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1.
H. Pettersson 《Meteorology and Atmospheric Physics》1954,7(1):477-481
Zusammenfassung Der Verfasser, der seit mehr als 30 Jahren die Tiefseesedimente und insbesondere den Roten Ton untersucht, ist namentlich auf Grund der Ergebnisse der Schwedischen Tiefsee-Expedition mit der Albatross zur Überzeugung gelangt, daß die landläufige Erklärung für das Verschwinden des Kalks, dank dessen es zur Bildung des Roten Tones kommt, nicht genügt. Die Bildung desselben während des Tertiärs darf nicht der Wirkung kalter antarktischer und arktischer Grundströmungen zugeschrieben werden; diese werden im Gegenteil sehr schwach gewesen sein oder gar nicht existiert haben, da es damals keine polaren Eiskappen gab und die Bodentemperatur der Ozeane um 8 bis 10° C höher war als heute. Viel eher kommen für die Bildung des Roten, Tones magmatische Gase wie CO2, HCl usw. als wichtigste Kalklöser in Betracht, die zu der Zeit ausgeworfen wurden, als submarine Vulkanausbrüche oder Extrusionen von Tiefenmaterial zur Bildung des mittelatlantischen Rückens und anderer submariner Gebirgszüge geführt haben.
Summary The author who for over 30 years has studied deep-sea sediments and especially the Red clay has, especially on basis of results from the Swedish Deep-Sea Expedition with the Albatross, arrived at the conviction that the current explanation for the disappearance of the lime leading to the formation of Red clay is not sufficient. The formation of Red clay during Tertiary time cannot be ascribed to the action of cold Antarctic and Arctic bottom currents, which must have been very feeble or missing, when there were no polar ice-caps and the bottom temperature of the oceans was about 8° to 10° higher than at present. A principal lime-dissolving agency, responsible for the formation of Red clay are magmatic volatiles, i.e. carbon dioxide, hydrochloric acid etc., released at submarine volcanic eruptions or at the extrusion of subcrustal matter, leading to the formation of the Madatlantic Ridge and other submarine ridges.
Résumé L'auteur qui, depuis plus de 30 années, étudie les sédiments abyssaux et, en particulier, les argiles rouges, est convaincu, et cela notamment depuis l'expédition océanographique suédoise de «Albatross», que l'explication courante de la disparition du calcaire qui conduit à la formation de cette argile n'est pas suffisante. Pendant la période tertiaire, on ne peut pas en attribuer la formation à l'action, de courants très froids arctiques et antarctiques parcourant le fonds des océans, car ceux-ci durent être très faibles, voire inexistants si l'on admet que les calottes glaciaires des pôles n'existaient pas et que la température abyssale était supérieure de 8° à 10° C à celle d'aujourd'hui. Le principal agent solvant du calcaire à l'origine des argiles rouges doit être reconnu dans certaines volatilisations du magma, tels le dioxyde de carbone et l'acide chlorhydrique par exemple. Celles-ci doivent avoir été provoquées par des éruptions volcaniques sous-marines ou par des extrusions de matériaux volcaniques qui ont conduit à la formation de nombreuses chaînes de montagnes sous-marines comme par exemple celle du centre de l'Atlantique.相似文献
2.
Pettersson M Hahlbeck E Katsiadaki I Asplund L Bengtsson BE 《Marine pollution bulletin》2007,54(12):1868-1880
The potential for endocrine disruption close to sewage treatment plant and pulp mill effluent discharge points along the Swedish Baltic Sea coast was explored using a dual survey strategy employing two stationary fish species. The levels of vitellogenin and spiggin as biomarkers of endocrine disruption were determined in juvenile three-spined sticklebacks (Gasterosteus aculeatus L.) together with the sex ratios and the presence of intersex. As an indication of exposure, estrogenic and androgenic substances were analysed by GC–MS in bile from perch (Perca fluviatilis L.). Spiggin and vitellogenin levels in juvenile three-spined sticklebacks were generally low, and, for most sampling sites no deviation in gonad type ratios were observed. No remarkable levels of natural or synthetic estrogens or androgens were observed in bile fluid from perch, while bisphenol A and 4-nonylphenol were detected in perch from both reference sites and exposed sites. Taken together, the results did not indicate estrogenic or androgenic disruption in the investigated waters. 相似文献
3.
