Sample records for fiords
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Preliminary bathymetry of Northwestern Fiord and Neoglacial changes of Northwestern Glacier
Post, Austin
1980-01-01
The first preliminary bathymetry (at 1:20,000 scale) and other scientific investigations of Northwestern Fiord, Alaska, were conducted by the Research Vessel Growler in 1978, disclosing this 10.5-mile-long branched waterway to be a deep basin enclosed by a terminal-moraine shoal. The basin was formerly filled by Northwestern Glacier, which began a drastic retreat around 1909 and reached the head of the main arm around 1960. Soundings and profiles show the main channel to be as much as 970 feet deep and to have the typical U shape of a severely glacially eroded valley; since the glacier 's retreat, sediments have formed nearly level deposits in the deepest reaches, while the rest of the basin has a hard, rocky bottom. Preneoglacial forest debris dated by carbon-14 indicates Northwestern Glacier to have advanced into the fiord prior to 1,385 years before present (B.P.); a branch glacier evidently advanced into forest 1,635 years B.P. The combined glaciers from several arms culminated on the present terminal-moraine shoal around 1894. (USGS)
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Evaluation of faba beans ( Vicia faba cv. Fiord) and sweet lupins ...
African Journals Online (AJOL)
Evaluation of faba beans ( Vicia faba cv. Fiord) and sweet lupins ( Lupizus albus cv. Kiev) as protein sources for ... P igsi n the metabolisrna ndN balance trial consurned5 % less( P < 0.01)o 1'thel upind ietc omparedto the fabab eand iet (l 370 vs. | 440 gld).N o significandt ift'erenceisn the digestiblee nergy( DE) contenta nd ...
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O Uso da Sísmica de Reflexão nos Estudos de Geomorfologia Submarina em Fiordes, Chile
Directory of Open Access Journals (Sweden)
Rosemary Vieira
2004-12-01
Full Text Available Este trabalho apresenta resultados do uso da sísmica de reflexão sísmica em ambientes deposicionais glaciomarinhos da costa de fiordes norte e central do Chile. As geoformas são identificadas de acordo com as distintas respostas dos refletores acústicos, através do perfilador de subfundo 3.5 kHz. Facies sísmicas e movimentos de massa distribuídos ao longo dos fiordes de irregular morfologia submarina são classificados e interpretados em conjunto com modelos 3D da topografia submarina e subaérea, além de mapas de pendentes. Apesar de ser um importante instrumento para a reconstrução de paleoambientes glaciomarinhos, a sísmica de reflexão apresenta limitações quando não dispõe de amostras sedimentológicas in situ.
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Resonancias de la ficción: Una lectura post-política de El fiord, de Osvaldo Lamborghini.
Directory of Open Access Journals (Sweden)
Mario Aznar Pérez
2016-12-01
Full Text Available Este trabajo plantea una aproximación a El fiord (1969, del autor argentino Osvaldo Lamborghini, desde la óptica contemporánea del lector post-político. Entendiendo este último concepto como espacio epistémico y no como una mera estrategia política, nos preguntamos: ¿qué queda de un texto marcadamente ideológico cuando es leído desde una sociedad sin ideologías? ¿Puede el contenido político de un texto literario mantener su vigencia en el tiempo? Para tratar de responder a estas cuestiones proponemos la revisión de algunos conceptos importantes como son el de «literatura política» o el de «transgresión», a la luz de una teoría del texto orgánica y en constante movimiento
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Sedimentology and geomorphology of a large tsunamigenic landslide, Taan Fiord, Alaska
Dufresne, A.; Geertsema, M.; Shugar, D. H.; Koppes, M.; Higman, B.; Haeussler, P. J.; Stark, C.; Venditti, J. G.; Bonno, D.; Larsen, C.; Gulick, S. P. S.; McCall, N.; Walton, M.; Loso, M. G.; Willis, M. J.
2018-02-01
On 17 October 2015, a landslide of roughly 60 × 106 m3 occurred at the terminus of Tyndall Glacier in Taan Fiord, southeastern Alaska. It caused a tsunami that inundated an area over 20 km2, whereas the landslide debris itself deposited within a much smaller area of approximately 2 km2. It is a unique event in that the landslide debris was deposited into three very different environments: on the glacier surface, on land, and in the marine waters of the fjord. Part of the debris traversed the width of the fjord and re-emerged onto land, depositing coherent hummocks with preserved source stratigraphy on an alluvial fan and adjacent moraines on the far side of the fjord. Imagery from before the landslide shows that the catastrophic slope failure was preceded by deformation and sliding for at least the two decades since the glacier retreated to its current terminus location, exposing steep and extensively faulted slopes. A small volume of the total slide mass remains within the source area and is topped by striated blocks (> 10 m across) and standing trees that were transported down the slope in intact positions during the landslide. Field work was carried out in the summer of 2016, and by the time this paper was written, almost all of the supraglacial debris was advected into the fjord and half the subaerial hummocks were buried by glacial advance; this rapid change illustrates how highly active sedimentary processes in high-altitude glacial settings can skew any landslide-frequency analyses, and emphasizes the need for timely field investigations of these natural hazards.
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Elberling, Bo; Knudsen, Karen Luise; Kristensen, Peter H; Asmund, Gert
2003-04-01
Sulphidic mine waste disposed in marine environments constitutes an environmental risk to aquatic life due to potential uptake and accumulation of heavy metals in biota. Fiord sediments near the former Black Angel Mine in West Greenland are contaminated by lead and zinc as a result of submarine tailings disposal in 1973-1990. In 1999 cores were taken up to 10 km away from the disposal area. Analyses include heavy metals, radiochemical dating (210Pb) and high-resolution foraminiferal stratigraphy. The mining operation resulted in significant changes in the assemblage composition. In addition, up to 20% of the Melonis barleeanus population found in sediment deposited during nearby tailings disposal was deformed compared to a natural background of less than 5%. Throughout cores representing the last 100 years of sedimentation, the total numbers and frequency of morphological abnormalities among M. barleeanus revealed some correlation with heavy metals concentrations (up to r2 = 79%). We conclude that abnormalities among foraminifera may represent a useful biomarker for evaluating trends in the biological impact resulting of submarine tailings disposal as well as long-term environmental impact and subsequent recovery.
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Trabant, Dennis C.; March, Rod S.; Thomas, Donald S.
2003-01-01
Hubbard Glacier, the largest calving glacier on the North American Continent (25 percent larger than Rhode Island), advanced across the entrance to 35-mile-long Russell Fiord during June 2002, temporarily turning it into a lake. Hubbard Glacier has been advancing for more than 100 years and has twice closed the entrance to Russell Fiord during the last 16 years by squeezing and pushing submarine glacial sediments across the mouth of the fiord. Water flowing into the cutoff fiord from mountain streams and glacier melt causes the level of Russell Lake to rise. However, both the 1986 and 2002 dams failed before the lake altitude rose enough for water to spill over a low pass at the far end of the fiord and enter the Situk River drainage, a world-class sport and commercial fishery near Yakutat, Alaska.
