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Number of results: 11
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Abstract

Adamussium jonkersi sp. nov. is described from the Late Oligocene Destruction Bay Formation, Wrona Buttress area, King George Island (South Shetlands), West Antarctica. The unit, characterized by volcanic sandstone, is a shallow marine succession deposited in a moderate- to high-energy environment. The thin-shelled pectinids, collected from the lower part of the unit, are preserved mostly as complete valves. Shell thickness, sculpture pattern and umbonal angle suggest a free-living, inactive swimming life habit.
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Authors and Affiliations

Fernanda Quaglio
Rowan Jane Whittle
Andrzej Gaździcki
Simões Marcello Guimarães
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Abstract

The algal microfossil Bolboforma reticulata Daniels and Spiegler is recorded from the Oligocene-Miocene glacio-marine sediments of King George Island, South Shetland Islands, Antarctica. The record extends the geographic extent of the species to Antarctica.

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Authors and Affiliations

Andrzej Gaździcki
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Abstract

Five new derivatives of 4,6-di(thiophen-2-yl)pyrimidine (DTP) were designed by structural modification with the aim to tune the electro-optical and charge transfer properties. The effect of oligocene and oligocenothiophene incorporation/substitution was investigated on various properties of interests. The smaller hole reorganization energy revealed that compounds 1-5 might be good hole transfer contenders. The smaller hole reorganization energy of newly designed five DTP derivatives than the pentacene showed that prior compounds might be good/comparable hole transfer materials than/to that of pentacene. The computed electron reorganization energy of DTP derivatives 1-5 are 124, 185, 93, 95 and 189 meV smaller than the meridional-tris (8-hydroxyquinoline) aluminum (mer-Alq3) illuminating that electron mobility of these derivatives might be better/comparable than/to referenced compound.

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Authors and Affiliations

A. Irfan
A.R. Chaudhry
A.G. Al-Sehemi
S. Muhammad
R. Jin
S. Tang
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Abstract

A lithological profile and measurements of the orientation and spacings of natural discontinuity planes were carried out in the Górka-Mucharz sandstone excavation (Krosno Beds, Outer Carpathians, Poland). In addition, the density of the discontinuities was assessed by measuring their spacings using oriented digital photographs of the quarry walls. An orthophotomap was also used in assessing the orientation and density of fractures with the tools available in QGIS. It was shown that digital image analysis can be used as an alternative to direct field measurements, especially in situations where access to an outcrop is difficult. The distributions of spacings larger than 40 cm, obtained by direct measurements and based on digital images of the quarry, were comparable. As a consequence, both measurement techniques yielded similar values of the quantity of blocks (QB), which differed by less than 2% for the minimum block volume in the range 0.4-1.0 m3 and by 6-7% for larger blocks. On the other hand, measurements of discontinuity spacings that were taken on the basis of an orthophotomap can only serve to estimate the approximate maximum value of this parameter. However, the use of orthophotomaps gives a more explicit spatial pattern of the main vertical joint sets than direct measurements in the quarry.

The analysis results also showed the following: (i) the presence of tectonic disturbances visible at the highest level of the deposit; (ii) higher density of set A fractures with planes deepening in the NE direction and a considerable reduction of the QB parameter, particularly in the peripheral NE and SW parts of the deposit; (iii) differences in the orientation of the discontinuity system between particular beds. The variable density of the discontinuities in the excavation is related to the presence of the faults that limit the Górka-Mucharz deposit.

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Authors and Affiliations

Beata Figarska-Warchoł
ORCID: ORCID
Grażyna Stańczak
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Abstract

Solitary corals of the genus Flabellum are described from the Lower Oligocene glaciomarine strata of the Polonez Cove Formation of King George Island, West Antarctica. This is the oldest record of the genus from Antarctica.

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Authors and Affiliations

Andrzej Gaździcki
Jarosław Stolarski
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Abstract

An additional account on the Oligocene cyclostome Bryozoa has been made from the glaciomarine sediments of the Low Head Member (= Pecten conglomerate of Barton 1965) of the Polonez Cove Formation on King George Island (South Shetland Island, West Antarctica). The following genera have been recognized for the first time in Paleogene of Antarctica: Crista, Bicrisia, Exidmonea, Filisparsa and Mecynoecia. Paleoecological interpretation of the bryozoan assemblage implies that the fauna lived in shallow water at a depth of around 50 m.

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Authors and Affiliations

Urszula Hara
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Abstract

Shallow−marine deposits of the Krabbedalen Formation (Kap Dalton Group) from Kap Brewster, central East Greenland, yielded rich dinoflagellate cyst and pollen− −spore assemblages. Previously, this formation yielded also rich mollusc and foraminifer age−diagnostic assemblages. A Lower Oligocene age of the Krabbedalen Formation seems to be supported by the dinoflagellate cyst assemblage analysis, while the pollen−spore as− semblages point to a wider stratigraphic age range within Oligocene–Middle Miocene.

