Maps of the Arctic Basin Sea Floor: a History of Bathymetry and Its Interpretation J.R
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ARCTIC VOL 36,NO. 2 (JUNE 19831 P 121-142 Maps of the Arctic Basin Sea Floor: A History of Bathymetry and its Interpretation J.R. WEBER' Contribution of the Earth Physics Branch No. 1045; LOREX Contribution No. 13 ABSTRACT. The history of oceanographic exploration of the Arctic Ocean basin from the beginning of this centur to the present is summarized. Soviet, U.S. and Canadian contributions after World War II are described in some detail including sounding methodsY and navigational techniques. The major bathymetric charts of the Arctic Ocean basin from 1954 on are discussed. Comparison of'the LOREX bathymetricmap with other maps reveals that the Lomonosov Ridge is accurately positioned on early Soviet maps but is grossly in error on later U.S. and Canadian maps. It is shown that map makers relied too much on early U.S. submarine data (the only such data that were declassified) and that the latest General Bathymetric Map of the Oceans (GEBCO) is therefore suspect of being inaccurate in areas where publicly available sounding data are scant. Key words: Arctic Ocean basin, bathymetry, Lomonosov Ridge, LOREX RÉSUMÉ. Un resum6 de l'historique de l'exploration du bassin octanique arctique depuis le dCbut du sikcle est prtsentt. Les contributions sovitt- iques, amtricaines et canadiennes depuisla deuxitme guerre mondiale sont dtcrites avec quelques dttails incluant des mtthodes de sondage et des techniques de navigation. Les cartes bathymttriques principales du bassin octanique hises depuis 1954 sont discuttes. La comparaison de la carte bathyrnktrique Ctablie par LOREX avec d'autres cartes montre que l'emplacement de la dorsale de Lomonosov est exact sur les premihres cartes établies par les Sovittiques, alorsqu'il est erron6 sur les cartes amhicaines et canadiennesplus rtcentes. II est dtmontrt que les cartographes sesont trop fits sur les premitres donntes sous-marinesanldricaines (les seules donntes accessibles au public) et que, par conséquent,les donntes de la der- nihre Cdition de la carte bathymttrique gtntrale des octans (GEBCO)peuvent &re inexactes dans les rtgions où les rtsultats de sondages accessibles au public sont peu abondants. Mots clCs: bassin octanique arctique, mesures bathymttrique, la dorsale de Lomonosov, LOREX Traduit par P. Morel, dtpartement de I'energie, mines et ressources. INTRODUCTION expeditions. Although the last ice island occupied by the U .S. For almost sixty years after the Fram drifted across the polar was abandoned in 1974, springtime airborne operations are sea it was believed that the Arctic Ocean abyssal plain con- still being carried out. In 1958 the Canadian Government sisted of one deep basin. The highly successful Soviet airborne created the Polar Continental Shelf Project (PCSP), an im- expedition tothe Pole of Relative Inaccessibility in 1941 aginative and very effective organization with a broad mandate neither proved nor disproved the one-basin concept, but it did to coordinate and support field activities in the Canadian High show that airplanes provided a practical and relatively inex- Arctic, which catapulted Canada to the forefront of polar pensive means of systematically exploring the Arctic Ocean research. Long-range planning permitted the systematic basin. After World War II the Soviets initiated two programs bathymetric and gravity mapping of the Canadian Arctic con- of data collection in the Arctic Ocean: the High Latitude Air- tinental shelf. PCSP supported two small-scale airborne ex- borne Expedition, whichtakes place every spring andwas peditions to the North Pole in 1967 and 1969, the forerunners designated NORTH-series, and the more permanent NORTH of the much larger multidisciplinary Lomonosov Ridge Ex- POLE-series whichis maintained for two to several years. periment in 1979 (LOREX 79). Both programs are still in operation today. In 1948 Soviet The first modern map that shows the ocean divided into two scientists found the Lomonosov Ridge but kept the discovery basins was published by the Soviets in 1954. With the excep- secret until 1954. In the early 1950s the United States started a tion of the chart compiled by the Canadian Defence Research program of airborne expeditions and occupations of ice Board in 1956 the early maps were all small-scale and ap- islands; from 1957 on these were complemented by submarine peared in scientific journals. Individual soundings were not 122 J.R. WEBER printed and the contouring reflected, to some extent, the com- The major sea-floor features of the Arctic Ocean and place piler’s personal bias in favour of a particular theory of evolu- names mentioned in the textare shown in Figure 1. The names tion of the ocean floor. By 1967 all the major physiological are those generally used today by Canadian geoscientists and features had been discovered, and the first official chart was correspond largely to the Bed et al. (1 966) and Treshnikov