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Energy Technology Data Exchange (ETDEWEB)
1983-01-01
This report presents the results of an environmental study carried out in the Qingua/Tunugliarfik Fiord area north of Narssarssuaq in July-October, 1982. The field work in the area included hydrographic investigations in the Tunugliarfik Fiord, fishery investigations in the Qingua river and a survey of the area likely to be affected by a hydro-electric plant. Information on commercial and sport fishing, hunting, sheep-farming, tourism, and conservation interests was also collected. The hydrographic investigations have shown that the inner part of Tunugliarfik is dominated by the estuarine circulation in the upper layer clearly influenced by the Qoroq Fiord. The lower 5 km of the river contain a large population of arctic char. The size of the migrating stock, i.e. excluding young and residual fish, is estimated at 10.000 - 20.000 fish. A series of waterfalls in the end of the Qingua valley constrains migrating fish to the lower river area. Beyond the falls two separate populations of stream-resident arctic char are found. Another non-migrant population is found in the Nordbo/Storesoe area. The arctic char fishery is locally of great importance. The fishery, which is carried out by use of gill net, is particularly extensive in the inner part of the Tunugliarfik Fiord. The Qiangua valley is also a popular site for anglers coming to the area by a daily boat from the hotel in Narssarssuaq. Besides char, great quantities of Greenland cod and Greenland halibut are caught in the fiord. The major part of the catch is consumed locally.
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Omelon, Christopher R.; Pollard, Wayne H.; Marion, Giles M.
2001-05-01
- Spring discharge at Expedition Fiord (Pollard et al., 1999) on Axel Heiberg Island in the Canadian High Arctic produces a variety of travertine forms in addition to a diverse collection of mineral precipitates. This paper focuses on clusters of thermally unstable crystals believed to be the mineral ikaite (CaCO 3 · 6H 2O) growing seasonally along two spring outflows at Colour Peak. This form of calcium carbonate mineral occurs along small sections of discharge outflow as white euhedral crystals up to 0.5 cm in length. Difficulty in sampling, storage and transport of the samples for analysis has hampered attempts to confirm the presence of ikaite by X-ray diffraction. However, various field observations and the remarkable instability of these crystals at normal ambient temperatures strengthens our argument. This paper provides a description of these particular CaCO 3 · 6H 2O crystals and their environmental surroundings, and attempts to determine the validity of ikaite precipitation at this site by theoretical geochemical modeling: these results are compared with other reported observations of ikaite to both understand their occurrence and help delineate their geochemical characteristics. It is believed that the restrictive combination of spring water chemistry and long periods of low temperatures characteristic of arctic climates are necessary for ikaite growth at this site. The fact that ikaite is not forming at a second group of saline springs 11 km away allows us to more specifically outline conditions controlling its presence.
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Coastal Erosion and Flooding Hazards on the North Sea Coast at Thyboron, Denmark
DEFF Research Database (Denmark)
Sørensen, Per; Sørensen, Carlo Sass; Nielsen, Peter
Since a breach of the coastal barrier in 1862, the Thyboron Channel connecting the North Sea and the Lim Fiord has been artificially maintained by construction of breakwaters and groins on the North Sea coast and inside the channel, respectively. Sand nourishment schemes have since the 1980s coun...... counteracted the natural erosion in the upper profile on the North Sea coast where the alongshore sediment transport converges towards the channel and deposits up to 1 million m3/y on the flood tidal delta inside the fiord, Figure 1.......Since a breach of the coastal barrier in 1862, the Thyboron Channel connecting the North Sea and the Lim Fiord has been artificially maintained by construction of breakwaters and groins on the North Sea coast and inside the channel, respectively. Sand nourishment schemes have since the 1980s...
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Wright, Katherine E; Williamson, Charles; Grasby, Stephen E; Spear, John R; Templeton, Alexis S
2013-01-01
We combined free enenergy calculations and metagenomic analyses of an elemental sulfur (S(0)) deposit on the surface of Borup Fiord Pass Glacier in the Canadian High Arctic to investigate whether the energy available from different redox reactions in an environment predicts microbial metabolism. Many S, C, Fe, As, Mn, and [Formula: see text] oxidation reactions were predicted to be energetically feasible in the deposit, and aerobic oxidation of S(0) was the most abundant chemical energy source. Small subunit ribosomal RNA (SSU rRNA) gene sequence data showed that the dominant phylotypes were Sulfurovum and Sulfuricurvum, both Epsilonproteobacteria known to be capable of sulfur lithotrophy. Sulfur redox genes were abundant in the metagenome, but sox genes were significantly more abundant than reverse dsr (dissimilatory sulfite reductase)genes. Interestingly, there appeared to be habitable niches that were unoccupied at the depth of genome coverage obtained. Photosynthesis and [Formula: see text] oxidation should both be energetically favorable, but we found few or no functional genes for oxygenic or anoxygenic photosynthesis, or for [Formula: see text] oxidation by either oxygen (nitrification) or nitrite (anammox). The free energy, SSU rRNA gene and quantitative functional gene data are all consistent with the hypothesis that sulfur-based chemolithoautotrophy by Epsilonproteobacteria (Sulfurovum and Sulfuricurvum) is the main form of primary productivity at this site, instead of photosynthesis. This is despite the presence of 24-h sunlight, and the fact that photosynthesis is not known to be inhibited by any of the environmental conditions present. This is the first time that Sulfurovum and Sulfuricurvum have been shown to dominate a sub-aerial environment, rather than anoxic or sulfidic settings. We also found that Flavobacteria dominate the surface of the sulfur deposits. We hypothesize that this aerobic heterotroph uses enough oxygen to create a microoxic
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Directory of Open Access Journals (Sweden)
Katherine E Wright
2013-04-01
Full Text Available We combined free energy calculations and metagenomic analyses of an elemental sulfur (S0 deposit on the surface of Borup Fiord Pass Glacier in the Canadian High Arctic to investigate whether the energy available from different redox reactions in an environment predicts microbial metabolism. Many S, C, Fe, As, Mn and NH4+ oxidation reactions were predicted to be energetically feasible in the deposit, and aerobic oxidation of S0 was the most abundant chemical energy source. Small subunit ribosomal RNA (SSU rRNA gene sequence data showed that the dominant phylotypes were Sulfurovum and Sulfuricurvum, both Epsilonproteobacteria known to be capable of sulfur lithotrophy. Sulfur redox genes were abundant in the metagenome, but sox genes were significantly more abundant than reverse dsr genes. Interestingly, there appeared to be habitable niches that were unoccupied at the depth of genome coverage obtained. Photosynthesis and NH4+ oxidation should both be energetically favorable, but we found few or no functional genes for oxygenic or anoxygenic photosynthesis, or for NH4+ oxidation by either oxygen (nitrification or nitrite (anammox. The free energy, SSU rRNA gene and quantitative functional gene data are all consistent with the hypothesis that sulfur-based chemolithoautotrophy by Epsilonproteobacteria (Sulfurovum and Sulfuricurvum is the main form of primary productivity at this site, instead of photosynthesis. This is despite the presence of 24-hour sunlight, and the fact that photosynthesis is not known to be inhibited by any of the environmental conditions present. This is the first time that Sulfurovum and Sulfuricurvum have been shown to dominate a sub-aerial environment, rather than anoxic or sulfidic settings. We also found that Flavobacteria dominate the surface of the sulfur deposits. We hypothesize that this aerobic heterotroph uses enough oxygen to create a microoxic environment in the sulfur below, where the Epsilonproteobacteria can
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Directory of Open Access Journals (Sweden)
Piotrowska Ewa
2017-12-01
Full Text Available This article discusses the operation of Norwegian libraries on the example of the National Library in Oslo, the Bergen University Library, and the Stavanger Public Library. A modern building of the Public Library in Vennesla is presented. Norwegian librarianship issues (librarians’ education, librarians’ associations, interlibrary loan, reading, as well as the Doomsday Library project are discussed.
