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Volcanic geological, petrological and geochemical characteristics of the Tertiary volcanic rocks from the Fildes Peninsula, West Antarctica show that magma evolution was a process of dissipation of heat energy exchanged energy and mass occurring between the magma system and its surrounding environments, and with the feature of dynamic equilibrium and periodicity (stage). In the study volcanic rocks of different types commonly exhibit a multi-grade composite texture and the derivative magmas produced by differentiation of parent magmas in the magma chamber show a zonal structure in the high-level-magma chamber which represent self-organization phe-nomenon of the nonequilibrium process in magmatism. The self-organization phenomenon is dissipative structure formed under given conditions.
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Systematical analyses of lithology, grain sire, mineral composition, microbiological thanatocoenoses and other geological proxies from the sediments of piston core Pci0, drilled in the central part of the Bransfield Strait, have been carried out. Based on the above data, together with the shipboard investigation, the 753 cm long core sediments reveal the last 112. 5 ka deposits of the study area under the glacial-marine environment. The sediments includes biogenic silica deposit, volcanic debris deposit and turbidity current deposit. Among them, the biogenic silica deposit is dominative not only in the highstand water/interglacial stage, but also in the lowstand water/glacial stage. The difference of sedimentation between the two stages was that the terrigenous debris content and the sedimentation rate were lower in the lowstand water/glacial stage.
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Two reversal geomagnetic excursions are detected by systematically palemagnetic measurements of the Core NP93-2 from the Prydz Bay, Eastern Antarctica. One is found in 60 to 67. 5 cm from the top of the core, and the l4C dating age of layer 67. 5 cm to 72. 5 cm is 10315± 800 a B. P. It is estimated that the geomagnetic excursion occurred at 9980 ~8880 a B. P., and perhaps was the record of the Gothenburg geomagnetic excursion (about 12000 a B. P. ). The other is found in 27. 5, 32. 5 cm, and the l4C dating age is 5390 ± 600 a B. P., with which no generally acknowledged geomagnetic excursion can be compared. But a few reports of geomagnetic excursions can be used for comparing with, Zhu et al. reported a geomagnetic excursion at 4980~ 4770 a B. P. from peat in Beijing, Wang et cd. reported a geomagnetic excursion at 5120±110aB.P.fromCoreNS-89-76 inNanshaWatersandZhouefa/.reporteda geomagnetic excursion at 6400~6000 a B. P. from Core QC2 in Yellow Sea. Whether the studied geomagnetic excursion does exist or whether those reported geomagnetic excursion are the same one is worth further study.
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The concentrations of 13 elements in the metal of 52 Antarctic irons have been reported and these irons have been classified based on the structures and their Ga, Ge, Ni, Ir and other trace elemental contents. The 52 iron meteorites assigned to chemical group consist of 16 of IABt 12 of IIAB, 1 of HE, 3 of IIIAB, 1 of IIICD, 1 of IVA and 18 of ungrouped irons. The IAB, IIICD and HE iron meteorite groups are considered to be of nonmagmatic origin. Nonmagmatic IAB, IIICD and IIE irons formed as individual pools of a chondritic body. The other groups, IIAB, IIIAB and IVA show the evidences of having originated by fractional crystallization of a metallic magma. The slopes on element-Ni trends in the magmatic are generally higher than in the nonmagmatic groups. Most interestings are the high abundance of ungrouped and IAB (47. 2% and 27.8%, respectively) and low abundance of IIIAB (5. 8%). Antarctic irons of the group abundances can be distinguished from non-Antarctic irons v which provide the information about previously unsampled parent planets, mass, shock and collision, as well as nebula regions.
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Homolodromia inflata (Förster) described in this paper is found from the Miocene Cape Melville Formation of the glacio-marine sediments in King George Is-land, Antarctica. A comparison is made between the genera Homolodromia and Antarctidromia and a discussion is also made on the taxonomic placement of the genus Homolodromia in the Brachyura, we would like to consider that the genus Antarctidromia previously identified by Förster, may be a synonym of the genus Homolodromia.
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This paper deals with the results of composition of CS-C1S hydrocarbons in the regions of the Bransfield Strait. The multivariate statistical analysis is made to recognize the characteristics of the sediments, resulting in that the C5-C15 hydrocarbons contain n-alkanes, iso-alkanes, cyclo-alkanes, aromatic compounds and their substituted compounds as well. The multivariate statistical analysis also shows that stations G-25 and G-27 have the extreme values of factor after rotation.
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Based on the analysis of the soil-forming factors, pedogenic processes and the soil properties in the study area, this paper is to propose the soil geographico-genetic classification of maritime-climatic Sub-Antarctic regions. The soils of the Fildes Peninsula were classified into 3 soil-orders, 4 suborders and 13 soil groups, and then the re-lationship between the soil distribution and the environment was discussed.
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In this paper Pc3 pulsations at Great Wall Station of Antarctica are analyzed statistically from August 16 to November 20, 1990.The occurrence frequency, frequency and polarization are studied for Pc3 pulsation events. The mechanisms of excitation and propagation of Pc3 pulsations at Great Wall Station are discussed theoretically.
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