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    30 December 1989, Volume 1 Issue 4 Previous Issue    Next Issue

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    OBSERVATION AND RESEARCH ON THE TURBULENT FLUXES OF MOMENTUM AND SENSIBLE HEAT OVER MIZUHO STATION, EAST ANTARCTICA
    1989, 1 (4):  1-11. 
    Abstract ( 1293 )   PDF (634KB) ( 879 )  

    This paper describes the results of observation on the fluxes of momentum and sensible heat over Mizuho Station (70°41' 53 " S, 44°19 ' 54 " E), East Antarctica. The data were collected by using the meteorological tower 32m high at this station in 1979-1981 period. These fluxes were evaluated by semiemperical flux-profile relation of Monin-Obukhov similarity theory from these observed data, and the calculated result was compared with that over the West Pacific Tropical Ocean area and Beijing area. 1.For the stable atmosphere the drag coefficient CDS is (1.05±0.01)×10-3, and for the unstable atmosphere it (CDUN) is (1.26±0.15) x 10-3.The drag coefficient CDUN for unstable atmosphere is larger than that (CDS) for stable atmosphere. The magnetude of the drag coefficient CD is obviously correlated with atmosphere stability. Bisides, the drag coefficient CDUN for unstable atmosphere is obviously correlated with the gradient Richardson number Ri. 2.This Antarctic area is a cold source on the Earth where the sensible heat flux has obviously annual variation and different diurnal variation- for different seasons. In winter (August) the sensible heat flux absorbed from the atmosphere is about 114W. the largest among all seasons. It is about 94W in autumn (May), 24W in spring (October), and about 12W in summer (January), the least among all seasons, i.e. only about 1/10 of that in winter. The diurnal variation of the sensible heat flux for different seasons are different over this station. In autumn and winter the sensible heat flux has no obvious diurnal variation. This is similar to that over the West Pacific Tropical Ocean area. However, it is essentially different. The Antarctic area is a cold source where the sensible heat is transferred from atmosphere to ice (or snow) surface, but the West Pacific Tropical Ocean area is a heat source where the sensible heat is transferred from sea to atmosphere. In spring and summer the sensible heat flux has obvious diurnal variation. The daytime sensible heat flux is positive, and transferred from ice (or snow) surface to atmosphere. The nighttime sensible heat flux is negative and transferred from atmosphere to ice (or snow) surface. This is similar to that over Beijing area. But on the average for a day, it is also essentially different. The Antarctic area is a cold source where the net transfer of sensible heat is negative. But Beijing area is a heat source where the net transfer of sensible heat is positive.

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    THE MEDIUM-RANGE OSCILLATION OF METEOROLOGICAL ELEMENTS OVER GREAT WALL STATION ON ANTARCTICA
    1989, 1 (4):  12-20. 
    Abstract ( 1295 )   PDF (553KB) ( 1005 )  

    A methed of multi-spectral analysis is used to study the spectral characteristics of surface and upperlevel meteorological elements over the Great Wall Station (62°12' S, 58°57' W) on Antarctica and their phasecorrelation, propagation of mean oscillation at 500hPa level in the Southern Hemisphere and their corresponding synoptic sense. the results are summed up as follows: 1.Over the sub-Antatctic zone, as in the Northern Hemisphere there generally exist quasi- weekly oscillation and quasi-biweekly oscillation. In different seasons the oscillations of meteorological elements are different: in winter season quasi-biweekly oscillation is dominant, while in summer season quasi-weekly oscillation is dominant. 2.From the Earth's surface to the lower stratosphere there is a distinct quasi-weekly oscillation at each isobaric surface, but the most intense oscillation appears at 200-300hPa, and the oscillations of height and temperature are propagated downward. 3.Both in winter and summer seasons the quasi-biweekly oscillation are propagated from west to east, and the mean velocity of its propagation is about 7-17 longtitude / day. 4.The quasi-biweekly oscillation and the quasi-weekly oscillation over the sub-Antarctic zone are closely related to the activity and intensity variation of polar vortex at 500hPa, while at 1000hPa they refleet an interaction between the circumpolar depression and the sub-tropical high over Antatctica. The quasi-biweekly oscillation may be a reflection of inherent oscillation of the polar vortex, where as the quasi-weekly oscillation is a reault of forced oscillation by external disturbance. A large number of calculations and analysis made reveals the features of medium-range oscillation over the sub-Antarctic zone. The results are of significance for understanding the behaviour of synoptic dynamics and making the weather forecast. This work is supported by National Committee for Antarctic Research.

