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  1. 6 Geological Quarterly
  2. 5 Polish Journal of Ecology
  3. 4 Problemy Klimatologii Polarnej
  4. 2 Analityka : nauka i praktyka
  5. 2 Volumina Jurassica
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  1. 3 Rakusa-Suszczewski S.
  2. 2 Araźny A.
  3. 2 Nawrocki J.
  4. 2 Pańczyk M.
  5. 2 Polkowska Ż.
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1
Content available Changes in extreme temperature indices at the Ukrainian Antarctic Akademik Vernadsky station, 1951-2020
Khrystiuk Borys, Gorbachova Liudmyla, Shpyg Vitalii, Pishniak Denys
Meteorology Hydrology and Water Management. Research and Operational Applications
|
2022
|
Vol. 10, Iss. 1
95--106
EN
In the late 20th century, warming on the Antarctic Peninsula was most pronounced compared to other parts of Antarctica. However, air temperature showed a significant variability, which has become especially evident in recent decades. Thus, the investigation of air temperature trends on the Antarctic Peninsula is important. This study examines the extreme air temperature at the Ukrainian Antarctic Akademik Vernadsky station, located on Galindez Island, Argentine Islands Archipelago, near the Antarctic Peninsula. For 1951 to 2020, based on the daily air temperature data, the temporal trends of extreme air temperature were analyzed, using 11 extreme temperature indices. Based on linear trend analysis and the Mann-Kendall trend test, the TXn, TNn, TN90p, and TN90p indices showed an upward trend, whereas theFD0, ID0, TN10p, TX10p, and DTR indices showed a downward trend. Among them, annually, FD0, ID0, and TN10p significantly decreased by –0.427 days, –0.452 days, and -0.465%, respectively, whereas TXn and TNn increased by 0.164℃ and 0.201℃, respectively. The indices TXx and TNn showed no statistically significant trends. The average annual difference between TX and TN (index DTR) showed a nonsignificant decreasing trend at –0.029℃ year-1 . Thus, for the period of 1951-2020, the Ukrainian Antarctic Akademik Vernadsky station was subjected to warming.
2
Content available An enigmatic theropod Cryolophosaurus: reviews and comments on its paleobiology
Yun Changyu
Volumina Jurassica
|
2019
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Vol. 17, no. 1
103--110
EN
Cryolophosaurus is a genus of theropod dinosaur that is characterized by its distinctive crest formed by dorsally expanded lacrimals. Although its fossils are rare, currently recognized materials suggest this taxon was the largest predator in the Early Jurassic times in Antarctica, indicating it was the apex predator in its ecosystem. The skeleton of Cryolophosaurus bears both advanced and basal characteristics of theropods, making its position within theropod phylogenetic tree controversial. Its unusual anatomical features, size, and the habitat located close to the Jurassic polar circle all differ from other Early Jurassic theropods, indicating it was one of the most ecologically significant taxon of all theropods.
3
Content available Operation of seagoing cruise ships in polar waters of the Antarctica
Wolski A.
Zeszyty Naukowe. Transport / Politechnika Śląska
|
2017
|
z. 96
215--219
EN
As maritime tourism has been developing dynamically in recent years, including cruises into polar areas, the author attempts to identify factors essential for the safety of navigation in those sea areas, with a specific focus on the waters of the Antarctica. The presented methods of navigation take account of hazards that are typical in polar waters. All the considerations are based on the guidelines of the Polar Code.
4
Content available Dokumentowanie geologiczne na potrzeby posadowienia obiektów naukowej stacji badawczej w warunkach polarnych
Pietrzykowski P., Dobak P., Krogulec E., Krogulec T., Małecki J.
