hypoacidity, vasoactive mediators and sensory neuropeptides

32%

Czekaj R. , Majka J. , Ptak-Bielowska A. , Szlachcic A. , Targosz A. , Magierowska K. , Strzalka M. , Magierowski M. , Brzozowski T.

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nr 2

6

Welcome in Herlandia 2013 XIV International Conference of Young Geologists Herl'any 2013 Svaty Jur, Slovak Republic; 4-6 April 2013

32%

Zahradnikova B. , Greganova M. , Zahradnik L. , Kovacova M. , Strba L. , Vizi L. , Majka J. , Dwornik M. , Bazarnik J.

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tom Vol. 38, no. 4

451--452

EN

The XIV International conference of young geologists was organized in Svaty Jur near Bratislava from 4 to 6 April 2013. Conference was traditionally organised by members of Geological Club in Bratislava and by team from AGH University of Sciences and Technology in Krakow and Faculty BERG of Technical University in Kosice. Scientific guarantee of the conference this year took over Prof. Dusan Plasienka from Faculty of Natural Sciences, Comenius University in Bratislava (SK), Prof. Maciej Manecki from AGH, University of Sciences and Technology in Krakow (PL) and Dr. Julian Kondela from Faculty BERG of Technical University in Kosice (SR).