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Continued pollution from mining at Maarmorilik
DEFF Research Database (Denmark)
Voigt, Steen
2008-01-01
Almost 20 years after the closure of the lead and zinc mine at Maarmorilik in the municipality of Uummannaq in North West Greenland pollution of surrounding fiords and land stretches with the metals continues, all though in a much lesser degree than earlier. This shows a new report by the Danish...
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African Journals Online (AJOL)
Evaluation of dehulled faba bean (Vicia faba cv. Fiord) as a protein source for laying hens. Abstract PDF · Vol 42, No 1 (2012) - Articles The performance of broilers on a feed depends on the feed protein content given previously. Abstract PDF · Vol 42, No 4 (2012) - Articles Broiler breeders utilise body lipid as an energy ...
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Energy Technology Data Exchange (ETDEWEB)
Landstroem, O; Samsahl, K; Wenner, C G
1967-10-15
A neutron activation method for multi-elemental analysis was applied to argillaceous deposits from the Viskan Valley on the Swedish West Coast, an area in which transgressions and regressions of the sea have occurred during the postglacial time. These changes between fresh-water and marine stages are well known from earlier geologic investigations. Analysis could therefore be performed of samples of known marine (brackish) and lacustrine origin. In a preliminary test on four samples, taken from two marine layers and two lacustrine layers, altogether 30 elements were quantitatively determined, namely As, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Ga, Hf, Hg, La, Lu, Mn, Na, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, W, Yb, Zn and Zr. Several elements showed a difference in concentration between the marine and the fresh-water layers. Br, Hg, Mn, Se, As and Sb were more thoroughly investigated in three boreholes from different sections of the valley. Br and Se had high means in the most pronounced marine samples of the fiord deposits. Moreover, Mn showed a fourfold increase just in the transition stage between the older sea fiord and the older lage stage.
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International Nuclear Information System (INIS)
Landstroem, O.; Samsahl, K.; Wenner, C.G.
1967-10-01
A neutron activation method for multi-elemental analysis was applied to argillaceous deposits from the Viskan Valley on the Swedish West Coast, an area in which transgressions and regressions of the sea have occurred during the postglacial time. These changes between fresh-water and marine stages are well known from earlier geologic investigations. Analysis could therefore be performed of samples of known marine (brackish) and lacustrine origin. In a preliminary test on four samples, taken from two marine layers and two lacustrine layers, altogether 30 elements were quantitatively determined, namely As, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Ga, Hf, Hg, La, Lu, Mn, Na, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, W, Yb, Zn and Zr. Several elements showed a difference in concentration between the marine and the fresh-water layers. Br, Hg, Mn, Se, As and Sb were more thoroughly investigated in three boreholes from different sections of the valley. Br and Se had high means in the most pronounced marine samples of the fiord deposits. Moreover, Mn showed a fourfold increase just in the transition stage between the older sea fiord and the older lage stage
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The need to be cold : cold warriors
Energy Technology Data Exchange (ETDEWEB)
Gregoire, L.
2008-10-15
This article discussed the changing climate of Ellesmere Island and the adaptation of the Inuit in response to the climate change, with particular reference to Canada's most northern community of Grise Fiord. Because of the changing climate, the vast northern landscape that the Inuit navigated for centuries by reading its subtle signs is becoming warmer, softer, and unpredictable. The geographic history and demographics of Grise Fiord were described. The community's main water supply comes from a glacier which is sinking. The negative impacts of ice shrinkage on this northern community and on the environment were presented. These included more international shipping through the Arctic, more resource exploration, a greater risk of environmental contamination, and reduced habitat for the polar bears and seals that eat, mate, and reproduce on the ice. Climate change impacts on the sea and sea ice were also discussed. Several photographs illustrating the changing climate were presented. The article noted that climate change could destroy the Inuit culture, making climate change an issue of human rights, notably the right to live connected to the land and the right to be cold. It was concluded that in one generation, Inuit were swept up by both a social and an economic upheaval. In one more generation, they will undergo an environmental shift. 13 figs.
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Geochemistry of sediments of the western Canadian continental shelf
Macdonald, R. W.; Pedersen, T. F.
1991-08-01
Few chemical data exist for the sedimentary environment off the Canadian west coast. Here we define the chemical nature of the shelf sediments by examining the important sources of material (natural and anthropogenic) to the region and processes relevant to diagenesis. Slightly more data exist for the continental shelf to the south (Washington) and north (Alaska), however it is clear that the sedimentary environment of these neighbouring shelves differs importantly from the Canadian portion. The British Columbia shelf receives little modern terrigenous detritus due mainly to isolation from terrestrial sediment sources by fiords, inland seas, or bypassing by shelf canyons. The chemical state of the sediments depends on the rate of supply of material, the energy of the depositional or erosional environment and the organic and inorganic composition of the material. These features in concert with bottom water characteristics control the redox state. Although no basins hosting continuous depositional records for the Holocene on the open British Columbia shelf have been identified or studied in a manner described by BUCKLEY ( Continental Shelf Research, 11, 1099-1122), some coastal embayments and fiords provide valuable historical records of post-glacial sedimentation. Such environments will prove to be increasingly useful in future studies of changes in regional climate and in establishing the chronology of natural disasters and anthropogenic impacts. Recommendations are given for a variety of research projects that would help us to understand better both chemical interactions at the seabed and Late Quaternary depositional history.
