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Correlation between the body length and the diameter of the compound eye of the Antarctic
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Redetermination of the metamorphic age of the garnet-bearing mafic granulite from the Sφstrene Island, Esat Antarctica has been made and an isochron of whole rock-garnet-pyroxene-plagioclase is obtained, giving an age of [604±28 (2σ) ] Ma. It is pointed out that this age represents the time of peak granulite facies metamorphism of the area. As to the geological relation of the Sφstrene Island with the Bolingen Islands and the Larsemann Hills to the east, it is deduced from the rcxrk assemblages, meta- morphic superposition, spatial changes and metamorphic ages between the above re-gions that the degree of the superposition of the later low pressure metamorphism is becoming stronger from west to east. While the evolution of the earlier medium pressure to later low pressure implies probably the substages of the same metamorphic cycle.
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The Fossil Hill Formation of the type section composed chiefly of the sedi- mentary-volcaniclastic breccia and tuffites can be divided into two cycles of sedimentation. The thermal fluid was active in the coarse volcaniclastic deposits of the lower cycle, it led to the formation of laumontite, analcite, albite and regularly hybrid mineral of interlayered chlorite and montmorillonite ^which are absent from the upper cycle, and to the transportation and concentration of some of trace elements between the coarser tuffites and the overlying fine tuffite bed at the upper part of this cycle. So-called "rain print" and "mud crack" actually are non-sedimentary originally, they were formed respectively by shedding of the small zeolitized concretions on the bedding plane and tectonic pressed stress. The evidences indicate that the Fossil Hill Formation of the Fossil Hill section was deposited in an intermontane lake affected by both volcanic action and seasonal flood under the condition of worm and moist climate.
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21 species foraminifera, including in 14 genera were encountered from 39 samples of core PC10, which were drilled in the Bransfield Strait of Antarctic Peninsula. They are divided into 3 assemblages as follow: 1. Siliceous shell assemblage; 2. Calcareous shell assemblage; 3. Mixed shell assemblage. The Siliceous shell assemblage occurred in normal deep-sea, with weaker water dynamic condition. The Calcareous shell assemblage was formed by turbidity flow, while the Mixed shell assemblage represented intense to weaker water dynamic condition. It changed from warm to cold to warm during the late Quaternary.
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Analyses of Foraminiferal fauna in the core NP93-2 of the Prydz Bay, Antarctica shows that the sediments are rich in Foraminifera in which planktonic Foraminifera make up 26.3% of the total number of Foraminifera and the arenaceous agglutinated benthic Foraminiferal assemblages are prevailing with 57.9% of total number of benthic Foraminifera. The typical benthic Foraminiferal assemblage of Mil-iammina arenacea represents an assemblage of deep-water arenaceous agglutinated. Variations of content of warm and cold species of planktonic Foraminifera reflect the paleoclimatic changes and also reveal the paleo-environmental changes in this region and its relationship with the global changes. Other paleoccanographic and palcoclima-tological questions, such as water depths carbonate dissolution are also discussed.
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The Holocene ostracode are analyzed from the core sample NG93-1 collected in the Great Wall Bay, Antarctica during 1992～1993. Totally 11 genera 21 species have been identified in the sediments, of which the most abundant is ljoxoreticulatum fcdlax % the second abundant are
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The biomass of ice algal communities in coastal sea ice off Zhongshan Station, Antarctica were monitored from April to December 1992. The maximum thickness of ice cover was 1.74 m in November/December and covered-snow was less than 35 cm in depth throughout the study period. Brown layers occurred in 2～5 cm of the ice bottom in late April and November, with chlorophyll
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The typical glacial-marine sedimentation has been recorded from core NP93-2 in the Prydz Bay, Antarctica. The sedimentation prcxrcsses, sedimentary environment and paleoclimate variations since 12937 a B. P. have been discussed, based on grain size, mineral composition and micropaleontological data, etc.. The climate variation cxrcurred at 10 ka, which expressed that there were increased inputs of terrigenous elastics. The climate change once again but temporarily took place at late Holocene.
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