Przegląd Geologiczny
|
2017
|
Vol. 65, nr 10/2
692--700
EN
The methodological experience and the results of observation and research have been presented as a part of an expert geological and engineering study for the planned extension of the Henryk Arctowski Polar Station on the coast of King George Island in the South Shetland Islands in Antarctica. The object is realized in an area requiring recognition of specific geodynamic conditions. According to technical requirements coming from the conceptual design project of the station (Kurylowicz and Associates, 2015) it was necessary to adopt a non-standard research program. Engineering and geological characteristics are presented in comparison with geoenvironmental considerations. The assessment of soil and rock properties was carried out in relation to the results of observations and determinations of parameters that could be assessed in the coarse-grained soils and rocks in the area of the designed object.
5
Content available Kriokonity i kriojamy w przylepie lodowej Antarktyki
Rakusa-Suszczewski S.
Problemy Klimatologii Polarnej
|
2015
|
Nr 25
119--125
PL
Kriokonity są cylindrycznymi otworami powstałymi w wyniku topnienia na lodowcu w otoczeniu ziarn mineralnych. Takie formy obserwowano na powierzchni przylepy lodowej powstałej na morzu w sąsiedztwie oazy Thala Hills na Ziemi Enderby w Antarktydzie Wschodniej. Otwory kriokonitów są większe przy brzegu niż dalej od brzegu w wyniku selekcji cząstek mineralnych wynoszonych przez wiatr z oazy. W przylepie lodowej powstają też kriojamy jako efekt topnienia lodu wokół fragmentów makroglonów, które przylgnęły do dna powstającego lodu, często wraz z lodem dennym. Kriojamy i kriokonity są więc różnego pochodzenia. Prezentowane są warunki środowiskowe i tworzenie się zespołu podlodowego.
EN
Cryoconite are cylindrical melt holes on glacial surface. Such creature were observed on surface of landfast sea ice near Thala Hills oasis in Antarctic. Holes are larger near shore than off shore depend of size of minerals selected by winds. In the land fast ice cryocavernes vere observed as effect of melting water around of macroalge attached bottom of ice. Cryocavernes are different orginate than cryoconites. Subfast ice community and environmental changes are presented.
6
Content available Badania polarne Akademii Morskiej w Gdyni
Marsz A. A., Styszyńska A.
Problemy Klimatologii Polarnej
|
2015
|
Nr 25
75--98
PL
W pracy omówiono tematykę badań prowadzonych przez pracowników Wyższej Szkoły Morskiej/Akademii Morskiej w Gdyni w wysokich szerokościach półkul północnej i południowej. W latach 1975-2015 pracownicy tej uczelni opublikowali łącznie 231 artykułów, komunikatów i sprawozdań oraz 14 pozycji książkowych o charakterze monograficznym dotyczących różnych aspektów badań polarnych. Wśród tych prac 142 pozycje dotyczyły Arktyki i 103 pozycje – Antarktyki. Podstawowa problematyka badawcza obejmowała zagadnienia zmienności i zmian warunków hydroklimatycznych w Arktyce i Antarktyce, kształtowania się warunków lodowych i problemów żeglugi w lodach oraz zagadnień uprawiania żeglugi w rejonach słabo rozpoznanych pod względem nawigacyjnym, w tym badań dotyczących batymetrii dna i geomorfologii wybrzeży. Artykuł zawiera jako załącznik bibliografię prac polarnych pracowników Wyższej Szkoły Morskiej i Akademii Morskiej w Gdyni.
EN
The paper discusses topics of research conducted by the staff of the Gdynia Maritime University in the high latitudes of northern and southern hemispheres. In the years 1975-2015 the employees of the university have published a total of 231 articles, communications and reports and 14 books of monographic covering various aspects of polar research. Among the 142 works related to the Arctic positions and 103 positions – Antarctica. The basic research problems included issues variability and change hydro-climatic conditions in the Arctic and Antarctic, the formation of ice conditions and navigation in ice problems and issues of navigation in areas poorly recognized in terms of navigation, including research on the bottom bathymetry and geomorphology coasts. The article includes as an annex a bibliography of works polar employees Gdynia Maritime University.
7
Lodowa kraina - obszar badań dla chemika analityka, cz. II - wrażliwość ekosytemu Antarktyki na obecność zanieczyszczeń
Szopińska M., Polkowska Ż.