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Situk River Hydrology Following Closure of Russell Fiord by Hubbard Glacier
2011-03-01
approximately 137.2 ft. A HEC - RAS one-dimensional flow model estimated the levels and flows of the Si- tuk River system, including the Old Situk, Upper...23 Development of HEC - RAS geometry for Situk River ................................................................. 26 Boundary conditions...28 Figure 20. Situk River geometry model in HEC - RAS
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Nutritional evaluation of dehulled faba bean (Vicia faba cv. Fiord) in ...
African Journals Online (AJOL)
p2492989
Where a choice was offered between feeds containing soya and faba bean the ... An important question is whether the responses in food intake, growth or feed ..... that the slightly astringent taste of condensed tannins increases palatability and.
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( Vicia faba cv. Fiord) as a protein source for laying hens
African Journals Online (AJOL)
Dehulled faba beans were evaluated as an alternative to soybeans as a protein source for laying hens using 240 individually caged birds, 50 weeks of age. Two basal feeds were formulated to the same nutrient specifications but with one containing no faba beans and the other containing 200 g dehulled faba bean meal/kg.
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Provisional catalogue of the flora of San Ignacio de Huinay, Chile
Directory of Open Access Journals (Sweden)
Ramón Morales
2016-09-01
Full Text Available Contribution to the vascular plants flora of San Ignacio de Huinay natural reserve, Comau fiord, Región de los Lagos, Chile. To date, 262 species with their herbaria sheets stored in 5 different American and European herbaria (CONC, M, MA, and SGO and that of Huinay, are known in the territory. In this work some first new records for the South Cone are included, such as Potentilla anglica, Plantago media, and Mentha x rotundifolia. Furthermore, some of the records are new for the Flora of Chile, such as Juncus burkartii, only known from Argentina. Other species very scarcely cited in Chile, such as Solanum nigrum and Bromus squarrosus, are also included.
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Evaluation of dehulled faba bean (Vicia faba cv. Fiord) as a protein ...
African Journals Online (AJOL)
p2492989
food intake increased linearly with faba bean inclusion, reflecting a need by the hens ... Hens consumed the same amount of each basal feed when given a choice ... reduced transport cost could make this an attractive alternative to soybeans.
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Environmental Impacts of Shipping to and from Citronen Fjord
DEFF Research Database (Denmark)
Boertmann, D.
. The waters off Citronen Fjord are covered by ice throughout the year. Fast ice covers Frederick E. Hyde Fjord and the coastal waters off the outer coast, and pack ice covers the Wandel Sea and the majority of the Greenland Sea. Sailing in these waters will require powerful icebreaking capabilities...... Henrik Krøyer Holme are the most sensitive to sailing and icebreaking. Sailing and icebreaking in these areas should be avoided. The movement of icebreakers through the fast ice of Frederick E. Hyde Fjord may alter the habitat of a population of ringed seals that inhabit the fiord. Incidental oil spills...... from the ships sailing to and from Citronen Fjord poses the most serious threats to the wildlife in the area covered by this report....
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DEFF Research Database (Denmark)
Mouritsen, Kim N.; Hedeholm, Rasmus; Schack, Henriette B.
2010-01-01
Anisakid nematodes commonly infect gadids, and are of economic and aesthetic importance to the commercial fishing industry in Greenland as some species are pathogenic to humans. However, very little is known about the occurrence of these parasites and their impact on the hosts in Greenland waters....... During a survey in 2005, stomach sample of 227 Atlantic cod (Gadus morhua) and 64 Greenland cod (Gadus ogac) was collected in Godthaab and Sisimiut fiord systems in West Greenland waters. All cod were dissected for stomach contents and anisakid nematodes were removed from the visceral cavity. Third stage...... nematode species regarding prevalence of infection and mean infection intensity was evident, and there was no relationship between fish condition and the intensity of nematode infections. Standardised for size, capelin-eating cod were in better condition and more heavily infected than fish subsisting...
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Earthquakes in Fiordland, Southern Chile: Initiation and Development of a Magmatic Process
Barrientos, S.; Service, N. S.
2007-05-01
Several efforts in Chile are being conducted in relation to geophysical monitoring with the objective of disaster mitigation. A long and permanent monitoring effort along the country has been the continuous effort resulting in the recognition and delineation of new seismogenic sources. Here we report on the seismo-volcanic crisis that is currently taking place in the in the region close to the triple junction (Nazca, Antarctica and South America) in southern Chile at around latitude 45°S. On January 22, 2007, an intensity V-VI (MMI) earthquake shook the cities of Puerto Aysén, Puerto Chacabuco and Coyhaique. This magnitude 5 event, was the first of a series of earthquakes that have taken place in the region for nearly a month and a half (until end of February, time when this abstract was written). The closest station to the source area -part of the GEOSCOPE network located in Coyhaique, about 80 km away from the epicenters- reveals seismic activity about 3 hours before the first event. Immediately after the first event, more than 20 events per hour were detected and recorded by this station, rate which decreased with time with the exception of those time intervals following larger events. More than six events with magnitude 5 or more have been recorded. Five seismic stations were installed surrounding the epicentral area between 27 - 29 January and are currently operational. After processing some of the recorded events, a sixth station was installed at the closest possible site of the source of the seismic activity. Preliminary analysis of the recorded seismic activity reveals a concentration of hypocenters - 5 to 10 km depth- along an eight-km NNE-SSW vertical plane crossing the Aysén fiord. Harmonic tremor has also been detected. This seismic activity is interpreted as the result of a magmatic process in progress which will most likely culminate in the generation of a new underwater volcanic edifice. Because the seismic activity fully extends across the Ays
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2012-05-08
... Federal Information Relay Service (FIRS) at 1-800-877-8339 between 8 a.m. and 8 p.m., Eastern Time, Monday... transition to a sustainable wood product industry based on young-growth managment. The underlying need for... provide their comments at such times and in such manner that they are useful to the agency's preparation...
