Swedish Deep-Sea Expedition Research Articles

Ueber Suesswasserdiatomeen in Atlantischen Tiefseesedimenten: Vorläufige mitteilung

One of the most remarkable features of the deep-sea sediment cores collected by the Swedish Deep-Sea Expedition is the presence of fresh-water diatoms. Every level of the off-shore diatomiferous cores examined so far contained a considerable amount of fresh-water forms, chiefly Melosira granulata and M. ambigua. The frequency in some instances was more than 1,000 frustules per slide (max. 1,900 frustules per slide). One level contained fresh-water species only. Another interesting fact was the frequent occurrence of silicified epidermal cells belonging to Cyperaceae or Gramineae.

The Swedish deep-sea expedition, 1947-48

ALTHOUGH Sweden has been active in oceanography for nearly a century, Swedish efforts were mainly concentrated within Scandinavian waters and to the relatively moderate depths there met with. Nevertheless, these studies led to an international co-operation the International Council for Sea investigations set up at the beginning of this century on Swedish initiative (OTTO PETTERSSON et. al.). With the outbreak of the Second World War Swedish activities at sea were severely limited, mainly to the fjords and the territorial waters immediately outside these. On the other hand, thanks largely to the munificience of priwtte donors, in GSteborg, and in Stockholm, Swedish oceanographers in the decade preceding the war had been provided with excellent institutions and other resources for laboratory work in the science of the sea, like Born5 Station on the Gullmarfjord, already founded in 1902 as a privately-owned research station, but acquired by the Swedish Government thanks to private donations in 1935, the Oceanografiska Institute in GSteborg bequeathed to the Royal Society in GSteborg by the Wallenberg Foundation and inaugurated in the beginning of 1939. Moreover, in 1930 a chair in oceanography had been founded at the University of GSteborg by private donors. With these resources Swedish oceanographers, during the enforced inactivity of the Second World War, seized the opportunity for constructing and testing new instruments and other implements of deep-sea research and for planning a circumnavigating deep-sea cruise, from which the new technique was to be utilized, as soon as the cessation of hostilities at sea permitted. In 1946 the Government research vessel, the Skagerak, was put at our disposal for a test cruise of 21⁄2 months duration to the Western Mediterranian, during which the new equipment was to be tried out in depths considerably greater than those accessible within Scandinavian waters (PETTERSSON 1947a). Besides the Swedish technique we also had on board the Skagerak a new recording echograph for great depths, constructed for us by the well-known London firm, Henry Hughes & Son (Marine Instruments Co.). The results from this experimental cruise gave excellent promise for the coming enterprise in the open oceans, and at the same time gave valuable information for various reconstructions, increasing the efficiency and the reliability of the new gear. The great problem of obtaining a research ship of the capacity necessary for a deep-sea cruise of 15 months was solved, thanks to the generosity of a Swedish shipping concern, BrostrSm & Co., in GSteborg, in giving us the loan of their new training ship, the 1,450 tons motor-schooner Albatross, and at the same time giving us permission to establish in the holds and other cargo-space of the ship our laboratories and accommodation for a scientific staff of l0 to 12, all air-conditioned for work in the tropics. * cf. H. PETIERSSON : A Swedish Deep-Sea Expedition. Proc. Roy. Soc., B, 134, 400 (1947).

The Tyndall Effect of Uniform Minerogenic Suspensions

The distribution of matter suspended in ocean water was stucGed during the Swedish Deep-sea Expedition be measuring the Tyndall effect in water samples (JERLOV, 1953). The scattering, s km -1 , caused by particles in suspension was computed. DOI: 10.1111/j.2153-3490.1953.tb01059.x

Vertical Distribution of Radium in Deep-Sea Sediments

THE surprisingly high content of radium in certain deep-sea sediments discovered nearly fifty years ago by J. Joly1 remained unexplained until 1937, when H. Pettersson2 suggested an ocean-wide precipitation of ionium from sea water on to the ocean bottom as its origin. Extensive radium measurements on deep-sea cores raised by the Swedish Deep-Sea Expedition carried out in this institute by Pettersson3, T. Bernert4 and me did not confirm the regular vertical distribution of radium reported by other workers5. An expected rise in radium content from moderate values in the uppermost surface layers to a maximum corresponding to a radioactive equilibrium between precipitated ionium and ionium-supported radium generally occurred; but the maximum was not followed by the theoretical exponential decline downwards governed by the rate of decay of ionium, to 50 per cent in 83,000 years, to 25 per cent in 166,000 years, etc. Instead, a number of secondary maxima of radium content separated by equally pronounced minima were observed (see graph), which could not well be explained as due to intervening changes in the rate of total sedimentation. Another explanation offered was that ionium and radium are not in radioactive equilibrium; that is, the assumption underlying the use of measurements of radium as indicating the concentration in the same layer of its mother element is unjustified.