Analityka : nauka i praktyka
|
2015
|
nr 2
62--68
PL
W literaturze termin "Antarktyka" służy do określenia zarówno samego kontynentu Antarktydy, jak i otaczającego go Oceanu Południowego oraz leżących na nim wysp. Antarktyda jest najbardziej odizolowana od pozostałych kontynetów, jednak specyficzna lokalizacja nie chroni tego obszaru przed negatywnym wpływem związanym z różnymi sferami działalności człowieka. Szeroki pas wód Oceanu Południowego stanowi barierę, która utrudnia transport zanieczyszczeń tą drogą. Dlatego lotne i średnio lotne związki chemiczne mogą docierać nad obszar Antarktydy wraz z przemieszczającymi się w tym kierunku masami powietrza (transport zanieczyszczeń na duże odległości, LRAT). Tylko w znikomym stopniu na poziomy zanieczyszczeń środowiska na tym obszarze ma wpływ działalność zlokalizowanych tam stacji naukowych.
8
Lodowa kraina - obszar badań dla chemika analityka, cz. I - badania z zakresu chemii analitycznej prowadzone na terenie Antarktyki
Szopińska M., Polkowska Ż.
Analityka : nauka i praktyka
|
2015
|
nr 1
70--77
PL
Analiza dostępnych informacji pozwala stwierdzić, że działalność człowieka w skali lokalnej i globalnej prowadzi do powolnej degradacji ekosystemów antraktycznych.
9
Content available Innowacyjny autonomiczny pojazd podwodny do badania stanu środowiska w warunkach trudnych
Chodnicki M., Jażdzewski M., Kulwicki Ł, Ławreszuk D., Panasiuk-Chodnicka A. A.
Zeszyty Naukowe Dolnośląskiej Wyższej Szkoły Przedsiębiorczości i Techniki. Studia z Nauk Technicznych
|
2014
|
Nr 3
7--16
PL
Na podstawie rzeczywistej, aktualnej wiedzy w temacie rozwoju robotów podwodnych został zaprojektowany nowy pojazd wyposażony w innowacyjne rozwiązania. Autonomiczny robot podwodny dedykowany jest do pracy w trudnych warunkach środowiskowych, wymagających odporności na wysokie ciśnienie, niskie temperatury i silne prądy, które są typowe dla regionów polarnych. W pracy opisano charakterystykę docelowego rejonu, w którym ma być używany robot podwodny, tj. Zatokę Admiralicji w rejonie Archipelagu Szetlandów Południowych. Istotnym aspektem pracy był także dobór odpowiedniego systemu sterowania, który będzie zdolny przeprowadzić pojazd przez trudne i wymagające warunki stawiane przez środowisko zewnętrzne. Kolejnym elementem projektu jest ocena istniejących systemów nawigacji. Ostatnią częścią jest opracowanie kształtu robota, odpowiedniego do warunków otoczenia z uwzględnieniem możliwości zamontowania dodatkowych urządzeń mechanicznych, elektrycznych i pomiarowych, odpowiedzialnych za wykonywanie powierzonych zadań podczas misji robota.
EN
The use of Autonomic Underwater Vehicles (AUV) continuously recording the basic environmental parameters in marine polar regions are extremely difficult. This study provides a summary and a description of the existing solutions for the AUV, their use, construction, actuators and transmitters. Based on the actual knowledge a new vehicle equipped with innovative solutions and components was designed. The underwater robot is dedicated to be working in harsh environmental conditions requiring resistance to high pressure, low temperatures and strong currents, which are typical for the polar regions. The first stage of the design process consist of selection miniature sensors, vision systems to collect information about the environment. The next step was to develop a method for processing and storing data from the measurements. There has been elaborated a special communication and data transfer for this system. An important aspect of this design is a proprietary control system, which includes selecting an appropriate drive with the control program Marek Chodnicki, Marek Jażdzewski, Łukasz Kulwicki, Dawid Ławreszuk, Anna A. Panasiuk-Chodnicka 8 according to the external conditions. Another part of the research was the review of the existing navigation systems and subsequently implementation to the designed vehicle. Then, the power system with automatic charging was elaborated, which is possible to use natural energy sources. The last part was to design the shape of the mobile robot, taking into account the environmental conditions and the possibility of mechanical and electronic devices to be installed.
