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The 36th Japanese Antarctic Research Expedition (JARE-36) consisted of 40 wintering members and 16 summer members with one atmospheric chemist from Germany. The icebreaker SHIRASE left Tokyo on November 14,1994,and arrived at Syowa Station on December 24 via Fremantle. All cargo of about 1070t was unloaded by January 12,1995. Constructions to replace old buildings and facilities at Syowa Station and for a large HF radar system and others were carried out by February 14. For the Deep Ice Coring Project at Dome Fuji, an oversnow traverse to/from the Dome Fuji Station (77°19′S, 39°42′E, 3810m a.s.l.) was performed; the first wintering at the new station was started by 9 members from January 29. Observations on geology, geodesy, biology and others were carried out around Syowa Station, Lutzow-Holm Bay and Riiser-Larsen Massif. Observations on physical, chemical and biological oceanography, geomagnetism and others were made through the voyage of the SHIRASE from Tokyo via Antarctica to Sydney. The summer party of JARE-36 returned together with the JARE-35 wintering party to Tokyo from Sydney by air on March 28 with satisfactory results.

Oxygen isotopic contents of fresh snow drifts in the katabatic wind zone were measured. The samples were collected at a stage before forming deposited snow layers throughout the year. Besides, the oxygen isotope profiles of deposited snow layers at the same place were obtained. The δ^O contents of the snow drifts had high values in summer (-30～-40‰); in winter, values were generally low (above -50‰) but sometimes there were high values similar to those in summer. Deviation of relations between air temperature at sampling time and δ^O contents of the snow drifts under different weather conditions is discussed. Vertical profiles of δ^O contents of deposited snow are supposed to show a wide annual range and complicated annual variation, if such snow drifts accumulated continuously. However, those of deposited snow actually seen in the surface layers usually show a narrow range (-35～-45‰) and simplified pattern. Positions of maxima and minima in δ^O profiles of deposited snow have good correlations with layering of ice crusts which were formed during hiatus periods of snow deposition. These results indicate the importance of change of the isotopic contents after snow deposition for understanding the isotope profiles of deposited snow.

Vertical profiles of oxygen isotopic contents in deposited snow were obtained in the region where katabatic winds prevail (Mizuho Station : 70.7°S, 44.3°E, 2230m), the inland dome-like plateau (Dome Camp : 77.0°S, 35.0°E, 3761m) and the transitional zone between them (Advance Camp : 74.2°S, 35.0°E, 3198m). At Mizuho Station, the δ^O contents have high values around the hiatus layers. However, synchronous relations cannot be found between the neighboring profiles, since snow was exchanged due to deposition and erosion by strong winds. Inter-annual variations of oxygen isotopic contents in snow have been preserved better in the inner parts of the ice sheet between the three zones observed in this study. The profile at Dome Camp has good correlation with the inter-annual variation of summer temperature at 5000gpm above the South Pole. This result suggests that the temperature at this level above the South Pole is representable for air temperature condition over the inland ice sheet, and the meteorological conditions in summer have a strong effect on the transition of the oxygen isotopic content of snow after deposition due to evaporation-sublimation.

Glaciological observations on the high plateau in the East Queen Maud Land, Antarctica, were carried out along a route of the oversnow traverse, by the 25th and 26th Japanese Antarctic Research Expeditions in 1984 and 1985. The surface topography of the dome-like plateau (Valkyrjedomen, which is the second highest in Antarctica) and the positions of ice divides were determined clearly. The position and altitude of the highest place of the dome are 77°22′S, 39°37′E and 3807m a.s.l. Snow drift samples were collected along the route from Mizuho Station to Valkyrjedomen and were melted carefully in a snow vehicle. The value of electric conductivity of the melted snow samples at 0℃ was obtained before storing in the pre-cleaned bottles. In a home laboratory, pH measurements of the samples were carried out. It was revealed that the high electric conductivity and low pH values were found among the snow samples collected in the dome area, especially around the region higher than 3600m a.s.l. The region has the different glaciological characteristics from those in the katabatic wind region, that is, the lower degree of the surface inclinations, the lower net accumulation, the more smooth surface morphology, the lower ram hardness of surface snow layer and the higher lapse rate of snow temperature at 10m depth. Taking the comparatively higher concentration of artificial radio nuclides reported in the other Antarctic inland area into consideration too, the glacio-chemical environments in the Antarctic inland region are thought to be characterized by the transportation of the stratospheric aerosols or gases.

The weather conditions from September to January in the vicinity of the Mizuho Plateau, the area between the coast and 72°S, are discussed on the basis of the weather observations made during the traverses of JARE-10 (the 10th Japanese Antarctic Research Expedition) in 1969-70 and the previous traverses. The mean wind speed of about 8-10 m/s is obtained from the observations. It is found that the observed orientations of sastrugis and pitted patterns show seasonal variations. The wind direction is constant in inland, but diurnal variations of the wind direction were observed. When the wind direction changes counterclockwise to the north from the prevailing wind direction, it can be expected that weather is getting worse. The flow lines of the prevailing winds in the vicinity of the Mizuho Plateau are drawn from the orientations of sastrugis and other features. The pressure variation in inland about 350 km distant from Syowa Station was similar to that at Syowa Station. Sea-salt particles were detected at 71°S and 43°E during a light snow or ice prisms falling when the wind was weak with its direction changing counterclockwise from the prevailing wind direction.

