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1

First Cenozoic glaciers in West Antarctica

100%
Birkenmajer K., Gazdzicki A., Krajewski K. P., Przybycin A., Solecki A., Tatur A., Yoon H. I.
Polish Polar Research
|
2005
|
tom 26
|
nr 1
3-12
One of the most significant global climatic events in the Cenozoic was the transition from greenhouse to icehouse conditions in Antarctica. Tectonic evolution of the region and gradual cooling at the end of Eocene led to the first appearance of ice sheets at the Eocene/Oligocene boundary (ca. 34 Ma). Here we report geological record of mountain glaciers that preceded major ice sheet formation in Antarctica. A terrestrial- valley-type tillite up to 65 metres thick was revealed between two basaltic lava sequences in the Eocene- Oligocene Point Thomas Formation at Hervé Cove - Breccia Crag in Admiralty Bay- King George Island- South Shetland Islands. K-Ar dating of the lavas suggests the age of the glaciation at 45-41 Ma (Middle Eocene). It is the oldest Cenozoic record of alpine glaciers in West Antarctica- providing insight into the onset of glaciation of the Antarctic Peninsula and South Shetland Islands.
2

Recent ostracods from Admiralty Bay, King George Island, West Antarctica

100%
Majewski W., Olempska E.
Polish Polar Research
|
2005
|
tom 26
|
nr 1
13-36
Ostracods from Admiralty Bay on King George Island (South Shetland Islands) represent 29 podocopid species, belonging to 19 genera, one cladocopid and six myodocopid species. They were recovered from Recent marine and/or glacio-marine sediment samples from water depths of up to 520 m. These ostracods constitute a variable assemblage, which is overall typical for the Antarctic environment. Shallow-water assemblages tend to be more variable in terms of frequencies and species richness than deep-water assemblages. The later are low in numbers and remain relatively high diversities. Overall, no linear relation between ostracod assemblage-composition and environmental features analyzed was recognized.
3

Monothalamous foraminifera from Admiralty Bay, King George Island, West Antarctica

100%
Majewski W., Lecroq B., Sinniger F., Pawlowski J.
Polish Polar Research
|
2007
|
tom 28
|
nr 3
During the late 2007 austral summer, 20 sediment samples were collected in Admiralty Bay (King George Island, South Shetlands, West Antarctica) from 8 down to 254 m water-depth (mwd). The samples yielded abundant assemblage of monothalamous benthic foraminifera, belonging to at least 40 morphospecies. They constituted the first such collection from Antarctic Peninsula fjords and provided a new insight into this group's diversity and distribution. Among organic-walled taxa, Psammophaga sp., Allogromia cf. crystalli- fera, and three morphotypes of Gloiogullmia were especially abundant. Agglutinated forms were dominated by Hippocrepinella hirudinea, Psammosphaera spp., Lagenammina spp., and various mudballs. Although, the majority of the morphotypes were known from other high-latitude locations, some were reported for the first time. Our quantitative data (>125 |m) showed the greatest differences between monothalamous foraminifera assemblages at shallowest water depths above 50 mwd. The deepest assemblages from between 179 and 254 mwd, were most similar, suggesting uniform near-bottom conditions at ~200 mwd throughout the Admiralty Bay.
4

Brachiopods from the Lower Miocene of King George Island, West Antarctica

84%
Bitner M. A., Crame J. A.
Polish Polar Research
|
2002
|
tom 23
|
nr 1
75-84
5

Benthic foraminiferal communities: distribution and ecology in Admiralty Bay, King George Island, West Antarctica

84%
Majewski W.
Polish Polar Research
|
2005
|
tom 26
|
nr 3
159-214
During the austral summer of 2002/2003 the author collected 38 marine and/or glacio-marine sediment samples from Admiralty Bay on King George Island (South Shetland Islands, West Antarctica). Recent "living" (Rose Bengal stained) and "dead" (subfossil) benthic foraminifera represented by 105 species belonging to 65 genera are recognized in samples from water depths of up to 520 m. They show large spatial variability. Four distinctive foraminiferal zones within the fjord of Admiralty Bay were recognized and analyzed in terms of environmental conditions. The zones are: restricted coves, open inlets, intermediate-, and deep-waters. The major environmental factors, which dictate foraminiferal distribution, are closely related to bathymetry and distance to open sea. Sediment composition and chlorophyll content appear to have minor influence on foraminiferal communities. Most diverse, deep-water faunas dominate water-depths below 200 m, which seems to be the lowest limit of atmospheric and meltwater influence. In waters shallower than 200 m, environmental features, affecting distribution of various benthic foraminiferal assemblages, appear to be sedimentation rate and hydrographic isolation. The results of this study gives promise to use the Admiralty Bay foraminiferal distribution pattern as a paleo- environmental tool for shallow- to intermediate-water Quaternary marine research in fjord settings of the South Shetland Islands.
6