10
Content available Warunki meteorologiczne na Stacji Arctowskiego (Wyspa Króla Jerzego, Antarktyka) w 2012 roku
Kejna M., Araźny A., Sobota I., Piszczek J., Łabno R.
Problemy Klimatologii Polarnej
|
2013
|
Nr 23
43--56
PL
W artykule przedstawiono przebieg warunków meteorologicznych na Stacji H. Arctowskiego (Wyspa Króla Jerzego, Szetlandy Pd., Antarktyka) w 2012 roku. Pomiary prowadzono za pomocą automatycznej stacji meteorologicznej Davis Vantage Pro+ w interwale godzinnym. Przeanalizowano zmienność ciśnienia atmosferycznego, promieniowania słonecznego, temperatury i wilgotności powietrza oraz kierunku i prędkości wiatru w cyklu rocznym i dobowym. Uzyskane wyniki porównano z dłuższym okresem pomiarowym (1977-1999) oraz z równoległymi danymi z innych stacji prowadzących pomiary meteorologiczne na Wyspie Króla Jerzego.
EN
This paper presents the meteorological conditions at the Arctowski Station (King George Island, South Shetland Islands, Antarctica) in 2012. Measurements were carried out using an automatic weather station Davis Vantage Pro+. At the Arctowski Station the global solar radiation in the period from January 19 to December 31, 2012 amounted to 2985.3 MJ.m-2 (8.60 MJ.m-2.day-1). Taking into account the full year from 1 February 2012 to 31 January 2013, this totaled to 2909.6 MJ.m-2 (7.97 MJ.m-2.day-1). The highest monthly value of solar radiation occurred in December, 567.8 MJ.m-2 (18.32 MJ.m-2.day-1) and the lowest in June, 10.4 MJ.m-2 (0.35 MJ.m-2.day-1). The average annual air temperature was –1.5°C, with the highest monthly average in January (2.4°C) and lowest in June (–5.6°C). The maximum of air temperature was 9.6°C, and the minimum –17.2°C. In 2012 the average atmospheric pressure at sea level was 989.0 hPa, with a characteristic semi-annual oscillation of pressure with two minima: in summer (January 985.3 hPa) and winter (June 979.4 hPa) and two maxima: in autumn (April 996.7 hPa) and spring (September 994.9 hPa). The lowest pressure was 946.8 hPa and the highest 1020.7 hPa. At the Arctowski Station SW, NE, E and SE winds dominate in accordance with gradient of air pressure and the local orography. The average wind speed at 2 m above the ground was 4.8 ms-1, with maximum in winter (June 6.1 ms-1) and minimum in summer (December 3.1 ms-1). The maximum wind speed exceeded 40 ms-1. Relative air humidity was 83%. There is less humidity in summer (January 78%) than in winter (July, 87%). In the course of humidity indicate the day with low humidity during foehn winds. Arctowski Station area is warmer to other regions of King George Island (about 1°C in summer and 1.5°C in winter). On the King George Island and Antarctic Peninsula area occurred increase of air temperature. At the neighboring station Bellingshausen in the years 1968-2012 air temperature rise by 0.17°C/10 years.
11
Content available remote Stulecie zdobycia południowego bieguna Ziemi
Kohler P.