H. E. Fossum B. A. Pettersson Reif M. Tutkun T. Gjesdal 《Boundary-Layer Meteorology》2012,144(1):21-40
Aerosol dispersion in the area surrounding an existing biological treatment facility is investigated using large-eddy simulation,
with the objective to investigate the applicability of computational fluid dynamics to complex real-life problems. The aerosol
sources consist of two large aeration ponds that slowly diffuse aerosols into the atmosphere. These sources are modelled as
dilute concentrations of a non-buoyant non-reacting pollutant diffusing from two horizontal surfaces. The time frame of the
aerosol release is restricted to the order of minutes, justifying a statistically steady inlet boundary condition. The numerical
results are compared to wind-tunnel experiments for validation. The wind-tunnel flow characteristics resemble neutral atmospheric
conditions with a Reynolds number, based on the boundary-layer thickness, of Re
δ
≈ 2 × 105. The numerical inflow conditions are based upon the wind-tunnel flow field. The predicted decay of both the mean and root-mean-square
concentrations are in good agreement with experimental data; at 3 m from the ground, the plume mean concentration 200 m downwind
of the source is approximately 2% of the source strength. The numerical data in the near-surface layer (0–50 m from the ground)
correspond particularly well with the wind-tunnel data. Tentative deposition simulations suggest that there seems to be little
difference in the deposition rates of large (1.8 × 10−5 m) and small (3 × 10−6 m) particles in the near-field under the flow conditions considered. 相似文献
4.
P. P. Povinec I. Osvath M. S. Baxter S. Ballestra J. Carroll J. Gastaud I. Harms L. Huynh-Ngoc L. Liong Wee Kwong H. Pettersson 《Marine pollution bulletin》1997,35(7-12):235-241
IAEA-MEL participated in five expeditions to the Kara Sea with the aim of assessing the radiological consequences of dumped radioactive wastes in the Novaya Zemlya Bays and Trough. The programme included sampling, in-situ underwater investigations, laboratory analyses of water, sediment and biota samples, the development of a marine radioactivity database, modelling and radiological assessment, the organization of intercomparison exercises and the evaluation of distribution coefficients. Radiometric investigations have shown that no radiologically significant environmental contamination has occurred. Leakages which have led to locally increased levels of radionuclides in sediment have only been observed in Stepovoy and Abrosimov Bays. Computer modelling results suggest that only radiological effects on local and regional scales may be of importance. The global radiological impact of the disposals in the Arctic Seas will be negligible. 相似文献
5.
6.
The growth of young waves along a narrow bay and their directional spectra were studied. The fetch geometry was found to affect the shape of the spectrum already when the waves were young. When compared to the growth from a straight shoreline, the dimensionless energy was reduced, but the change in dimensionless peak frequency was smaller. The behaviour of the young waves was similar to that of the mature waves but the differences between narrow and broad fetch geometries were smaller, which suggests that due to a stronger nonlinear transfer the young waves are less sensitive to the fetch geometry. The directional spectrum of the young waves in the narrow fetch geometry was narrower at all energy containing frequencies than the spectra from broad fetch geometry, which further supports the conclusion that the shape of the spectrum is not independent of the fetch geometry. 相似文献
7.
Seasonal dynamics of a cyanobacteria-dominated microbial community in surface sediments of a shallow,eutrophic lake 总被引：16，自引：0，他引：16
Bengt Boström Anna-Kristina Pettersson Ingemar Ahlgren 《Aquatic Sciences - Research Across Boundaries》1989,51(2):153-178
The seasonal variation of microbial biomass and activity in the surface sediments (0–10 cm) of the shallow, eutrophic Lake Vallentunasjön was followed during one year. OverwinteringMicrocystis colonies dominated the microbial community during all seasons, constituting 60–90% of the total microbial biomass. Expressed on an areal basis, the benthic biomass was, throughout the year, larger than or similar to the planktonic biomass during the peak of the summer bloom, indicating an ability of the colonies to survive in the sediments for extended periods. Abundance of other, non-photosynthetic bacteria varied in the range 3.0–15.5 · 1010 cells g–1 d. w. over the year with minimum values in summer and maximum values in autumn in connection with the sedimentation of theMicrocystis bloom. A substantial part of the non-photosynthetic bacteria, up to circa 40%, was associated with the mucilage of healthyMicrocystis colonies. Bacterial production (3H-thymidine incorporation) appeared to be strongly temperature dependent and less influenced by the seasonal sedimentation pattern. Our data indicate an increasing proportion of non-growing cells in autumn and winter. Biomass-bound phosphorus constituted a significant portion, circa 10%, of the phosphorus content in Lake Vallentunasjön sediments. This pool has normally been overlooked in studies on phosphorus dynamics in lake sediments. Different mechanisms whereby organic phosphorus can be released from the sediments are discussed. 相似文献
8.