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International Nuclear Information System (INIS)
Quesada Alpizar, Marco A.; Cortes, Jorge
2006-01-01
A review of the existing scientific literature on marine ecosystems in the South Pacific of Costa Rica is presented. Most of the information generated to date concentrates on the Golfo Dulce area, a tropical fiord and only anoxic basin in the American pacific coast. Even thought there is a considerable amount of information available, there are still many aspects of the marine ecosystems of the region that remain unstudied. Among these, those concerning circulation patterns, mangrove dynamics, biodiversity of soft sediments and deep waters, and the ecology of commercially important species of mollusks, crustaceans and fish, stand out. Special attention should be placed on the study of Golfo Dulce, Isla del Cano and the Terraba-Sierpe mangrove system, give their biological importance and unique regional character. Coastal management in the region should be based on the best scientific information available integrating biological, social and economic criteria; and seeking the improvement of inter-institutional coordination in order to achieve integrative solutions to the existing threats to marine resources. (author) [es
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Directory of Open Access Journals (Sweden)
Stuart Innes
2002-07-01
Full Text Available Belugas (Delphinapterus leucas caught by hunters from various hamlets in the Arctic differed in the concentrations of organochlorine contaminants in their blubber. By applying Canonical Discriminant Analysis (CDA it was possible to separate all seven sampling locations from each other. Over 90% of the samples could be classified back to their landing location based on the data transformations developed by CDA. This analysis suggested that “stock” or management unit for belugas is best described by the culturally transmitted behaviour of their migration route. The analysis also provides evidence that most belugas caught by hunters from Grise Fiord are not the same as belugas caught while migrating along West Greenland; that some belugas caught in Sanikiluaq are not the same as beluga caught in the Nastapoka River estuary; and that the belugas caught in Kimmirut are not the same as belugas caught in Cumberland Sound. There is a need to redefine the stock descriptions of some belugas in Canada and Greenland.
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Ocean anoxia did not cause the Latest Permian Extinction
Proemse, Bernadette C.; Grasby, Stephen E.; Wieser, Michael E.; Mayer, Bernhard; Beauchamp, Benoit
2014-05-01
The Latest Permian Extinction (LPE, ~252 million years ago) was a turning point in the history of life on Earth with a loss of ~96% of all marine species and ~70% of all terrestrial species. While, the event undoubtedly shaped the evolution of life its cause remains enigmatic. A leading hypothesis is that the global oceans became depleted in oxygen (anoxia). In order to test this hypothesis we investigated a proxy for marine oxygen levels (molybdenum isotopic composition) in shale across the LPE horizon located on the subtropical northwest margin of Pangea at that time. We studied two sedimentary records in the Sverdrup basin, Canadian High Arctic: Buchanan Lake (eastern Axel Heiberg Island; 79° 26.1'N, 87° 12.6'W), representing a distal deep-water slope environment, and West Blind Fiord (southwest Ellesmere Island; 78° 23.9'N, 85° 57.2'W), representing a deep outer shelf environment (below storm wave base). The molybdenum isotopic composition (δ98/95Mo) of sediments has recently become a powerful tool as a paleo-oceanographic proxy of marine oxygen levels. Sample preparation was carried out in a metal-free clean room facility in the isotope laboratory of the Department of Physics and Astronomy, University of Calgary, Canada, that is supplied by HEPA-filtered air. Molybdenum isotope ratios were determined on a Thermo Scientific multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) with an uncertainty better than ±0.10o for δ98/95Mo values. Results from the Buchanan Lake section show a large shift in δ98/95Mo values from 2.02o to +2.23o at the extinction horizon, consistent with onset of euxinic conditions. In contrast, West Blind Fiord shales, representing the sub-storm wave base shelf environment, show little change in the molybdenum isotopic composition (1.34o to +0.05), indicating ongoing oxic conditions across the LPE (Proemse et al., 2013). Our results suggest that areas of the Pangea continental shelf (North West Pangea) experienced
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Energy Technology Data Exchange (ETDEWEB)
Larsen, Ib [Research Establishment Risoe, Danish Atomic Energy Commission (Denmark)
1960-07-01
Because of the low rate of water renewal in the recipient, Roskilde Fiord, an efficient decontamination plant incorporating an evaporator has been constructed at the Risoe research establishment. It is intended that the activity of the fiord-water at a distance of ten metres from the discharge point shall be less than one-tenth of the drinking-water tolerance. This will correspond to ca. 1 millicurie per month contained in ca. 5000 m{sup 3} of effluent. A description of the control and collection of laboratory effluents, of the decontamination plant and of the residue storage building will be given. The results of current experiments dealing with the decontamination factor and the economic aspects of the problem will also be given. (author) [French] Vu la lenteur du rythme de renouvellement des eaux dans le fjord de Roskilde, qui recoit les effluents du centre de recherche de Risoe, une installation efficace de decontamination, munie d'un evaporateur, a ete construite dans le centre. La radioactivite des eaux du fjord, a une distance de dix metres de l'orifice de vidange, devra rester inferieure au dixieme de la dose maximum admissible pour l'eau potable, ce qui correspond a une dose mensuelle approximative d'un millicurie pour environ 5.000 metres cubes d'effluents. Le memoire contient une description du controle et de la collecte des effluents du laboratoire, de l'installation de decontamination et du batiment servant a l'entreposage des residus. L'auteur expose en outre les resultats des experiences en cours sur le facteur de decontamination et sur les aspects economiques du probleme. (author) [Spanish] Debido al bajo indice de renovacion de las aguas en el fiordo de Roskildo, en el que se vierten los desechos radiactivos del Centro de Investigaciones de Risoe, se esta construyendo en el Centro una eficaz instalacion de descontaminacion de la que forma parte un evaporador. Se pretende con ello que la radiactividad de las aguas del fiordo, a una distancia de 10
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Pollutants in harp seals (Phoca groenlandica). I. Organochlorines
Energy Technology Data Exchange (ETDEWEB)
Ronald, K; Frank, R J; Dougan, J L; Frank, R; Braun, H E
1984-09-01
Between 1976 and 1978, 248 harp seals were sampled from 5 locations in the Northwest Atlantic and Arctic for organochlorine (OC) residue analysis in tissue. Blood, kidney, brain, muscle and blubber samples were analysed for PCB, DDT, dieldrin, hexachlorobenzene (HCB), and heptachlor epoxide. Levels were generally greatest in blubber tissue. Overall, mean levels of DDT and PCB were greater than those of other OC. A barrier prevented OC compounds from accumulating in the brain to the level one might expect in lipid tissues. Positive correlations were found between 1: DDT and PCB, 2: DDT and dieldrin, and 3: PCB and deildrin. Male harp seals bioaccumulated DDT, PCB, heptachlor epoxide and dieldrin with age. As a group, adult males sampled in the Gulf of St. Lawrence carried the highest concentrations of all OC, except that chlordane did not appear to bioaccumulate and levels of hexachlorobenzene were minimal. Females generally ceased exhibiting significant bioaccumulation once breeding age was reached, due to transplacental and transmammary residue transfer of OC from mother to pup. There were some significant differences in OC levels between locations with DDT: Gulf greater than Front; PCB: Gulf greater than Front; dieldrin: Gulf greater than Front; heptachlor epoxide: Front greater than Gulf. No significant differences were found, however, when northern locations (Grise Fiord, Northwest Greenland, Pangnirtung) were compared to southern (Gulf, Front) on a group basis.
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Age of the last glaciation of Vestfold Hills and significance for sea level change
International Nuclear Information System (INIS)
Gore, D.B.; Colhoun, E.A.
