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30 September 1989, Volume 1 Issue 3 Previous Issue    Next Issue
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PRILIMINARY STUDY OF THE SOLAR BAROMETRIC OSCILLATION ON THE GROUND SURFACE IN ANTARCICA 1989, 1 (3):  1-7.  Abstract ( 1255 )   PDF (507KB) ( 1131 )   The scientists of atmoshperic tide (e.g., Chapman, 1924) thought that the solar diurnal barometric oscillation is suppressed and the solar semidiurnal barometric oscillation is magnified. This viewpoint has continued for quite a few decades. However, the analgsis of the Antarctic data shows that the solar diurnal barometric oscillation is much stronger than the semidiurnal one on the ground surface in the Antarctica.This conclusion is agreed with that given by Gao et al. (1986) using the data of 205 stations in China. From the above, it seems to be that the solar diurnal barometric oscillation is not suppressed and the semidiurnal one is also not magnified on the ground surface in the Antarctica, thus it is different from Chapman's result. Meanwhile, it's got from the analysis that the solar semidurnal temperature oscillation is stronger than durnal one in some Antarctic winter months. It is different from that in non-polar region, which seems to be not directly produced by solar radiation. And, the solar semidurnal barometric oscillation isn't stronger than the durnal one when the semidurnal temperature oscillation is stronger than the durnal temperaure one, which probably expresses that the cause of barometric oscillation on the ground surface is complex with many effecting factors. Related Articles | Metrics

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TEMPERAL AND SPATIAL VARIATION OF TEMPERATURE IN ANTARCTIC REGION AND ITS RELATION WITH SUMMER WEATHER IN CHINA 1989, 1 (3):  8-17.  Abstract ( 1472 )   PDF (789KB) ( 1053 )   A preliminary analysis is made on the pattern of temperature variation in Antarctic region and its relation with the general circulation of the Northern Hemisphere and the summer precipitation in China, by using the monthly temperature data of 20 stations in 1958-1983 in Antarctic region, the southern oscillation index of the same period, the upper-air data in the Northern Hemisphere and the temperature and precipitaition data of China. The analysis shows that basing on the temporal and spatial temperature variation patterns in Antarctic region, the region could be divided into 3 climatic zones with different temperature variation patterns, mainly Antarctic continent, the Antarctic Peninsula and the South Pacific Ocean.Moreover, the warm and cool status in the Antarctic region could be indicated by the mean temperature of these 3 zones.The quasi 3-year oscillation cycle of the temperature variation in Antarctic regeion coincides with that of southern oscillation.Such an oscillation cycle is consistent with the features of the Northern Hemisphere circulation and the main oscillation cycle of precipitation in China.The most obvious feature is that the southern oscillation variation is preceded by the quasi 3-year temperature variation oscillation phase on Antarctic continent. Taking this into consideration, the synoptic analysis is used to further study the re- lation between warm and cool status in Antarctica and the summer precipitation and temperture in the Northern Hemisphere. The summer precipitation in China has a significant teleconntion with the temperature on Antarctic contient preceding to and at the same period.It is more worthy to note that the heigher summer temperature in Antarctic continent means more precipitation in North China and lower temperature in northeast China in summer next yesr. It is also valid reversely. The conclusions reached could provide not only the background and a supplementary means for long-ranee forecast of summer precipitation in China but also a supplementary basis for further studing the interaction between the Northern and Southern Hemisphere circulations. This word is supported by National Committee for Antarctic Research. Related Articles | Metrics

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THERMAL PROPERTIES AND TEMPERATURE DISTRIBUTION OF SNOW / FIRN LAYER IN BOREHOLE BJ ON THE LAW DOME ICE CAP, ANTARCTICA 1989, 1 (3):  18-26.  Abstract ( 1390 )   PDF (533KB) ( 1207 )   Based on detailed data on density and temperature in a shallow (about 20m deep) borehole at 1043m a.s.l.on the Law Dome Ice Cap, Antarctica, thermal properties and temperature distribution of snow/ firn in the active layer are discussed. Refering to the review of works on thermal properties of snow by Yen (1981), we suggest that the relationship between thermal conductivity (λ) and density (ρ) may be expressed by a formula, λ= 0.0784+2.697 ρ2. Then the heat transfer equation in an ununifrom medium, i.e.with variable thermal parameters, is applied and solved analytically by two approaches, laminar structure and vertical movement models.Comparison of calculated and measured temeratures indicates that the first model is bettr to describe the actual temperature distribution in snow / firn layer on a glacier, but the latter is more convenient to use because of its simplicity .The difference between calculated and measured temperatures is mainly due to the determination of boundary conditions. Related Articles | Metrics

