Recent foraminifera from Goulden Cove of King George Island, Antarctica

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1 vol. 24, no. 1, pp. 3 12, 2003 Recent foraminifera from Golden Cove of King George Island, Antarctica Andrzej GAŹDZICKI 1, 3 and Wojciech MAJEWSKI 1, 2 1 Instytt Paleobiologii PAN, l. Twarda 51/55, Warszawa, Poland <gazdzick@twarda.pan.pl; wmaj@twarda.pan.pl> 2 Zakład Biologii Antarktyki PAN, l. Ustrzycka 10, Warszawa, Poland 3 Zakład Biologii Polarnej i Oceanobiologii UŁ, l. Banacha 12/16, Łódź, Poland ABSTRACT: Recent foraminifera represented by 24 species belonging to 20 genera are recognized in marine and/or glacio marine sediment samples collected at water depths of p to 75 m in Golden Cove (Admiralty Bay) on King George Island, West Antarctica. The foraminifer assemblages are dominated by benthic taxa, sch as Globocassidlina biora and Miliammina arenacea, the two most abndant species in the stdied biocenosis. Key words: Antarctica, King George Island, Foraminifera, Recent. Introdction The Recent Antarctic foraminifera have been known since the early part of the XX centry (see Heron Allen and Earland 1922) and have beeen stdied for many years (Crespin 1960), most recently by Fillon (1975), Anderson (1975), Osterman and Kellogg (1979), Bernhard (1987), Ward and Webb (1986), Ward et al. (1987), Mackensen et al. (1990), Ishman and Domack (1994), Violanti (1996) and Mayer and Spindler (2000). Dring the astral smmer of 1986/1987 J. Błaszyk i R. Wiśniewski (members of the 11 th Polish Antarctic Expedition to Arctowski Station) collected srface sed iment samples from Golden Cove (Ezcrra Inlet) in Admiralty Bay on King George Island (Soth Shetland Islands), West Antarctica (Fig. 1). Ten of these samples, collected at three stations from the water depths between abot 20 and 75 m (Figs 1 2), have been analyzed and the reslts are presented here. The reslts represent a pilot investigation, the monographic stdy on benthic foraminifera from the Admiralty Bay is crrently being prepared by the jnior athor sing sed iment cores recovered dring the 2002/2003 Antarctic season. Pol. Polar Res. 24 (1): 3 12, 2003

2 4 Andrzej Gaździcki and Wojciech Majewski 60 S King Seymor George I. Island A EMERALD POND HILL King George ICEFALLS Island Admiralty Bay B C A R D O Z O C O V E DUFAYEL ISLAND E Z C U R R A I N L E T Point Thomas Panorama Ridge ADMIRALTY BAY ARCTOWSKI STATION (Poland) I III II G O U L D E N CYTADE LA C O V E W A R S Z A W A I C E F I E L D C Fig. 1. Map showing the foraminiferal sample locations (Stations I III) in Golden Cove, King George Island (C). Insets show the location of King George Island within Antarctica (A) and Admi ralty Bay in King George Island (B). The investigated foraminifer collection is hosed at the Institte of Paleo biology of the Polish Academy of Sciences (Warszawa) nder the cataloge nm ber ZPAL F.45. All SEM micrographs were also taken at the Institte of Paleo biology. Setting The fjord like Admiralty Bay, the largest bay on King George Island consists of Martel Inlet in the east, Mackellar Inlet in the center, and Ezcrra Inlet in the west (see Battke 1990). The Ezcrra Inlet is sbdivided by Dfayel Island and Pond Hill into Cardozo Cove in the north west and Golden Cove in the soth west (Figs 1 2). The Admiralty Bay coastline is heavily glaciated with ice cliffs terminating at sea level. The sbmarine morphology of the bay and its inlets is a re slt of glacial erosion, mainly dring the Pleistocene (Birkenmajer and Marsz 1999). The Golden Cove is abot m deep. The srface sediment samples were collected from the cove at three stations: I from 20 m, II from 35 m, and III from 75 m water depth (Fig. 1C).

3 Recent foraminifera from Golden Cove 5 Dfayel Island GOULDEN COVE CARDOZO COVE EZCURRA INLET Fig. 2. View of Ezcrra Inlet and Golden Cove as seen from the Point Thomas (Panorama Ridge). Methods Ten ndistrbed sediment samples were collected sing a tbe sampler. The sediment was washed over a 125 µm sieve. Several hndred of benthic and a few planktic foraminifera were picked from reside recovered at each station; how ever, the nmber of specimens picked from each sample varied significantly which prevented qantitative analysis of the foraminiferal material. Nevertheless, the large nmber of recovered specimens jstified presenting the qalitative reslts. The classification scheme of the Order Foraminiferida sed here is that of Loeblich and Tappan (1988). Reslts Foraminifera were a common constitent of all samples collected at stations I, II, and III. We recognized 20 genera and 24 species (Figs 3 7, Table 1), bt the nmber of taxa varies between the three stations. The most diverse fana was re covered from the shallowest Station I (20 m). It inclded 23 species groped into19 genera. In contrast, foraminifera from Station II (35 m), representing inter mediate water depths among the three sites, inclded 9 species belonging to 7 gen era. The deepest fana from Station III (75 m), exhibited comparatively high di versity with 21 species and 18 genera. Both calcareos and aggltinated benthic foraminifera were fond at all stations; however, the planktic Neogloboqadrina pachyderma (Fig ) was fond only at Stations I and III.