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    DISTRIBUTION OF OXYGEN-MINIMUM LAYER AND FACTORS CONTROLLING ON IT IN AREAS ADJACENT TO SOUTH SHETLANDS AND NORTH OF ADELAIDE, ANTARCTICA, IN SUMMER
    1989, 1 (4):  21-27. 
    Abstract ( 1373 )   PDF (538KB) ( 1164 )  

    In this paper the distribution of oxygen-minimum layer and factors controlling on it in the sea areas adjacent to South Shetlands and north of Adelaid, Antarctica, in summer is discussed.The correlation coefficient between oxygen content, temperature, salinity, density, pH and apparent oxygen utilization (A.O.U.) in the oxygen-minimum layer is calculated and correlation between them is discussed. The correlation between oxygen, temperatur and A.O.U are negative (r= -0.9688, -0.9945, respectively) .The variation of oxygen-minimum layer is mainly controlled by temperature and biochemical process in deep water.

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    THE BRANSFIELD TROUGH-A CENOZOIC RIFT
    1989, 1 (4):  28-35. 
    Abstract ( 1257 )   PDF (650KB) ( 1053 )  

    The South Shetland Trench and Islands and the Brandsfield Trough form a trench-are-trough system which is only one around Antractica, and is a high neotectonic activity area in Antarctica. the Bransfield Trough is a deep trough under 1300-2600m deep water. Its eastern part is deeper than the western. Topographically its both sides are obviously asymmetric. Analysis of data on gravity, geomagnetism, volcanism and seismicity indicates that the Bransfield Trough is a Cenozoic rift. The morphology and geotectonic characteristics of the Bransfield Trough are similar to that of Okinawa Trough, though its formation machenism is different distinctly form later. The trough has developed in two stages: 1) The subduction has caused the back-arc spreading, and 2) after the large-scale subduction and spreading of Drack Passage, the mantle upwelling led the lithosphere to be extended, thinning and rifting, and then a series of grabens and horsts were formed. Mafic magma from the mantle has gushed out along the axis of the rift. The spreading centre was magrating toward the ocean, thus an asymmetirc rift was formed. The trough is spreading and where a new oceanic crust is formed.

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    DETRITAL MINERALS IN THE SEDIMENTS OF CORE S_11 AND SEDIMENTATION IN SEA AREA WEST OF SOUTH SHETLAND ISLANDS
    1989, 1 (4):  36-43. 
    Abstract ( 1351 )   PDF (633KB) ( 963 )  

    There are more than thirty of detrital minerals in sediments of core S11. Analysis of heavy mineral assemblages reveals that pyroxene and amphibole are the dominant heavy minerals in the sediments. The feldspar and quartz are the dominant light minerals. According to the characteristics of the detrital mineral assemblages in the vertical direction, four types of heavy mineral assemblages can be found: 1) Pyroxene-amphibole-epidote-garnet, 2) Pyroxene-amphiple-epidote-authigenic pyrite, 3) Amphibole-pyroxene-epidote-sheet minerals, 4) Pyoxene-amphibole-epidote-sheet minerals-authigenic pyrtite.And two light mineral assemblges: 1) feldspar-quartz-volcanic glass fragment, and 2) feldspar-quartz were defined. The mineralogical characteristics of sediments show their specific source rocks. On the basis of the different mineral assemblages, the sediments in core S11 consist of four layers from the uppermost part to the lower part as follow: 1) Upper layer of pyroclastic minerals, 0-125cm; 2) Middle layer of pyroclastic minerals, 125-255cm; 3) The layer of pyroclastic minerals (pelagic sands), 255-282cm; 4) Lower layer of pyroclastic minerals, 282-341cm. The source of the pelagic sands was discussed in this paper. The materials of layers 1,2 and 4 have possibly come from intermediate-basic volcanic rocks and volcanic eruptions on the South Shetland Islands. The sediments of layer 3 mainly come from intermediate-acidic igneous rocks on Antarctic Peninsala. Thus they might be formed by turbidite sedimentation.

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    PRELIMINARY EXPLORATION ON THE ENVIRONMENTAL BACKGROUND VALUES IN FILDES PENINSULA AREA OF KING GEORGE ISLAND, ANTARCTICA
    1989, 1 (4):  44-51. 
    Abstract ( 1375 )   PDF (404KB) ( 1017 )  

    Environmental background values are indicated as the contents and occurrence states of chemical elements in the basic units of the environment, such as in rocks, soil, water, atmosphere, biosphere, etc. non-mineralized and undisturbed by exotic substances under the normal conditions. They reflect the inherent characteristics of the chemical composition of these units of the environment in their developmental process. The Antarctic continent, as an original environment not or seldom influenced by human beings, is an ideal area for study of the background values of the environment. With the rapid development of investigations by various countries, it is an urgent task at present time to explore the background values of the environment on Antarctica in order to make the environment policy for keeping the "clean earth ", the Antarctic continent intact. This paper presents the preliminary results on main chemical composition of basic units of the environment, such as rocks, primitive soil (weathering crust) , sediments, ground water, meteoric water, aerosol, biosphere, etc in the Fildes Peninsula area of the King George Inland. and the methods for physical and chemical analysis of them. The study provides a scientific basis for making an evaluation of the environmental quality, setting up standards of an environment, and studying the regularties of migration and transition of chemical elements, as well as for the reasonable development and utilization of the resources on Antarctica in the future. The research is supported by the National Natural Science Foundation of China.

