摘要:

Over a number of years research on a stretch of the southeastern glacier margin of Kötlujokull in South Iceland, 8 km in length, has focused on correlating the manner of glacier drainage with the genesis of sandar, exemplified by the recent evolution of the glacier foreland. The research has yielded the following results. During an initial period, beginning prior to 1945 and ending between 1966 and 1975, a belt of moraines about 1 km wide was destroyed in stages, except for a few remnants, by 11 outbreaks of subglacial meltwater at different times and locations along the glacier front. These outbursts were associated with the genesis of “ordinary”; sandar, which are referred to here as “low sandar.”; The main evolution of these sandar, and especially of their proximal parts, took only a few days and was correlated with a discharge of meltwater under high hydrostatic pressure from a subglacial tunnel mouth. The details of such an outburst are described. Prior to 1975 a general change occurred from the subglacial drainage which had prevailed earlier to predominantly supraglacial drainage. After 1978 only one subglacial meltwater exit remained, at the western corner of the glacier. The increasing violence of the supraglacial drainage was perhaps caused by structural changes in the glacier. During this second period this supraglacial drainage gave rise to the formation of a belt of finegrained sandar which largely covered the “low sandar”; and hence are called “high sandar.”; In contrast to the subglacial drainage the supraglacial drainage has not led to any serious destruction of the moraines. “Low”; and “high”; sandar differ in their sedimentological genesis. The high sandar in front of Kötlujökull are fan‐shaped bodies of sand, corresponding to a special model of facies. This evolution occurred partly under conditions of a high flow regime, and with continuous formation of antidunes.

ISSN:0273-8457    

DOI:10.1080/10889378509377242

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Natural ice wharves are used on a regular basis for unloading ships at the Soviet Antarctic station at Molodezhnaya and Novolazarevskaya, and less frequently at Mirnyy. Recession of the ice fronts due to thermal abrasion is posing problems at both locations, due to resultant shallowing of water depths alongside. The authors discuss the feasibility of stabilizing the retreating ice fronts by means of cooling the ice through the use of heat exchangers, or of creating artificial ice wharves by building up a massive ice body through repeatedly flooding the surface of the fast ice, as has been successfully achieved by the Americans at McMurdo Sound.

ISSN:0273-8457    

DOI:10.1080/10889378509377243

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Although no deposits of oil or gas have been found in Antarctica thus far, the available geological/geophysical data indicate that there is considerable oil and gas potential. Some 8–10 sedimentary basins with oil and gas potential are identified by the authors. A series of basins lies around the margin of the East Antarctic Platform. These include the Wilkes Land Basin, the Victoria Land Basin and the Prydz Bay Basin. A further group of sedimentary basins is associated with the transitional area between the East Antarctic craton and the West Antarctic fold zone; these include the Weddell Sea Basin, the Ross Sea Basin, and the Byrd Basin. Finally, two smaller basins, the Bellingshausen Sea Basin and the Amundsen Sea Basin are located on the northern flank of West Antarctica.

ISSN:0273-8457    

DOI:10.1080/10889378509377244

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

The authors have attempted to assess the potential coal reserves of Antarctica. Several coal‐bearing sedimentary basins are located around the margins of the East Antarctic Platform. The most extensive coal‐bearing deposits, Permian and Triassic in age, are located in the Transantarctic Mountains, where they extend for 2500 km from Victoria Land to the Horlick Mountains. Another significant basin, Permian in age, is that in the Prince Charles Mountains. The authors present a detailed description of the stratigraphy of the coal‐bearing sequences in each of these major basins. Estimates of reserves are as follows: 10.8 billion tons in the Prince Charles Mountains; 6 billion tons in the Queen Alexandra Range in the Transantarctic Mountains, and 130 million tons in southern Victoria Land, also in the Transantarctic Mountains. Some information is also provided on minor coal‐bearing deposits located in the nunataks around the Weddell Sea and Filchner Ice Shelf.

ISSN:0273-8457    

DOI:10.1080/10889378509377245

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

摘要:

Extensive sampling of krill(Euphausia superbaDana) was carried out from the polar research vesselAkademik Knipovichin the Lazarev Sea in March 1981. Analysis of the results revealed some very interesting patterns in the distribution and age structure of the population of these crustaceans. The highest concentrations ofE. superbawere found in the extreme south near the Antarctic coast, in the waters of the Antarctic Coastal Current; a secondary, minor concentration was found farther north in the waters of the Weddell Drift. Larvae concentrations revealed the same pattern. Most interestingly, the size of larvae and the state of the females revealed thatE. superbaspawns earlier in the south than in the north of the Lazarev Sea. The authors hypothesize that the control may be the occurrence of a plankton “oasis,”; i.e., an area of particularly abundant phytoplankton, in the south of the Lazarev Sea, linked to an area of abnormally fresh water associated with ice retreat and with quasi‐stationary gyrals on the margins of the Antarctic Coastal Current.

ISSN:0273-8457    

DOI:10.1080/10889378509377246

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

ISSN:0273-8457    

DOI:10.1080/10889378509377247

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor

ISSN:0273-8457    

DOI:10.1080/10889378509377241

出版商:Taylor & Francis Group    

年代:1985

数据来源: Taylor