The observations were made on net ablation of some of sastrugi and drifts (like barchanoids) in the area subjected to strong katabatic winds between 100 and 200 km inland from the Antarctic coast near Syowa Station in September and November, 1969 and in January, 1970 by means of the stake measurements. The net ablation of hard sastrugi during the period from November to January (mean 2.8 cm/month) was larger than that from September to November (mean 0.7 cm/month). The large amount of ablation from November to January may be attributed to the increase of solar radiation which accelerates sublimation-deflation on the surface of sastrugi. On the other hand, net ablation of soft sastrugi and drifts from September to November was larger than that from November to January. The large amount of ablation from September to November may be attributed to the strong erosion by the wind, since sastrugi and drifts were soft. Since they were hardened or flattened after erosion by the wind from September to November, the ablation from November to January was not larger than that from September to November. Since the rate of ablation at the top of sastrugi and drifts was higher than that at the surrounding surface in late spring and summer, and the bulk of yearly accumulation is deposited in autumn and winter, it can be said that surface irregularities are supposed to be built up in winter, then smoothed in summer. The best season for yearly stake measurements is considered to be the end of summer when the more accurate value of mean net accumulation may be expected since surface irregularities are less than any other season. Gow (1965) and WELLER (1969) gave some explanation for the higher rate of net ablation of sastrugi than the surrounding surface at the South Pole and Plateau Station. However, since the area of this report is located where the katabatic winds are strong as mentioned above, the situation is different from their case. According to the logarithmic increase of wind velocity, the top of sastrugi is expected to be subjected to stronger winds, hence greater wind erosion, than the surrounding surface.

1969年12月,第10次日本南極地域観測隊の内陸調査旅行のさい,筆者らはやまと山脈南東,南緯71°50',東経36°15'付近の裸氷斜面上で隕石を9箇発見,採集した.これは,隕石採集を主目的として,計画的になされたものではないので,隕石の分布ひんどはかなり高そうである.この付近の地域や,類似の氷床の構造のところでは,今後も発見できそうである.採集された隕石はエコンドライト1箇,コンドライト8箇で,岩質からみて,少なくとも6種類(コンドライト5種,エコンドライト1種)の隕石である.

第8次(1967年),第9次(1968年),第10次南極地域観測隊(1969年)において実施された昭和基地周辺の海氷上(北の浦およびオングル海峡)における,積雪量と海氷厚の観測結果をまとめて報告する。北の浦海氷上における積雪量は,場所による大きな相違があるが,おおむね卓越風向の風上地域では非常に少なく,風下の東オングル島に近い地域では多いという傾向が見られた。最も積雪量の多い所では,積雪深が9月から10月頃に120cmを越え,最も少ない所では,年間を通してほとんど積雪がなかった。北の浦全域の平均積雪深は,1968年,69年とも最大約30cmで,11月末から急激に消耗を始め,年間を通じてはほぼゼロとなった。昭和基地周辺の一冬氷は,9月から11月頃まで成長を続け,最大氷厚は110～140cmであった。

1969年11月～1970年1月の間に行なわれた第10次日本南極地域観測隊の内陸調査旅行のさい,昭和基地の東南東方向150km,南緯69°39',東経43°20',高度約1,600mの大陸氷床上に新しいモレーンが発見確認された.モレーンは直経数10mから数100mのものが3個,約N10°W方向に3kmの間に分布している.モレーンは巨視的に見て,谷地形の中に分布しており,東方は裸氷帯で,クレバスの多い急な登り斜面である.モレーンの礫は,亜角礫と角礫が大部分を占める.岩質は細粒片麻状閃緑岩が主で,桃色正長石花崗岩質の脈がよく発達しているものが多い.この種の岩石はリュツォ・ホルム湾沿岸ややまと山脈よりも,宗谷海岸北方に多い.モレーンの地形,氷,岩質の特徴から,モレーンの源は,現在の場所の比較的近くではないかと推察される

Reports that post-depositional change of isotope concentration was investigated in a temperate snow pack. Daily snow pit studies that were carried out at Moshiri, Hokkaido; Isotope analysis that was conducted on snow particles and the liquid water in between the particles, and on the precipitation and the runoff water (from the bottom of the snow pack) that collected during the observation period; Finding that the oxygen isotope concentration in the liquid part was smaller than the solid part of the wet snow; Difference between the isotope concentrations of the liquid and the solid that was low in the surface snow layer, but increased at the bottom; Results that suggested that isotope fractionation took place between the liquid and the solid, when liquid water (formed by melting at the snow surface layer) flowed groundwards.

Positive degree-day factors for ice ablation on Yala Glacier, central Nepal, Xiao. . . [ABSTRACT FROM AUTHOR]