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PALAEONTOLOGICAL EVIDENCE FOR UPPER CRETACEOUS VOLCANO-SEDIMENTARY ROCKS IN FILDES PENINSULA OF KING GEORGE ISLAND, ANTARCTICA 1989, 1 (3):  27-33.  Abstract ( 1499 )   PDF (1416KB) ( 1057 )   During the austral summer of 1987-1988, the author carried out palaeontological investigation on Fildes Peninsula of King George Island and the Northern Nelson Island. At Half Three Points located on the southeast edge of Fildes Peninsula, there two islets, on one of which the sedimentary rocks crop out with a thickness of about 5m, They mainly consist of dark-greyish tuffaceous siltstones and sandstones intercalated with carbonaceous sediments, containing pyrite and siderite, and showing fine lamellar strueture, which may belong to marsh-lacustrine deposits under a low energy and reducing condition. Many spore pollens and some leaf fossils were firstly discovered from the sedimentary intercalation of volcanic rocks at Half Three Points. The leaves comprise the following genera: Dryopteris sp., Acmopyle sp., Nothofagus sp., Dictylophyllum spp. The palynomorphs preliminarily determined includes fern (over 90%) , Deltoidospora hallii, D.Microleoides, D. regularis, D. sp., Cyathidites minor, C. sp., Osmundacidites sp., Ornatisporites sp., Asterisporites sp., Gleichiniidites senonicus, G. sp., Polypodisporites favus, P. sp.; gymnosperm ( 1-2%) , Araucariacitessp.; angiosperm ( 5%) , Nothofagidites senectus, N.nonus, N.sp., Tricolporopollenites sp. The palynomorph assemblage is characterized by abundant Gleicheniidites which was flourishing in Cretaceous. Asterisporites plays an important role in the determination of stratigraphic age. The genus is mainly distributed in Cretaceous or earlier strata. Nothofagidites firstly occurred in late Cretaceous and ranged in Tertiary and Quaternary. Therefore, the fossil-bearing beds should be of late Cretaceous age. It differs from those on Fossil Hill and near Rocky Cove on Fildes Peninsula, as the two latters belong to Eocene age. Thus, the volcanic activities seem to be set in late Mesozoic, instead of Jurassic or Paleogene in Fildes Peninsula of King George Island, The finding of flora-bearing deposits at Half Three Points fills in the gaps of late Cretaceous palynomorphs of South Shetland Islands, and is of importance for studying of geological and paleoclimatic evolutions and plate tectonics of West Antarctica. Related Articles | Metrics

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MATHEMATICAL STATISTICS OF HEAVY MINERALS AND THEIR REE AND TRCE ELEMENTS IN THE NORTHWESTERN SEA AREA OF ANTARCTIC PENINSULA 1989, 1 (3):  34-42.  Abstract ( 1290 )   PDF (638KB) ( 1109 )   Based on the analysis and mathematical statistics of quantitative data on both the heavy minerals and their REE (La, Ce, Nd, Sm, Eu, Tb, Yb, Lu), trace (Zr, Hf, Th, Ta, U, Rb, Sr, Zn, Co, Ni, Cr, As, Sc) and major (Fe) elements in the surface sediments in the northwestern sea area of Antarctic Peninsula, the authors find that the heavy minerals as the carriers of REE and trace elements shoud not be overlooked. Q-mode factor analysis of the heavy minerals provides a 3-factor model of the heavy mineral assemblages in the study area, which is mainly controlled by the origin of materials and sea currents. The common factor P1 composed mainly of pyroxene and metal minerals, and common factor P2, composed of hornblende, epidote and accesory minerals, represent two heavy mineral assemblages which are different form each other in both lithological characters and origin of materials. And common factor P3 probably results from mixing of two end members of the above-mentioned assemblages. R-mode group analysis of the heavy minerals Indicates that there are two heavy mineral groups in the sea area, which are different from each other in both genesis and origin of materials. With the help of R-mode analysis, 22 elements are divided into 3 groups and 9 subgroups. These element assemblages show that they are genetically related and that they are different in geochemical behaviors during diagenesis and mineral-forming process. In addition, the relationship between the heavy mineral assemblages and the element subgroups is also discussed. Related Articles | Metrics