1998-01-01
The Vestfold Hills form the second largest deglaciated oasis area in East Antarctica. The last time that the oasis was submerged by the East Antarctic ice sheet as it extended onto the continental shelf has been termed the ''Vestfold Glaciation'' (Adamson and Pickard 1986). To date the Vestfold Glaciation has been assumed to correlate with the late Wisconsin Glaciation on the basis of Holocene radiocarbon dates obtained from marine deposits in the inlets and from derived sediments ice-proximal to the margin of the Sorsdal Glacier (Adamson and Pickard 1986; Fitsimons and Dormack 1993). Radiocarbon dating of shell fragments from Vestfold till deposits distributed throughout the southern and seaward parts of the oasis have given assays from 31.1 to .43.7k yr BP. If the assays represent true ages of the time of growth of the marine shells then it would appear that the Vestfold Glaciation ice expansion onto the continental shelf post-dates 31 k yr and the glaciation is equivalent to the late Wisconsin. Similarly, if the range of assays represents true ages then the fiords must have been occupied by the sea during late middle Wisconsin time, presumably when the continental margin was isostatically depressed below present level. There is, however, the possibility that the assays are minimal, and being derived into till from older marine deposits they could have true greater and mixed ages. This alternative is being explored
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Nordic exchange of students and climate change.
Thomsson, A.
2012-04-01
Since the end of 2010 and until the summer of 2011 two upper secondary schools in Höyanger, Norway and Ronneby, Sweden had the possibility to take part in a project called Nordplus junior. The main aims of the program are: • To promote Nordic languages and culture and mutual Nordic-Baltic linguistic and cultural understanding. • To contribute to the development of quality and innovation in the educational systems for life-long learning in the participating countries by means of educational cooperation, development projects, exchanges and networking. • To support, develop, draw benefit from and spread innovative products and processes in education through systematic exchange of experiences and best practice. • To strengthen and develop Nordic educational cooperation and contribute to the establishment of a Nordic-Baltic educational area. The students did research on climate change and the impact on local and regional areas. Many questions had to be answered, giving an explanation to what happens if the climate changes. Questions related to Höyanger, Norway What happens to life in Norwegian fiords? Which attitudes do youngsters and adults have about climate change and what actions do they take? What does a rise in sea level mean for Höyanger? How are different tourist attractions affected in western Norway? Questions related to Ronneby, Sweden How is the regional fauna and flora affected? What will happen to agriculture and forestry? What do adults and youngsters know about consequences of a possible climate change? What happens to the people of Ronneby if the sea level rises? Are there any positive outcomes if the climate changes? Conclusions In Norwegian fiords there could be benefits because fish are growing faster in the winter because of an increased temperature. At the same time there could be an imbalance in the ecosystem because of a change in the living ranges of different species. Most of the young boys and girls in Höyanger, Norway were
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DEFF Research Database (Denmark)
Sloth, Jens Jørgen; Julshamn, Kåre
2008-01-01
arsenic. Total arsenic was determined using inductively coupled plasma mass spectrometry (ICPMS) following microwave-assisted acidic digestion of the samples. Inorganic arsenic was determined using an anion-exchange HPLC-ICPMS method following microwave-assisted alkaline solubilization of the samples...
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DEFF Research Database (Denmark)
Vandieken, V.; Knoblauch, C.; Jørgensen, BB
2006-01-01
(.)0-95(.)7% 16S rRNA gene sequence similarity), Strains 18(T) and 77, exhibiting 99(.)9% sequence similarity, represent a novel species for which the name Desulfovibrio frigidus sp. nov. is proposed. The type strain is strain 18(T) (=DSM 17176(T)=jCM 12924(T)). Strain 61(T) was closely related to strains 18(T...
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Molnia, B. F.; Karpilo, R. D.; Pranger, H. S.
2004-12-01
Historical photographs, many dating from the late-19th century are being used to document landscape and glacier change in the Glacier Bay area. More than 350 pre-1980 photographs that show the Glacier Bay landscape and glacier termini positions have been acquired by the authors. Beginning in 2003, approximately 150 of the sites from which historical photographs had been made were revisited. At each site, elevation and latitude and longitude were recorded using WAAS-enabled GPS. Compass bearings to photographic targets were also determined. Finally, using the historical photographs as a composition guide, new photographs were exposed using digital imaging and film cameras. In the laboratory, 21st century images and photographs were compared with corresponding historical photographs to determine, and to better understand rates, timing, and mechanics of Glacier Bay landscape evolution, as well as to clarify the response of specific glaciers to changing climate and environment. The comparisons clearly document rapid vegetative succession throughout the bay; continued retreat of larger glaciers in the East Arm of the bay; a complex pattern of readvance and retreat of the larger glaciers in the West Arm of the bay, coupled with short-term fluctuations of its smaller glaciers; transitions from tidewater termini to stagnant, debris-covered termini; fiord sedimentation and erosion; development of outwash and talus features; and many other dramatic changes. As might be expected, 100-year-plus photo comparisons show significant changes throughout the Glacier Bay landscape, especially at the southern ends of East and West Arms. Surprisingly, recent changes, occurring since the late-1970s were equally dramatic, especially documenting the rapid thinning and retreat of glaciers in upper Muir Inlet.
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Extrapolation of tectonic boundaries across the Labrador shelf: U-Pb geochronology of well samples
International Nuclear Information System (INIS)
Wasteneys, H.A.; Krogh, T.E.
1996-01-01
Near Saglek Fiord, a northerly trending boundary between the early Archean Saglek block and the middle Archean Hopedale block extends between drill sites which, respectively, sampled Uivak amphibolite gneiss with U-Pb zircon intercept ages of 3742 ± 12 and 2752 ± 42 Ma, and migmatitic Lister gneiss with concordant ages of 3213 -4 +21 Ma for restite and 2552 -21 +4 Ma for leucosome. Titanite ages of ca. 2508 Ma are common to both rocks. A nearby metapsammitic gneiss has detrital zircon and monazite ages of 2681 ± 5, 2700 ± 4, ca. 2730, and 2750 ± 2 Ma representing high-grade metamorphism related to the Hopedale-Saglek collision and metamorphic monazite of ca. 2560 Ma age representing metamorphism of the sediment during reactivation of the Saglek-Hopedale suture. Two hundred kilometres southeast, a gneissic granite records a protolith age of 3170 Ma and Late Proterozoic Pb loss. Near the Nain-Makkovik boundary, 1269 ± 4 Ma zircons indicate a significant extension of the Nain Plutonic Suite. South of the Makkovik boundary, a foliated granite yielded an upper intercept age defining intrusion at 1895 ± 8 Ma and concordant 1872 ± 5 Ma titanite ages that date subsequent metamorphism. Discordant U-Pb ages from an alkali-feldspar granite also constrain crystallization to ca. 1890 Ma and together with the gneiss represent the previously defined Iggiuk event in the Kaipokok domain. Wells near the southerly end of the transect record 1801 ± 5, 1813 ± 3, and 1806 ± 8 Ma ages, respectively, that are typical of the synorogenic granitoid suite representing the Cape Harrison domain of southern Makkovik Province. (author). 46 refs., 1 tab., 5 figs
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Low temperature S(0) biomineralization at a supraglacial spring system in the Canadian High Arctic.