Thorium Determination in Deep-Sea Sediments

MEASUREMENTS carried out in the Oceanographical Institute, Goteborg, on the radium content in deep-sea cores by H. Pettersson, Traude Bernert, V. Kroll1 et al. showed the vertical distribution of radium to be highly complicated. We were therefore asked to develop a method for direct measurement of the ionium content in samples of sediment from the Swedish Deep-Sea Expedition.

Studies of the Equatorial Currents in the Pacific

Some dynamic results have been derived from oceanographic data collected in the equatorial currents in the Pacific Ocean during the Swedish Deep Sea Expedition. Horizontal current velocities geostrophically computed for three meridional sections bring out some characteristic features in the flow distribution within the Countercurrent. A survey of the mass transport of water from surface to 500 m depth reveals a slow eastward flow at 12°–15° N. The reality of this weak additional countercurrent is, however, not clearly established.

North Atlantic Core Foraminifera Collected by Swedish Deep-Sea Expedition: ABSTRACT

Foraminifera have been studied from 39 long deep-sea cores and from 53 undisturbed surface sediment samples collected from the North Atlantic. Mid-latitude and low-latitude planktonic assemblages can be differentiated, with at least five different distribution types. The long cores contain faunas normal for their latitude alternating with faunas typical of higher latitudes. These are suggested as representing alternating cold and warm epochs, mostly Pleistocene; correlation of these epochs appears possible in a mid-latitude series of cores. Several cores contain shallow-water Foraminifera which have been displaced from shallow water. It is suggested that much of the mud in the deep ocean may be the finer fraction of sediments displaced from shallow water. Four cores contain planktonic Foraminifera of Miocene age. There is abundant evidence of solution of calcium carbonate; it is suggested that most of this solution occurred at the sediment surface and is related to the rate of production of Foraminifera. A mixed high and low latitude planktonic fauna occurring off Africa between 15° and 20° N. Lat. is attributed to mixing at the convergence of the Equatorial Counter Current and the Canaries Current. Mixed planktonic faunas occur in lower sections of cores off Africa between 0° and 7° N. Lat.; this suggests that the convergence area was displaced southward during the past. End_of_Article - Last_Page 188------------

The Tyndall Effect of Uniform Minerogenic Suspensions

The distribution of matter suspended in ocean water was studied during the Swedish Deep-sea Expedition be measuring the Tyndall effect in water samples (JERLOV, 1953). The scattering, s km–1, caused by particles in suspension was computed.

Replacement of Plagioclase by Orthoclase in Deep-Sea Deposits

IT is well known that authigenic orthoclase is present in fossil sediments of marine origin. In the course of my studies of fragments from gabbro and anorthosites in a core taken in 1948 by the Swedish Deep-Sea Expedition with the Albatross in the north-western Atlantic Ocean (lat. N. 29° 21′; long. W. 58° 59′; depth 5,450 m.), replacement of plagioclase (60–80 per cent anorthite) by authigenic orthoclase could be proved to have occurred. The replacement starts along fissures in the plagioclase. In fact, all stages in the transformation from fresh plagioclase to complete orthoclase were observed.

Sedimentation in the Tropical Indian Ocean

As a result of recent investigations1 into the distribution of the Radiolaria in the sediments collected by the Swedish Deep-Sea Expedition in the Western Pacific Ocean, two conclusions of outstanding importance can be drawn: first, that several species of Radiolaria which are widely distributed in the tropical oceans of the present day do not extend farther back in time than the very latest Tertiary or early Quaternary; secondly, that erosion and re-distribution of older sediments on the deep-sea floor often result in the mixing of the tests of Tertiary Radiolaria with Recent ones in that region.