Kwartalnik Historii Nauki i Techniki
|
2013
|
R. 58, nr 2
57--75
EN
The turn of the 19th and 20th centuries is a period of intensive research on Antarctica. It was during this period that the South Pole was attained. There were four expeditions which attempted to reach the South Pole: The British National Antarctic Expedition, (1901-1904), on the ship „Discovery”, was led by Robert Falcon Scott (1868-1912). The British tried to reach as far south as possible and on December 31, 1902 they reached 82°17’S. The British Antarctic Expedition (1907-1909) on the ship „Nimrod”, led by Ernest Shackleton. On January 9, 1909 the expedition reached 88°23’S. 3.The Norwegian expedition on the ship „Fram” (1911-1912), led by Roald Amundsen (1872-1928). Amundsen and Olav Bjaaland (1873-1961), Oscar Listing (1871-1936), Helmer Hanssen (1870-1956) and Sverre Hassel (1876-1928) on December 14, 1911 were the first to reach the geographic South Pole. 4. Scott’s expedition on the ship „Terra Nova” (1911-1913). The expedition to the South Pole began on November 1, 1911. Scott, Henry R. Bowers (1883-1912), Edgar Evans (1876-1912), Lawrence Oates (1880-1912) and Edward A. Wilson (1872-1912) reached the South Pole on January 17, 1912. They all died on their way back. The participants of all expeditions led to attain the South Pole carried out observations, collected various samples and conducted scientific observations. Afterwards, the collected data and objects were compiled scientifically, sometimes for many years on. During that time, the following, among other, was discovered: the shelf character of Ross Ice Shelf, the Taylor Valley (the first of the snow-free Antarctic „oases”), setting up the basic stratigraphy of the Victoria Land mountains, about 40 thousand various geological and biological specimens were brought home, the latter belonged to more than 2,000 species of plants and animals, among which, more than 400 were species new to science.
12
Content available Eocene sedimentary facies in volcanogenic succession on King George Island, South Shetland Islands : a record of pre-ice sheet terrestrial environments in West Antarctica
Mozer A.
Geological Quarterly
|
2013
|
Vol. 57, No. 3
385--394
EN
About 34 Ma ago there was a radical change of climate that led to the formation of Antarctic ice sheet. King George Island, located in the South Shetland Islands volcanic arc (northern Antarctic Peninsula region), is one of a few places in West Antarctica which shows a geological record of sedimentary environments preceding development of the ice sheet. The Eocene sedimentary facies occur in the dominantly volcanogenic succession of King George Island. They have been recognized in the Arctowski Cove and Point Thomas formations (Ezcurra Inlet Group) and in the Mount Wawel Formation (Point Hennequin Group) in Admiralty Bay, and in the Mazurek Point Formation (Chopin Ridge Group) and Lions Cove Formation (Polonia Glacier group) in King George Bay. They record a cooling trend in terrestrial environments that began at termination of the Early/Middle Eocene Climatic Optimum, and was followed by a significant deterioration of climate during Late Eocene and earliest Oligocene, directly preceding glacial conditions in the northern Antarctic Peninsula region. The ongoing research confirms the existence of three preglacial climatic stages (PGS-1 – PGS-3) during Eocene – earliest Oligocene, from humid, warm to moderate climate (PGS-1), through cool and dry climate (PGS-2), up to cold and humid conditions (PGS-3). Studies were carried out on usually fine-grained volcanoclastic sediments, containing Podocarpaceae–Araucaria–Nothofagus plant fossils assembly. Beds of reworked pyroclastic material alternate with lava flows or volcanic agglomerates, as well as ex situ blocks of Eocene volcanogenic sediments on a moraine. Calculated geochemical indices of weathering (CIA, PIA and CIW) confirm moderate to high chemical weathering under warm and humid climate conditions at the beginning and deterioration of conditions in the end of Eocene.
13
Content available Eocene relatives of cod icefishes (Perciformes: Notothenioidei) from Seymour Island, Antarctica
Bieńkowska-Wasiluk M., Bonde N., Møller P. R., Gaździcki A.