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    CARBON-14 DATING OF THE SURFACE SEDIMENTS FROM SEA AREA NORTHWEST OF THE ANTARCTIC PENINSULA AND ITS ERRORS
    1989, 1 (4):  52-56. 
    Abstract ( 1458 )   PDF (355KB) ( 1298 )  

    This paper deals with a result of radiocarbon dating of the surface sediments dreged from the sea area northwest of the Antarctic Peninsula and measurement of modern radiocarbon on two specimens (living byophtes and penguin bones ) collected on King George Island. The information of two modern carbon samples indicates that the concentration of car-bon-14 in the sediments from the sea area northwest of the Antarctic Peninsula is different from that in atmospheric CO2.This difference in 14C concentration resulted in increasing age of surface sediments is preliminarily discussed in the paper. The author points out that the 14C age of the surface sediments in the sea area northwest . of the Antarctic Penisula is 456 years older than the actual ages at least (the increasing concentration of 14C was caused by nuelar explosion which is not considered) .

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    ESTABLISHMENT OF THE SURVEYING SYSTEM IN THE CHINESE CREAT WALL STATION AREA, ANTARCTICA
    1989, 1 (4):  57-64. 
    Abstract ( 1544 )   PDF (560KB) ( 988 )  

    In the Great Wall Station area, Antarctica, a complete and accurate surveying system has been established during three years of the Antarctic surveying research expedition. In this paper, the author discusses the surveying methods for establishment of the system, the model for data processing and accuracy of analysis of the reaults. 1. Establishment of the Great Wall Station geodetic coordinate System.The datum point was set up on the West Mountain to west of the Grest Wall Station. The datum parameters were determined by satellite Doppler positioning method.The WGS-72 reference ellipsoid was adopted and the coodinate is B = 62°12'59" 782(S), L = 58°57'52" 546(W). Then Gauss horizontal Cartesian coordinate system was established by using Gauss direct projection formula. In the Great Wall Station area, a horizontal trilateration control network was also set up taking the datum point as origin. The coordinates of network points were com- puted using rank defect free network adjustment. 2.Establishment of the Great Wall Station elevation system.The geoid of Great Wall Station was determined by using combined artificial tide gage and automatic tide gage data. From the connected measurments, an elevation of levelling origin is determined to be 6.741m. The Great Wall Station normal height system was then established after setting up the first order levelling network. In the Great Wall Station area, the elevation control points are coincident from horizontal control points and were observed with eletromagnetic distance triangulated height method.The height differences were calculated with accurate formula. In the observation, the deflection of the vertical correction and the refraction effect correction were added in. After step-by-step approach adjustment, the elvations of control points were obtained by weighted mean of adjustment values. The accuracy of elevation is similar to IV-order levelling. 3.Establishment of the Great Wall Station gravity reference system. A gravity basic point was set up in front of the office building. From the connected measurments with South American Intenational Gravity Standard Network point, a gravity value is determined to be 892208.68± 0.04 mgal. The gravity network points in the Great Wall Station area are coincident with horizontal control points and were measured with Lacoste-G gravimeter. Gravity values of the points were obtained by adjustment.The geoid undulation and the vertical deflection were also computed with Stokes and Vening-Menesz integration. The geoid map and free-air gravity anomaly map of the Great Wall Station area were also drawn.

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    ANALYSES AND COMPARISON OF THE COMPONENTS OF PROTIENS AND AMINO ACIDS IN LIVER, PANCREAS AND STOMACH OF ANTARCTIC SEALS
    1989, 1 (4):  65-68. 
    Abstract ( 1480 )   PDF (283KB) ( 1055 )  

    In present paper the analytical results on the components of protiens and amino acids in the liver, pancreas and stomach of Antarctic fur Seal i.e. Kerguelen fur seal (Arclocephalus gazalla) and Weddell seal (Leptongchotes Weddelli) are reported. It has been found that the contents of protiens in pancreas of two species of seals are high. 17 kinds of amino acids were found in the stomach of both these seals beside that tryptophane was hydradatezed, and glutamine and asparagine were transformed directly into aspartic and glutamic acids in the process of determination. Proline is absent in pancreas of Weddel seal. Methionine and proline have not been detected out in liver of both species. The absence Of these two kinds of amino acids in liver is surprising since our determination is made for general protiens. Methionine is also relatively low in pancreas and stomach of these two species. Moreover, the components of amino acides in liver, pancreas and stomach of both seals tend to be fairly similar, with highest contents of aspartic and glutamic acids and alanine, valine, leucine and lysine. The result is significant for study of polar biology.

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