Gleeson, D F; Williamson, C; Grasby, S E; Pappalardo, R T; Spear, J R; Templeton, A S
2011-07-01
Elemental sulfur (S(0) ) is deposited each summer onto surface ice at Borup Fiord pass on Ellesmere Island, Canada, when high concentrations of aqueous H(2) S are discharged from a supraglacial spring system. 16S rRNA gene clone libraries generated from sulfur deposits were dominated by β-Proteobacteria, particularly Ralstonia sp. Sulfur-cycling micro-organisms such as Thiomicrospira sp., and ε-Proteobacteria such as Sulfuricurvales and Sulfurovumales spp. were also abundant. Concurrent cultivation experiments isolated psychrophilic, sulfide-oxidizing consortia, which produce S(0) in opposing gradients of Na(2) S and oxygen. 16S rRNA gene analyses of sulfur precipitated in gradient tubes show stable sulfur-biomineralizing consortia dominated by Marinobacter sp. in association with Shewanella, Loktanella, Rubrobacter, Flavobacterium, and Sphingomonas spp. Organisms closely related to cultivars appear in environmental 16S rRNA clone libraries; none currently known to oxidize sulfide. Once consortia were simplified to Marinobacter and Flavobacteria spp. through dilution-to-extinction and agar removal, sulfur biomineralization continued. Shewanella, Loktanella, Sphingomonas, and Devosia spp. were also isolated on heterotrophic media, but none produced S(0) alone when reintroduced to Na(2) S gradient tubes. Tubes inoculated with a Marinobacter and Shewanella spp. co-culture did show sulfur biomineralization, suggesting that Marinobacter may be the key sulfide oxidizer in laboratory experiments. Light, florescence and scanning electron microscopy of mineral aggregates produced in Marinobacter experiments revealed abundant cells, with filaments and sheaths variably mineralized with extracellular submicron sulfur grains; similar biomineralization was not observed in abiotic controls. Detailed characterization of mineral products associated with low temperature microbial sulfur-cycling may provide biosignatures relevant to future exploration of Europa and Mars. © 2011
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Lehmann, Sara; Kociuba, Waldemar; Franczak, Łukasz; Gajek, Grzegorz; Łeczyński, Leszek; Kozak, Katarzyna; Szopińska, Małgorzata; Ruman, Marek; Polkowska, Żaneta
2014-10-01
The study area covered the NW part of the Wedel Jarlsberg Land (SW part of the Svalbard Archipelago). The primary study object was the catchment of the Scott Glacier in the vicinity of the Research Station of of Maria Curie-Skłodowska University in Lublin - Calypsobyen. The Scott River catchment (of glacial hydrological regime) has an area of approximately 10 km2, 40% of which is occupied by the valley Scott Glacier in the phase of strong recession. The present study concerns the determination of physical and chemical parameters (pH, conductivity, TOC) and concentrations of pollutants (phenols, aldehydes).
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Chemical speciation and adsorption behavior of plutonium in natural waters
International Nuclear Information System (INIS)
Sanchez, A.L.
1983-01-01
Dissolved Pu profiles in two partially anoxic basins--Saanich Inlet, an intermittently anoxic marine fiord in Vancouver Island, British Columbia, and Soap Lake, a saline, alkaline lake in eastern Washington state, revealed minimum concentrations at the O 2 /H 2 S interface. The Pu concentrations in the anoxic waters of Saanich Inlet were less than the surface concentrations; however, in Soap Lake, a 15- to 50-fold increase in Pu concentration in the anoxic monimolimnion correlated with large increases in the major ions, total alkalinity, and dissolved organic carbon. Laboratory experiments were designed to investigate the effects of pH, ionic strength, dissolved organic carbon, and carbonate ions on the adsorption of tracer amounts of Pu IV and Pu V. The Pu-goethite adsorption system provided the data base for developing a thermodynamic model of Pu interaction with an oxide surface and with dissolved ligands, using the MINEQL computer program. Pu IV and Pu V interacted very differently with goethite, which is consistent with their different hydrolytic character. A reduction of Pu V to Pu IV occurred on the goethite surface and also on montmorillonite and silica gel, suggesting that redox transformations are an important aspect of Pu adsorption. Increases in ionic strength (up to 3 M NaCl or NaNO 3 ) did not affect Pu IV or V adsorption. In the presence of dissolved organic carbon (DOC), Pu V reduction to Pu IV occurred in solution. Pu IV adsorption on goethite decreased only 30% in the presence of 240 ppm of natural DOC from Soap Lake; however, carbonate anions inhibited Pu IV adsorption on goethite at the alkalinity levels (1500 meq/L total alkalinity, 0.57 M CO 3 =) measured for Soap Lake monimolimnion waters
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Organic carbon in glacial fjords of Chilean Patagonia
Pantoja, Silvio; Gutiérrez, Marcelo; Tapia, Fabián; Abarzúa, Leslie; Daneri, Giovanni; Reid, Brian; Díez, Beatriz
2016-04-01
The Southern Ice Field in Chilean Patagonia is the largest (13,000 km2) temperate ice mass in the Southern hemisphere, yearly transporting ca. 40 km3 of freshwater to fjords. This volume of fresh and cold water likely affects adjacent marine ecosystems by changing circulation, productivity, food web dynamics, and the abundance and distribution of planktonic and benthic organisms. We hypothesize that freshwater-driven availability of inorganic nutrient and transport of organic and inorganic suspended matter, as well as microbes, become a controlling factor for productivity in the fjord associated with the Baker river and Jorge Montt glacier. Both appear to be sources of silicic acid, but not of nitrate and particulate organic carbon, especially during summer, when surface PAR and glacier thawing are maximal. In contrast to Baker River, the Jorge Montt glacier is also a source of dissolved organic carbon towards a proglacial fjord and the Baker Channel, indicating that a thorough chemical description of sources (tidewater glacier and glacial river) is needed. Nitrate in fiord waters reaches ca. 15 μM at 25 m depth with no evidence of mixing up during summer. Stable isotope composition of particulate organic nitrogen reaches values as low as 3 per mil in low-salinity waters near both glacier and river. Nitrogen fixation could be depleting δ15N in organic matter, as suggested by the detection at surface waters of nif H genes belonging to diazotrophs near the Montt glacier. As diazotrophs have also been detected in other cold marine waters (e.g. Baltic Sea, Arctic Ocean) as well as glaciers and polar terrestrial waters, there is certainly a potential for both marine and freshwater microbes to contribute and have a significant impact on the Patagonian N and C budgets. Assessing the impact of freshwater on C and N fluxes and the microbial community structure in Patagonian waters will allow understanding future scenarios of rapid glacier melting. This research was funded
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Stramska, Malgorzata; Yngve Børsheim, Knut; Białogrodzka, Jagoda; Cieszyńska, Agata; Ficek, Dariusz; Wereszka, Marzena
2016-04-01