et compiled by the Canadian Hydrographic Service in prepara- ul. (1966) scheme of nomenclature which appears to be the tion for the first General Bathymetric Chart of the Oceans only scheme in which most of the terms have been approved (GEBCO) published the following year. During the next by the U.S. Board of Geographic Names and the International decade a British, a U.S. and a second Canadian chart were Hydrographic Bureau (Sweeney and Haines, 1978). Listed produced, followed, in 1979, by the second GEBCO chart. below are the names of submarine features used on U . S. maps The Soviets never produced any charts that were available to that differ from the nomenclature used in this text. the public. FIG. I. Overview map of Arctic Ocean with names used in text. Nomenclature of sea tloor features is that commonly uscd on Canadian maps and scientific papers. MAPS OF THE ARCTICBASIN SEA FLOOR 123 Canadian nomenclature U.S. nomenclature he drifted with the pack ice betweenlatitudes 72 “45’ and 74“N Nansen-Gakkel Ridge Arctic Mid Ocean Ridge and longitudes 145” to 150”W, taking numerous soundings Mid Arctic Ridge (map compiled by Geodetic Survey of Canada, in Stefansson, Nansen Ridge I92 1) , keeping meteorological records and taking celestial Mendeleev Ridge Mendeleyev Ridge Mendeleyev Ridge Mendeleev positions. Storkerson had planned to occupy the station for a Fram Basin Basin Amundsen year, buthe fell ill with asthma andwas forced to return B asin Fletcher Abyssal Plain Abyssal MakarovFletcher Basin prematurely to Flaxman Islandwhich he reached on 8 Basin Barents Abyssal Plain Abyssal BarentsNansen Basin November. During the whole drifting period the party of 5 menand 17 dogs lived entirely “off the land”, eating ex- The methodology of early Soviet hydrographic surveys, a clusively seal and bear meat and cooking and heating with seal description of Soviet aircraft types mentioned in the text, and a blubber and bear fat. Storkerson had no doubt that they could list of acronyms have been included in the Appendices. survive on the ice indefinitely by hunting. There is every in- dication that their ice floe was, in fact, a tabular iceberg of the HYDROGRAPHIC EXPLORATIONS EARLY type which is now called an ice island. Storkerson mentions From the Middle Ages until the end of the nineteenth cen- (Stefansson, 1921:699) that their floe could best be described tury geographers believed that the North Pole was surrounded as a large island, seven miles wide by at least 15 miles long by land or by an archipelago of islands. This concept lost and, judging from the freeboard near their camps, 50-60.feet credibility after Nansen’s ship Frum drifted withthe arctic thick. It moved at a different speed from the surrounding field pack ice from the New Siberian Islands to Svalbard between of smaller floes, and apparently it never broke up during the 1893 and 1896 (Nansen, 1897). It was found that the ocean entire six months they lived onit. Healso comments on the ap- along the entire length of Fram’s drift path was more than pearance of the “land” whichreminded him of certain 3000 m deep. This led many geographers to believe that the stretches of prairie. Storkerson’s was the prototype scientific whole Arctic Ocean basin wasa single oceanic deep, although, drifting station, antedating theRussian explorerPapanin’s based on analysis of tidal data alone, Harris (1904) postulated North Pole drift by 19 years. that it was divided by a barrier or ridge into two basins with With Stefansson’s expeditions the first phase of Canada’s different periods of oscillation. exploration of the Polar Sea came to an end. Robert Borden, During the first decade of the twentieth century Bob Bartlett, prime minister of Canada during the First World War, was a supporting Peary’s attemptson the North Pole, made a number staunch supporter of Stefansson. On his retirement in 1920 he of soundings off the northern coast of Ellesmere Island that was succeededby Arthur Meighen whothe following year was outlined the general shape of part of its continental shelf. defeated by the Liberals under MackenzieKing. The King One ofthe goals ofthe government-sponsored Canadian government had little interest in Canada’s Arctic, and nearly Arctic Expedition 19 13-1918 under the command of Vilhjal- forty years slipped away before the exploration of Canada’s mur Stefansson was to chart the waters of the Beaufort Sea arctic coastal waters was seriously resumed. north of Mackenzie Delta and BanksIsland. Stefansson’s ship, In 1927 Sir Hubert Wilkins, flying from Alaska, landed his the Karluk, became beset in the pack ice near Flaxman Island, aircraft on the ice some 1300km north of Bering Strait. By set- Alaska, For five months the Karluk drifted west until she was ting off an explosive chargeand using a stop watch to measure crushed near Wrangel Island on 10 January 1914; during that the time it took for the echo to return from the ocean floor, he timethe expedition’s oceanographer,James Murray, in- obtained a depth of 5440 m (Wilkins, 1928).