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Authors and Affiliations

Krzysztof Birkenmajer
Przemysław Gedl
Elżbieta Worobiec
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Abstract

The Blue Dyke and Jardine Peak are subvertical hypabyssal intrusions cutting a stratiform volcanic sequence in the Admiralty Bay area on King George Island (South Shetlands, Antarctica ). The rocks are porphyritic, crystal-rich basaltic andesites. Tiny zircon crystals were used for single grain SHRIMP U-Pb dating. The mean ages calculated for the zircon populations from both intrusions indicates Late Oligocene (Chattian) formations. Zircon grains from the Blue Dyke gave the mean age of 27.9±0.3 Ma, whereas those from the Jardine Peak are slightly younger displaying the mean age of 25.4 ± 0.4 Ma: a Late Oligocene (Chattian) crystallization age the inferred of both these intrusions. These are much younger than previous Eocene K-Ar and Ar-Ar ages for such rocks and suggest that formation of the King George Island intrusions can be related to tectonic processes that accompanied the opening of the Drake Passage.

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Authors and Affiliations

Magdalena Pańczyk
Jerzy Nawrocki
Ian S. Williams
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Abstract

The Suborder Clupeoidei Bleeker, 1859 comprises mostly marine fishes, which form large schools feeding on plankton. The fossil record of the suborder in the Late Paleogene reveals that clupeoids were abundant in the Western, Central, as well as Eastern Paratethys. Clupeoid descriptions from the Polish Outer Carpathians (SE Poland, Central Paratethys) remain incomplete due to usage of ‘collective species’, taxonomical inaccuracies, and lack of clear links between extinct and extant representatives. In this paper we present a new clupeoid, † Beksinskiella gen. nov., from the Oligocene of the Outer Carpathians, Poland. The new genus encompasses the nominal species † Maicopiella longimana (Heckel, 1850). † Beksinskiella gen. nov. has a unique combination of characters (skull roof with frontoparietal striae; smooth opercle; 6–7 branchiostegal rays; 42–48 vertebrae; dorsal and anal fins with 21–23 rays; the last two rays of the anal fin being elongated, and the presence of a complete series of abdominal scutes with the postpelvic ones poorly developed), supporting recognition of a new genus of the Suborder Clupeoidei. Similarities and differences between fossil and extant genera of Cluepoidei are discussed to shed light on their relationship.
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Authors and Affiliations

Mateusz Granica
1
Małgorzata Bieńkowska-Wasiluk
1
Marcin Pałdyna
1

  1. University of Warsaw, Faculty of Geology, Żwirki i Wigury 93, 02-089 Warszawa, Poland
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Abstract

Brachiopods from the Chlamys Ledge Member, uppermost part of the Polonez Cove Formation (Oligocene), of King George Island, West Antarctica are represented by the undeterminable Rhynchonellida, one short-looped terebratulide Liothyrella Thomson, and two long-looped terebratellidines: Rhizothyris Thomson and Terebratelloidea gen. et sp. indet. Liothyrella is a well known genus in the Cenozoic strata and Recent waters of the Southern Hemisphere, while Rhizothyris is noted for the second time in the Antarctic region. This is the first record of brachiopods from the Chlamys Ledge Member.

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Authors and Affiliations

Maria Aleksandra Bitner
Andrzej Gaździcki
Błażej Błażejowski
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Abstract

The presented studies focus on changes in groundwater levels and chemistry, and the identification of important factors influencing these changes on short- and long-term scales in urban areas. The results may be useful for rational and sustainable groundwater planning and management in cities. The studies concerned three aquifers: (1) the shallow Quaternary aquifer, (2) the deep Quaternary aquifer, and (3) the Oligocene aquifer in the capital city of Warsaw (Poland). The spatial variability of groundwater recharge was determined and its changes in time were characterized. The characteristics of groundwater levels were based on long-term monitoring series. The results indicate that urban development has caused overall reduction in infiltration recharge (from 54 to 51 mm/ year), which is particularly clear in the city suburbs and in its centre, where land development has significantly densified during the last 30 years. Studies of groundwater levels indicate variable long-term trends. However, for the shallowest aquifer, the trends indicate a gradual decrease of the groundwater levels. In the case of the much deeper Oligocene aquifer, groundwater table rise is observed since the 1970s (averagely c. 20 m), which is related with excessive pumping. Based on the studied results, the groundwater chemistry in the subsurface aquifer indicates strong anthropogenic influence, which is reflected in multi-ionic hydrogeochemical types and the occurrence of chemical tracers typical of human activity. The Oligocene aquifer is characterized by a chemical composition indicating the influence of geogenic factors.
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Authors and Affiliations

Ewa Krogulec
1
Tomasz Gruszczyński
1
Sebastian Kowalczyk
1
Jerzy J. Małecki
1
Radosław Mieszkowski
1
ORCID: ORCID
Dorota Porowska
1
Katarzyna Sawicka
1
Joanna Trzeciak
1
Anna Wojdalska
1
Sebastian Zabłocki
1
Daniel Zaszewski
1
ORCID: ORCID

  1. University of Warsaw, Faculty of Geology, Żwirki i Wigury 93, 02-089 Warszawa, Poland

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