The Philippine Trench and its Bottom Fauna

VERY little is known about animal life in the greatest ocean depths; only two previous hauls seem to have been made below 6,000 metres. In 1899 the U.S. Fish Commission steamer Albatross obtained siliceous sponges in the Tonga Trench at 4,173 fm. or 7,632 metres1. A similar deep haul was not made until 1948 when the Swedish Deep Sea Expedition trawled holothurians, a fragment of a polychaete, an isopod and a few amphipods in the Porto Rico Trench at depths between 7,625 and 7,900 metres2. I can, now report that in July the Danish Deep Sea Expedition of 1950–52 in the research ship Galathea obtained living animals of several phyla from a depth of greater than 10,000 metres in the Philippine Trench, more than 2,000 metres below previous known occurrences.

International Co-Operation in the Analyses of the Deep-Sea Cores Collected by the Swedish Deep-Sea Expedition 1947–48

International Co-Operation in the Analyses of the Deep-Sea Cores Collected by the Swedish Deep-Sea Expedition 1947–48

A new sedimentary petrological interpretation of the results reported by the Swedish "Albatross" deep-sea expedition, 1947-1948

Discusses the correlation of geophysical data obtained during the Swedish deep-sea expedition with sedimentary petrologic data, with special reference to the recognition of various stages of induration of the bottom sediments. The low values of reflected waves in sediments of the Indian and Pacific oceans are attributed to the presence of dolomite layers rather than lava beds.

Number of Radiolaria in sediments.

THROUGH the courtesy of Dr. B. Kullenberg, who is in charge of the study of the sediment cores from the Indian Ocean taken by him with the aid of his revolutionary sampler during the Swedish Deep-Sea Expedition, I have been able to examine several of the cores from that Ocean for microfossils. These investigations have been mainly restricted to the Radiolaria, and on this subject there is considerable disparity between our results and those of the John Murray Expedition to the same area. As this lack of agreement involves the matter of the technique of investigation of the biological components of deepsea sediments, it is considered advisable to publish a short notice before the appearance of the complete reports of the Expedition.

Nickel content of deep-sea deposits.

INVESTIGATIONS made in this Institute of the ferrides present in sediment cores from great depths, taken by the Swedish Deep-Sea Expedition, have shown their content of nickel to be specially interesting. The only analysis of nickel in deep-sea deposits known to us was published in 1914 by F. W. Clarke and G. Steiger, and gave 0.032 per cent as the content of nickel oxide in a composite sample of red clay from fifty-one different localities1. By the aid of modern microanalytical methods (the colour reaction with dimethyl glyoxime) quantities of nickel as small as 5–6 γ can easily be measured.

Ultra-violet radiation in the sea.

DURING the Swedish Deep-Sea Expedition with the Albatross, measurements of sub-surface radiation were carried out in different areas, chiefly by means of photo-electric methods. Special attention was given to the study of the biologically important short-wave part of the spectrum. The range beyond 315 mµ with anti-rachitic effects was determined by means of a special technique. Two liquid filters, namely, 18 mm. saturated nickel sulphate solution and 14 mm. picric acid solution (45 mgm. per litre), are used, together with a 6-mm. UG5 glass from Schott und Genossen. These filters are combined with a selenium rectifier cell adapted for the ultra-violet, the liquids being enclosed between three concentric hemispherical quartz shells around the cell covered by the UG5 glass. The centre of gravity for the measured radiation is estimated at 310 mµ. The photometer is connected to an Ising galvanometer with a sensitivity of 4 × 10−10 amp. per scale unit.

Heat-Flow Below the Oceans

PROF. HANS PETTERSSON has reported1 measuring the geothermal gradient at two places in the deep-sea sediment below the Pacific Ocean. This work, done from the schooner Albatross of the first Swedish Deep-Sea Expedition, is apparently the first of its kind and is an important contribution to the study of the heat flowing from the interior of the earth.

The Swedish Deep Sea Expedition. The Geological Material and its Treatment with special Regard to the Eastern Pacific

(1950). The Swedish Deep Sea Expedition. The Geological Material and its Treatment with special Regard to the Eastern Pacific. Geologiska Foreningen i Stockholm Forhandlingar: Vol. 72, No. 2, pp. 185-191.

Preliminary Results from the Study of an Ocean Core Obtained by the Swedish Deep-Sea Expedition, 1947–48

Preliminary Results from the Study of an Ocean Core Obtained by the Swedish Deep-Sea Expedition, 1947–48

Preliminary Results from the Study of an Ocean Core Obtained by the Swedish Deep-Sea Expedition, 1947–48

Preliminary Results from the Study of an Ocean Core Obtained by the Swedish Deep-Sea Expedition, 1947–48