Geological Quarterly
|
2013
|
Vol. 57, No. 4
567--582
EN
Fragmentary skull bones and vertebra from the Upper Eocene La Meseta Formation on Seymour (Marambio) Island, Antarctic Peninsula have been described as gadiform fishes, informally named “Mesetaichthys”. Here we describe jaws as Mesetaichthys jerzmanskae n. g. and n. sp., and refer this taxon to the perciform suborder Notothenioidei. This group is almost unknown as fossils. Similarities to the living, ‘primitive’ nototheniid Dissostichus eleginoides are indicated in the dentition. Gadiform evolution in the Paleocene-Eocene, and the possibility of a correlation between the origin and evolution of notothenioids in connection with the deterioration of the climate in Antarctica during the Late Eocene-Oligocene is discussed.
14
Content available Warunki meteorologiczne w rejonie Stacji Arctowskiego (Wyspa Króla Jerzego, Antarktyka) w okresie 19.01-19.02.2012 roku
Kejna A., Sobota I., Araźny A.
Problemy Klimatologii Polarnej
|
2012
|
nr 22
103-116
PL
W artykule przedstawiono zróżnicowanie warunków meteorologicznych w rejonie Stacji H. Arctowskiego położonej na Wyspie Króla Jerzego (Szetlandy Południowe, Zachodnia Antarktyka) w okresie od 19 stycznia do 19 lutego 2012 r. Pomiary prowadzono na obszarze niezlodowaconym oraz na lodowcach Ekologii i Sphinx. Przeanalizowano różnice pomiędzy stanowiskami w zakresie temperatury i wilgotność powietrza (6 stanowisk), a ponadto promieniowania słonecznego oraz kierunku i prędkości wiatru (3 stanowiska). Stwierdzono znaczne zróżnicowanie topoklimatyczne związane z deniwelacjami terenu, ekspozycją, właściwościami podłoża oraz lokalną cyrkulacją atmosferyczną. Różnice te zmieniają się w cyklu dobowym oraz są ściśle uzależnione od czynników insolacyjno-radiacyjnych i cyrkulacyjnych.
EN
The topoclimatic research carried out in the summer 2012 (January 19 - February 19) showed diversity of meteorological conditions in the H. Arctowski Station surroundings. The analysed period had changeable weather conditions. An average level of solar radiation at the Arctowski Station was 14.3 MJ.m-2 a day, while its daily sums ranged from 1.7 to 24.6 MJ.m-2. Atmospheric pressure oscillated considerably from day to day. Its mean value was 980.8 hPa. The highest temperatures were recorded on the coastal lowland where the H. Arctowski Station was built (2.4°C). Air temperature at the front of the Ecology (1.6°C) and Sphinx (1.8°C) Glaciers is lower due to frequent influx of cool air masses from the glacial interior of the island. On the non-glaciated area air temperatures lower with the altitude. Between the Point Thomas and Arctowski Station the temperature difference was 0.81°C/100 m and between Jardine Peak and Arctowski Station was 1.18°C/100 m. These higher lapse-rates inform about frequent föhn processes which take place on the leeward side of the King George Island. The largest temperature lapse-rate over the glaciated areas is recorded at the contact zone between the glacier and its marginal zone. These differences grow when insolation is intensive, as it results in significant heating of the morainic ground, while the temperatures above the glacial surface remain low (ablation takes place at 0°C). Relative air humidity in the H. Arctowski Station region is high due to a large share of maritime air masses. Mean relative humidity on the seacoast ranged from 81% at the Arctowski Station and grew with the altitude to 91 on the Jardine Peak. The course of the relative humidity is significantly influenced by föhn winds, during which humidity drops to 60%. Lower relative air humidity is also recorded when dry continental air masses inflow from the sector between E through S to SW. Wind direction at the three analysed stations corresponds with the local relief layout. The prevailing winds at the H. Arctowski Station include the winds from the sectors SW (28,6%), NW (10,9%), and SE (7,9%). The most frequent winds at the front of the Ecology and Sphinx Glaciers are katabatic ones blowing along the tonque of glaciers from the Warszawa Icefield. Considering the diurnal course, the highest wind velocities at all the stations are recorded around noon as this is the time thermal and pressure lapse-rates increase above varied ground (land, maritime and glacial). Topoclimatic diversity in the H. Arctowski Station area depends on weather conditions. It grows when the weather shows insolation and radiation character, and it lowers at high cloudiness.