The helminth fauna of some notothenioid fishes collected from the shelf of Argentine Islands, West Antarctica

67%
Laskowski Z., Zdzitowiecki K.
Polish Polar Research
|
2005
|
tom 26
|
nr 4
315-324
he infections of four fish species, Trematomus newnesi, T. bernacchii, Lindber- gichthys nudifrons and Harpagifer antarcticus with parasitic worms, in the coastal zone off the Vernadsky Station (Argentine Islands, West Antarctica) are described. Data on infections are compared with previous results from Admiralty Bay at the South Shetland Islands. Indices of infection are for each host-parasite relationship. In total, 16 taxa of parasites were recorded: 6 digeneans, 3 larval cestodes, 4 (adult and cystacanth) acanthocephalans, and 3 (adult and larval) nematodes. Fifteen of them have been previously recorded in Notothenia coriiceps from this area. Hence, the number of parasitic taxa recorded in this region increased from 21 to 22. Either the digenean Macvicaria georgiana or acanthocephalan Corynosoma pseudohamanni were dominants in different hosts. Trematomus bernacchii was the most strongly infected, especially with M. georgiana (prevalence 100%, mean abundance 113.7). The infection parameters of the majority of parasites were lower at the Vernadsky Station than in the Admiralty Bay, especially for host-parasite relations with larval cestodes and nematodes. The presently reported study have confirmed that the southern range of distribution of two acanthocephalans, Aspersentis megarhynchus and Corynosoma hamanni extends south to the area near the Argentine Islands.
7

Reconstruction of postglacial paleoproductivity in Long Lake, King George Island, West Antarctica

67%
Yoon H., Khim B., Lee K., Park Y., Yoo K.
Polish Polar Research
|
2006
|
tom 27
|
nr 3
189-206
A sediment core (LS-1) collected from Long Lake in King George Island, South Shetland Islands (West Antarctica) was analyzed for a variety of textural, geochemical, iso- topic and paleontological properties together with 14C age dates. These data combined with published records of other studies provide a detailed history of local/regional postglacial paleoproductivity variation with respect to terrestrial paleoclimate change. The lithologic contrast of a lower diamicton and an upper fine-grained sediment demonstrates glacial recession and subsequent lake formation. The upper fine-grained deposit, intercalated by mid-Holocene tephra-fallout followed by a tephra gravity flow, was formed in a lacustrine environment. Low total organic carbon (TOC) and biogenic silica (Sibio) contents with high C/N ratios characterize the diamicton, whereas an increase of TOC and Sibio contents characterize the postglacial lacustrine fine-grained sediments, which are dated at c. 4000 yrBP. More notable are the distinct TOC maxima, which may imply enhanced primary productivity during warm periods. Changes in Sibio content and S13C values, which support the increasing paleoproductivity, are in sympathy with these organic matter variations. The uniform and low TOC contents that are decoupled by Sibio contents are attributed to the tephra gravity flows during the evolution of the lake rather than a reduced paleoproductivity. A very recent TOC maximum is also characterized by high Sibio content and S13C values, clearly indicating increased paleoproductivity consequent upon gradual warming across King George Island. Comparable with changes in sediment geochemistry, the occurrence and abundance of several diatom species corroborate the paleoproductivity variations together with the lithologic development. However, the paleoclimatic signature in local terrestrial lake environment during the postglacial period (for example the Long Lake) seems to be less distinct, as compared to the marine environment.
8

Pre-glacial sedimentary facies of the Point Thomas Formation (Eocene) at Cytadela, Admiralty Bay, King George Island, West Antarctica

59%
Mozer A.
Polish Polar Research
|
2012
|
tom 33
|
nr 1
9

Antarktyda

42%
Schnayder E.
Wszechświat
|
1957
|
nr 06
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