4 6 Andrzej Gaździcki and Wojciech Majewski Table 1 Foraminiferal occrrences at Golden Cove (Admiralty Bay), King George Island. Srface sediment samples have been taken at three stations from different water depths. Taxa I 20 m Stations II 35 m III 75 m Psammosphaera fsca?saccammina sp. Lagenammina arenlata Miliammina arenacea Reophax sp. Labrospira jeffreysii Labrospira wiesneri Paratrochammina bartrami Portatrochammina antarctica Spiroplectammina biformis Pyrgo elongata Bolivina psedopnctata Rosalina globlaris Cibicides reflgens Frsenkoina fsiformis Astrononion antarcticm Astrononion echolsi Nonionella iridea Pllenia sbcarinata Cassidlinoides parkerians Cassidlinoides sp. Globocassidlina biora Globocassidlina sp. Neogloboqadrina pachyderma Foraminiferal assemblages were dominated by Globocassidlina biora (Fig ) at all sites. However, fanas at Station I and to a lesser extent at Station III, inclded significant nmbers of other taxa, predominantly Globocassidlina sp. (Fig ), Miliammina arenacea (Fig. 3.6), and Portatrochamina antarctica (Fig. 4.4). At Station I, Spiroplectammina biformis (Fig. 4.5), Cassidlinoides parkerians (Fig. 6.2), Reophax sp. (Fig. 3.7), Nonionella iridea (Fig. 5.8) and Frsenkoina fsiformis (Fig. 5.5) also occrred in significant nmbers.

5 Recent foraminifera from Golden Cove m 3a 3b 7 4a 4b 6b 5a 5b 6a Fig Psammosphaera fsca Schlze, 1875; 3a b.?saccammina sp.; 4a b, 5a b. Lagena mmina arenlata (Skinner, 1961); 6a b. Miliammina arenacea (Chapman, 1916); 7. Reophax sp. 1 3, 6 Station III; 4, 5, 7 Station I.

6 8 Andrzej Gaździcki and Wojciech Majewski 1 5b 5a 2a 2b 3a 3b 3c 4a 4b 4c Fig.4.1.Labrospira wiesneri Parr, 1950; 2a b. Labrospira jeffreysii (Williamson, 1858); 3a c. Paratrochammina bartrami (Hedley, Hrdle et Brdett, 1967); 4a c. Portatrochammina antarctica (Parr, 1950); 5a b. Spiroplectammina biformis (Parker et Jones, 1865). 1, 3, 5 Station I; 2, 4 Station III.

7 Recent foraminifera from Golden Cove 9 1a 1b 2 5 3a 3b 8 4a 4b 4c 6a 6b 7a 7b Fig. 5. 1a b. Pyrgo elongata (d Orbigny, 1826); 2. Bolivina psedopnctata Höglnd, 1947; 3a b. Rosalina globlaris d Orbigny, 1826; 4a c. Cibicides reflgens de Montfort, 1808; 5. Frsenkoina fsiformis (Williamson, 1858); 6a b. Astrononion antarcticm Parr, 1950; 7a b. Astrononion echolsi Kennett, 1967; 8. Nonionella iridea Heron Allen et Earland, , 5, 7 8 Station I; 4, 6 Station III.

8 10 Andrzej Gaździcki and Wojciech Majewski 1a 1b 2b 2a 3a 3b 4b 4a 5a 5b 7b 6a 6b 7a Fig. 6. 1a b. Pllenia sbcarinata (d Orbigny, 1839); 2a b. Cassidlinoides parkerians (Brady, 1881); 3a b. Cassidlinoides sp.; 4a b, 5a b. Globocassidlina biora (Crespin, 1960); 6a b, 7a b. Globocassidlina sp. 1, 4 Station III; 2 3, 5 7 Station I.