15
Content available Grain-size characteristics of deposits derived from different glacigenic environments of the Schirmacher Oasis, East Antarctica
Srivastava Ashok K., Ingle Pravin S., Lunge Harihar S., Khare Neloy
Geologos
|
2012
|
Vol. 18, No. 4
251--266
EN
Sediment samples have been collected from the Schirmacher Oasis and adjoining area in East Antarctica; these areas consist of polar ice, ice-free area, lakes and the coastal shelf area. The 37 samples have been analysed for their grain-size parameters and statistical relationships. The oasis is characterised by ongoing glacial processes, including deposition and erosion of the sediments by ice, meltwater and winds, thus influencing the sediments in various ways. Basic statistical grain-size parameters like graphic mean, standard deviation, skewness and kurtosis have been calculated for the four units. The sediments of all areas are almost all poorly to very poorly sorted, fine-skewed to near-symmetrical and platykurtic to leptokurtic in nature. Bivariate plots between the grain-size parameters have been interpreted. They do, apart from a few exceptions, not show any trend suggesting relationships between the sediments of the four landscape types. Both t- and F-tests have been applied on the samples, and the phi values and grain-size parameters have been analysed; these show that the group variances of the samples are not significant, but that the phi-values are significant.
16
Content available Calcareous nannofossils from the Upper Cretaceous of northern James Ross Island, Antarctica : a pilot study
Švábenická L., Vodrážka R., Nývlt D.
Geological Quarterly
|
2012
|
Vol. 56, No. 4
765--772
EN
The Czech scientific expedition to northern James Ross Island, Antarctica has tested the use of calcareous nannofossils as a possible tool for stratigraphic correlation of Cretaceous and Neogene strata. Only a few samples with poor nannofossil content gave useful information for biostratigraphy. The Lower Campanian Chiastozygus garrisonii Zone and Gephyrobiscutum diabolum Subzone, respectively, was established in the lower part of the Santa Marta Formation, Lachman Crags Member, from the common occurrence of Gephyrobiscutum diabolum associated with Broinsonia parca parca and Acuturris scotus. Deposits of the Late Miocene Mendel Formation yielded exclusively reworked nannofossils from the older Upper Cretaceous deposits. Nannofossils indicate at least two distinct stratigraphic levels: Middle Coniacian and Santonian–basal Campanian, and these must have been sourced from the immediate area. The majority of the marine deposit samples studied were barren of nannofossils, probably due to late diagenetic secondary decalcification.
17
Content available remote Physicochemical and biological characterization of soils from the vicinity of the Arctowski Polish Antarctic Station
Białkowska A. M, Grzelczyk A, Długołęcka A, Cieśliński H, Kalinowska H, Kur J, Turkiewicz M
Biotechnology and Food Science
|
2012
|
Vol. 76, nr 1
13--26
EN
Soil samples collected in 2006 from 4 different sites (Puchalski Hill and a moraine below this hill, an elephant seal colony and a penguin rookery) in the vicinity of Arctowski Polish Antarctic Station at King George Island were characterized in terms of physicochemical properties (pH, humidity, concentration of selected inorganic and organic substances), microbial colonization and the overall activity of selected enzymes (differentglycosidases and esterases). Activity of the latter enzymes was assayed by p-nitrophenyl and 4-methylumbelliferone derivatives of fatty acids (by spectrophotometric and fluorimetric method, respectively). The highest lipolytic activity was found in soils from the elephant seal colony and penguin rookery.
18
Content available The facies and biota of the oldest exposed strata of the Eocene La Meseta Formation (Seymour Island, Antarctica)
Tatur A. E., Krajewski K. P., lvalle de R. A.