Frequent sampling during an annual cycle of dissolved(<0.45 m) and suspended (>0.45 m) elementshas been conducted in the Kafue River at Raglan'sFarm, upstream from the mining activities within theCopperbelt Province, Zambia. Additional sampling ofsediment and interstitial pore water was conductedduring low water discharge. The presence of carbonateswithin the drainage basin naturally gives rise to highelement concentrations in the dissolved phase(Ca = 626, Mg = 494, Na = 360 and K = 24 mmol l-1).During the rainy season the relative composition ofthe dissolved elements indicated a wash out ofaccumulated weathering products and mineralisedorganic material from the unsaturated zone of the soilprofile. High concentrations of dissolved Al, Fe andMn were measured during high water discharge. At lowwater discharge the sediment was a major source of Fe,Mn and associated Co and Cu to the water column.Enhanced concentrations of dissolved and suspended S,Co and Cu during the rainy season indicated thatatmospheric deposited particles from the mining areawere washed out into the river. Autochthonousformation of particles rich in Si indicated diatomproduction during low water discharge. 相似文献
9.
Neil F. Glasser Michael J. Hambrey James L. Etienne Peter Jansson Rickard Pettersson 《Geografiska Annaler: Series A, Physical Geography》2003,85(2):127-147
Storglaciären is a 3.2 km long polythermal valley glacier in northern Sweden. Since 1994 a number of small (1–2 m high) transverse debris‐charged ridges have emerged at the ice surface in the terminal zone of the glacier. This paper presents the results of a combined structural glaciological, isotopic, sedimentological and ground‐penetrating radar (GPR) study of the terminal area of the glacier with the aim of understanding the evolution of these debris‐charged ridges, features which are typical of many polythermal glaciers. The ridges originate from steeply dipping (50–70°) curvilinear fractures on the glacier surface. Here, the fractures contain bands of sediment‐rich ice between 0.2 and 0.4 m thick composed of sandy gravel and diamicton, interpreted as glaciofluvial and basal glacial material, respectively. Structural mapping of the glacier from aerial photography demonstrates that the curvilinear fractures cannot be traced up‐glacier into pre‐existing structures visible at the glacier surface such as crevasses or crevasse traces. These curvilinear fractures are therefore interpreted as new features formed near the glacier snout. Ice adjacent to these fractures shows complex folding, partly defined by variations in ice facies, and partly by disseminated sediment. The isotopic composition (δ18O) of both coarse‐clear and coarse‐bubbly glacier ice facies is similar to the isotopic composition of the interstitial ice in debris layers that forms the debris‐charged ridges, implying that none of these facies have undergone any significant isotopic fractionation by the incomplete freezing of available water. The GPR survey shows strong internal reflections within the ice beneath the debris‐charged ridges, interpreted as debris layers within the glacier. Overall, the morphology and distribution of the fractures indicate an origin by compressional glaciotectonics near the snout, either at the thermal boundary, where active temperate glacier ice is being thrust over cold stagnant ice near the snout, or as a result of large‐scale recumbent folding in the glacier. Further work is required to elucidate the precise role of each of these mechanisms in elevating the basal glacial and glaciofluvial material to the ice surface. 相似文献
10.
Hall Sarah Pettersson Jessica Meservy William Harris Ron Agustinawati Diannitta Olson Jennie McFarlane Allayna 《Natural Hazards》2017,89(1):473-496
Natural Hazards - The south coast of Java has a long history of deadly seismogenic tsunamis. The most recent tsunami events in 1994 and 2006 killed hundreds due to lack of awareness and... 相似文献