9 Recent foraminifera from Golden Cove 11 1a 1b 2a 2b Fig. 7. 1a b, 2a b. Neogloboqadrina pachyderma (Ehrenberg, 1861). Station I. Comparative and conclding remarks The Antarctic bays and fjords like Admiralty Bay on King George Island, rep resent areas in which glacio marine sediments have been accmlating at least since the Pleistocene. The occrrence of Recent foraminifera in sch areas de pends on nmeros physical factors inclding lithology of sediments, oxygen and organic concentrations, as well as bathymetry. Unfortnately, at present, or data do not allow s to assess the importance of these factors to or samples. The most dramatic differences in foraminiferal composition from Golden Cove are between Station I, and Stations II and III. These differences are difficlt to ex plain in ecological terms. The absence of planktic foraminifera and significantly re dced diversity of fanas recovered from Station II, sggest either preservational bi ases or preparational artefacts. Nevertheless, the overall composition of benthic as semblages, with the clear dominance of Globocassidlina biora, with Miliammina areanacea as the second abndant species, and with Psammosphaera fsca, Spiro plectammina biformis, and Portatrochamina antarctica relatively common are in agreement with foraminiferal assemblage data presented by Li and Zhang (1986) and Zhang (1994) from the srface sediments of the Great Wall Bay (Maxwell Bay) on King George Island.

10 12 Andrzej Gaździcki and Wojciech Majewski Acknowledgements. We thank Jansz Błaszyk and Rajmnd Wiśniewski for collecting samples and srveying the locational data. Special thanks go to Tomasz K. Bamiller (Ann Ar bor, MI), Jan Pawłowski (Genève) and Peter Noel Webb (Colmbs, OH) for their critical re views and comments on this manscript. References ANDERSON J.B Ecology and distribtion of foraminifera in the Weddell Sea of Antarctica. Micropaleontology 21(1): BATTKE Z Admiralty Bay, King George Island. Map 1: Institte of Ecology, Polish Academy of Sciences. Warsaw. BERNHARD J.M Foraminiferal biotopes in Explorers Cove, McMrdo Sond, Antarctica. Jornal of Foraminiferal Research 17(4): BIRKENMAJER K. and MARSZ A Sbmarine glacial relief at Ezcrra Inlet, Admiralty Bay, King George Island (Soth Shetland Islands), West Antarctica. Blletin of the Polish Academy of Sciences, Earth Sciences 47(4): CRESPIN I Some Recent foraminifera from Vestfold Hills, Antarctica. Science Reports, Tohok University, Sendai, Japan, 2 nd Ser. (Geol.), Special Volme 4: FILLON R.H Late Cenozoic foraminiferal paleoecology of the Ross Sea, Antarctica. Micro paleontology 20(2): HERON ALLEN E. and EARLAND A Protozoa. Part III Foraminifera. British Antarctic (Terra Nova) Expedition Natral History Report. Zoology 6(2): ISHMAN S.E. and DOMACK E.W Oceanographic controls on benthic foraminifers from the Bellingshasen margin of the Antarctic Peninsla. Marine Micropaleontology 24: LI YUAN FANG and ZHANG QING SONG Recent foraminifers from Great Wall Bay, King George Island, Antarctica. Acta Micropalaeontologica Sinica 3(4): LOEBLICH A.R., Jr. and TAPPAN H Foraminiferal genera and their classification. Van Nostrand Reinhold. New York. 970 pp. MACKENSEN A., GROBE H., KUHN G. and FÜTTERER D.K Benthic foraminiferal assemblages from the eastern Weddell Sea between 68 and 73 o S: distribtion, ecology and fossilization po tential. Marine Micropaleontology 16: MAYER M. and SPINDLER M Seasonal changes in abndance and mobility patterns of benthic foraminiferans in the Potter Cove (King George Island, Antarctica). In: W. Davison, C. Howard Williams and P. Broady (eds), Antarctic ecosystems: models for wider ecological n derstanding. Christchrch, New Zealand: OSTERMAN L.E. and KELLOGG T.B Recent benthic foraminiferal distribtion from the Ross Sea, Antarctica: relation to ecologic and oceanographic conditions. Jornal of Foraminiferal Re search 9(3): VIOLANTI D Taxonomy and distribtion of recent benthic foraminifers from Terra Nova Bay (Ross Sea, Antarctica), Oceanographic Campaign 1987/1988. Palaeontographia Italica 83: WARD B.L., BARRETT P.J. and VELLA P Distribtion and ecology of benthic foraminifera in McMrdo Sond, Antarctica. Palaeogeography, Palaeoclimatology, Palaeoecology 58: WARD B.L. and WEBB P.N Late Qaternary foraminifera from raised deposits of the Cape Royds Cape Barne area, Ross Island, Antarctica. Jornal of Foraminiferal Research 16(3): ZHANG BINGGAO Foraminifera from the srface sediments in the Great Wall Bay of King George Island, Antarctica. In: Yan bin Shen (ed.), Stratigraphy and palaeontology of Fildes Peninsla, King George Island, Antarctica. Science Press, Received November 27, 2002 Accepted Febrary 5, 2003