Geological Quarterly
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2011
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Vol. 55, No. 4
345-360
EN
La Meseta Formation is made up of estuarine and shallow marine, fossiliferous clastic deposits 720 m thick that provides a unique record of marine and terrestrial biota of Antarctic ecosystems preceding continental glaciation in the Oligocene. The lower limit of this formation has been poorly known, and therefore it has been carefully investigated. The lowest part of the La Meseta Formation, at the southern bank of a palaeodelta, is represented by relics of a prograding sequence of sediments deposited in the wave-dominated part of a deltaic system in the offshore and lower and upper shoreface environments. The sequence is completed landwards by younger tidal plain sediments deposited at 40 m lower altitude in a relatively protected, central estuarine basin, which was dominated by tidal activity and influenced by periodic fluvial inflow. These strata were deposited during a late Paleocene or Ypresian/Lutetian lowstand of sea level, which might reflect a glaciation event or glacioisostatic rebound of land following deglaciation of hypothetic Antarctic inland glaciers. Forced regression of sea level and seaward expansion of a deltaic freshwater environment, led to local extinction of a unique assemblage of marine echinoderms, bryozoans, corals and brachiopods. These marine fossils, representing a thanatocoenosis, are perfectly preserved due to syngenetic goethite permineralisation. This process owed its origin to excess reactive iron coming from sulphide-rich bedrock through weathering processes and acid sulphate drainage of the neighbouring land area.
19
Content available Pliocene age of the oldest basaltic rocks of Penguin Island (South Shetland Islands, northern Antarctic Peninsula)
Pańczyk M., Nawrocki J.
Geological Quarterly
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2011
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Vol. 55, No. 4
335-344
EN
The Penguin Island volcano is located on the southern shelf of King George Island (South Shetland Islands, West Antarctica). Its activity is regarded as connected with the opening of the Bransfield Strait. Penguin Island is dominated by a 180 m high basaltic stratocone (Deacon Peak) with a 350 m wide crater containing a small basaltic plug inside and radial dykes, and it has a second principal vent – the Petrel Crater maar – that was formed during a phreatomagmatic eruption about 100 years ago. A low-potassium, calc-alkaline sequence of basaltic lava flows with intercalations of beach deposits (Marr Point Formation) forms the basement of the stratocone. The Marr Point Formation lava flows have never been dated before. Combined whole rock 40Ar-39Ar isotopic dating and magnetostratigraphy were applied for this purpose. We obtained an isotopic 40Ar-39Ar plateau age of 2.7 š0.2 Ma, and together with the palaeomagnetic data, middle Pliocene age (Piacenzian) is implied for the basaltic plateau of Penguin Island.
20
Content available Isotopic ages of selected magmatic rocks from King George Island (West Antarctica ) controlled by magnetostratigraphy
Nawrocki J., Pańczyk M., Williams I.
Geological Quarterly
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2011
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Vol. 55, No. 4
301-322
EN
Isotopic and palaeomagnetic studies were carried out in the central part of King George Island. Selected mafic to intermediate igneous rocks were sampled for this purpose. Single-grain U-Pb dating of zircons from basalts to dacites was controlled by a whole rock 40Ar-39Ar data and the magnetostratigraphy. Five magmatic activity phases were distinguished in the SE coast of King George Island. The oldest, late Cretaceous (Campanian) phase represented by basalts of the Uchatka Point Formation are followed by the early to middle Eocene (~53–43 Ma) phase documented by the lava flows whose ages decrease from SW to NE. Next younger magmatic activity phases were recorded by the lava flows or vertical intrusions emplaced in the late Eocene (~37–35 Ma), late Oligocene (~~28-25 Ma) and late Pliocene to Holocene. The early to middle Eocene magmatic activity phase was the most extensive, producing the largest volume of magma in the study area. The new age determinations allow a more precise and credible stratigraphic correlation of the interbeds of sedimentary rocks observed in some places within the magmatic succession. The glacial provenance of the Herv' Cove diamictite is not obvious. It might represent a mountain river environment. Intense volcanic activity could be additional factor modelling the climate conditions of Antarctica in Paleogene
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