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CHARACTERISTICS OF GEOTEMPERATURE AND THERMOPHYSICAL PROPERTIES OF ROCKS ON THE FILDES PENINSULA 1989, 1 (3):  43-51.  Abstract ( 1352 )   PDF (666KB) ( 994 )   During 1985-1986 and 1986-1987 expeditions on Fildes Peninsula the ground temperature in 119 spots was measured. Then thermal conductivity measurements were made on the rock samples collected. 219 data have been obtained in total. After careful analysis some pre- liminary results can be summarized as follows: 1.Most prat of Fildes Peninsula is an ice- and snowmolten land area during Antarctic summer. The localities with ground temperature below 0℃ are scattered around. The predominant ground temperature ranges from 0℃ to 2℃. 2.The localities with elevating temperatures between 2 and 4℃ are distributed near fault zones and in dyke swarmp zones, wich usually are concentrated in the paleovolcanic centers and near the intrusive bodies. 3.The localities with the highest in the peninsula ground temperature above 4℃ are totally coincident with the area of youngest (Eocene and Oligocene) volcanic breccia and lava of crateric phase where hydrothermal veins are widespreadly developed. 4.The average annual ground temperature in the southern part of Fildes Peninsula as on the continents is lower than the average annual air temperature. This may be attributable to the cooling effect due to the, thick permanent ice sheet covering the Antarctic Land. 5.The Tertiary volcanic rocks widely spread over the peninsula belong to rocks of medium thermal conductivity with a mean value of 1.69-1.78 W / mK. 6.The average thermal conductivity of the Tertiary basalts on the peninsula (1.66 ± 0.20W / mK) is about 20 percent higher than that of the contemporaneous basalts in North China (1.32 ±0.15W / mK) . This may be due to pore precipitation of silica and calcite and alteration in the Fildes Peninsula's basalts. It means, on the one hand, that during the paleovolcanic processes the strong hydrothermal activities took place on the Peninsula and, on the other hand, the thermophysical properties of basalts of oceanic and continental types are quite different. References | Related Articles | Metrics

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BIOGEOCHEMICAL RESEARCH OF ENVIRONMENTAL EVOLUTION IN CHINESE ANTARCTIC GREAT WALL STATION AREA——RECONSTRUCTION OF PALEO-RAINFALL AND THE LAST ICE-CAP MELT 1989, 1 (3):  52-60.  Abstract ( 1559 )   PDF (731KB) ( 1012 )   Evolution process of recent enviroment is usually studied by means of annual ring of tree, palynologic analysis and stable isotope assay. In this paper a new research method-biogeochemical indicator element method for study of the evolution process of recent environment is proposed. Based on researching sediments and residual plants in them from West Lake near Great Wall Station, annual rainfall variation about 4000 years and the last ice-cap melt were determined. A kind of water plants lived beneath West Lake water was identified to be Brachytheciaceae Brachythecium populeum (Hedw.)B.S.G. There are also residual plants found in the whole sediment column which is 3.4 m long. There is no obvious variation and seccession either in pattern or in structure of the plant about 4000 years, as shown by electronic microscopic observation. Ca concentration in residual plants is closely related to Ca concentration in the lake water, which are controlled by climatic condition ( mainly rainfall) . Comprehensive analysis of the sediments and residual paints in them makes us possible to suggest that the last ice-cap in this area had melted in 3500 years ago or so. Related Articles | Metrics

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SEX RATIO, FECUNDITY AND SOME REPRODUCTION CHARACTERISTICS OF KRILL (EUPHAUSIA SUPERBA DANA) IN THE WATER NORTHWEST OF ANTARCTIC PENINSULA 1989, 1 (3):  61-68.  Abstract ( 1560 )   PDF (491KB) ( 1528 )   During the First Chinese Antarctic Expedition extensive IKMT (Isaacs- Kidd midwat-er trawl) tows were made. The body length, weight, sex and sexual maturity of Euphausia superba in the samples were determined. And the fecundity of 65 gravid females were measured. Among 3640 individuals, the sex of which can be determined, only 38.1% are males. Evidence shows that the larger the body length, the smaller the percehtagp of male is. In group of 51-55 mm body length the male decreases to 20.7%. In group larger than 55mm the male drops to 8.3%. This is probably due to die off of male after pairing or due to changes in behavior. The fecundity of gravid female ranges from 2457 to 10799. The relation between body weight (W) and fecundity (F) is as follows: F=4890×W-190(r=0.9178) The weight of ovary is about 42.14% (s.d. = 6.96%) of the body weight. The average body weight of spent female (3EF) is olny 65.6% of that of gravid female. The loss of weight after spawning is as big as 34.4%. There is a great variation in sexual maturity from place to place. In water north of South Shetland Islands only adults were found in swarms. Gravid female account for 20.2%, spent female 3.4%. In the eastern mouth of Bransfield Strait, owing to the influence of Weddell drift the sexual maturity is much lower than other parts observed. No gravid and spent female were found. The sub-adults were dominant in the swarms. Related Articles | Metrics