There is still a limited knowledge about suspended and dissolved matter fluxes transported from coastal regions into the open sea regions in the Arctic. The land/sea interface is environmentally important and sensitive to climate change. Important biogeochemical material entering the oceans (including carbon) passes through this interface, but too little is known about the efficiency of this transport. Our goal in the NORDFLUX program is to improve quantitative understanding of the environmental feedbacks involved in these processes through an interdisciplinary study with innovative in situ observations. Completed work includes two in situ experiments in the Norwegian fiord (Porsangerfjorden) in the summers of 2014 and 2015. Experiments used research boat for collection of water samples and in situ bio-optical data, an autonomous glider, mooring with T S sensors, and a high frequency radar system. We have used these data to derive spatial maps of water temperature, salinity, surface currents, chlorophyll fluorescence, dissolved organic matter (DOM) fluorescence, and inherent optical properties (IOPs) of the water. The interpretation of these data in terms of suspended matter concentration and composition is possible by in situ 'calibrations' using water samples from discrete hydrographic stations. Total suspended matter (TSM), particulate carbon (POC and PIC), and dissolved organic carbon (DOC) concentrations together with measured water currents will allow us to estimate reservoirs and fluxes. Concentrations and fluxes will be related to physical conditions and meteorological data. An important aspect of this project is the work on regional ocean color algorithms. Global ocean color (OC) algorithms currently used by NASA do not perform sufficiently well in coastal Case 2 waters. Our data sets will allow us to derive such local algorithms. We will then use these algorithms for interpretation of OC data in terms of TSM concentrations and composition and DOC. After
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Herrle, Jens O.; Schröder-Adams, Claudia J.; Galloway, Jennifer M.; Pugh, Adam T.
2013-04-01
Understanding the evolution of Canada's Arctic region, as a crucial component of Earth's climate system, is fundamental to assess short and long-term climate, environmental, and paleogeographic change. However, the stratigraphy and paleoenvironmental evolution of the Cretaceous Arctic is poorly constrained and a detailed bio- and chemostratigraphic correlation of major mid-Cretaceous paleoceanographic turning points such as Oceanic Anoxic Events, cold snaps, and biotic turnovers with key locations of the high- and low latitudes is missing. Here we present for the first time a high resolution bio- and carbon isotope stratigraphy of the Arctic Albian Christopher Formation of the Sverdrup Basin at Glacier Fiord in the southern part of Axel Heiberg Island, Canadian High Arctic. By using these techniques we developed a high temporal framework to record major environmental changes as it is indicated by the occurrence of glendonites and sandstone intervals of our studied Albian succession. The Albian Christopher Formation is a shale dominated marine unit with a thickness of approximately 1200 m. Several transgressive/ regressive cycles can be recognized by prograding shoreface units that break up mudrock deposition. In addition, glendonites are mainly found in the lower part of the Christopher Formation. Glendonites are pseudomorphs of calcite, after the metastable mineral ikaite, and have been often described from high latitude Permian, Jurassic and Cretaceous marine environments from the Canadian Arctic, Spitsbergen and Australia. The formation of glendonites takes place in the uppermost layer of the sediment and requires near-freezing temperatures, high salinity, and orthophosphate-rich bottom water. Although the presence of glendonites implies a range of paleoenvironmental conditions there is a consensus in the scientific literature that they reflect cooler paleoenvironmental conditions. Preliminary bio- and carbon isotope stratigraphic results suggest that the
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The teachers at Sea program of the Committee on Education of EGU
Laj, Carlo; Kissel, Catherine; Leau, Hélène
2015-04-01
"Teachers at sea" is an Educational Program making it possible for high school teachers to participate to oceanographic cruises together with the scientists. With the support of the French Polar Insitute (IPEV) and of EGU, 3 editions of this program have taken place on board the R/V Marion Dufresne during cruises PACHIDERME in 2007 (along the Coast and in the fiords of Southern Chile), AMOCINT in 2008 (in the North Atlantic Ocean), and CIRCEA (in the South China Sea in 2012) Another edition took place in 2014, aboard the oceanographic cruise PREPARED (PREsent and PAst flow REgime on contourite Drifts west of Spitsbergen, onboard the Norwegian Research Vessel G.O Sars from 05 to 15 June 2014. The expedition was part of the EUROFLEETS On board, the teachers participated to all the scientific activities. In order to be fully immersed in the scientific work, the teachers also participated together with the scientists and technicians to two 4-hours shifts per day (8h total per day). During these shifts, they were involved in every step of the process of obtaining the cores, cutting, opening and labelling them, archiving, and measuring some of the physical parameters, and finally sediment description. It was possible to establish almost daily reports of the scientific progress of the cruise and to send regular logs to the participating land-based teachers in different schools mainly in Europe and in the USA, taking advantage of a list of addresses of teachers having participated to the Geosciences Information for teachers (GIFT) workshops of the European Geosciences Union. This should bring authentic science in the classroom, and indeed we received enthusiastic responses from many teachers. Exposure to authentic science, such as that the teachers have experienced during these oceanographic cruises, may be a pivotal experience for them, causing them to change at least in part their teaching methods, possibly creating more future scientists or at least adults with positive
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Directory of Open Access Journals (Sweden)
CLAUDIO VALDOVINOS
2005-09-01
Full Text Available Taxonomically, the Mollusca of the southern end of South America are moderately well known, but the literature is scattered, there is little information on their habitats, and distributional records are scarce for the Chilean archipelago lying between Chiloé Island (42° S and Tierra del Fuego (55° S. Although much is known about the biology and ecology of of some species of Nacellidae, the taxonomy of the group have been partially neglected, particularly in remote areas of the world such as the Chilean fjords. Therefore, this study aims to clarify the nomenclatural status, and establish the morphological characteristics and distribution of the Chilean Nacellidae. Especially, the following three objectives are pursued: (i to clarify the correct identity of existing species; (ii to describe of morphological details, highlighting the clear diagnostic characters of each species, and (iii to delimitate and discuss their geographical range in Chile. The examination of the Nacellidae of the Chilean fiords has resulted in the recognition of one species of Nacella (Nacella and seven species of Nacella (Patinigera, wherein the principal specific differences are in the shell (shape, thickness and color and in radular teeth morphology. The genus Nacella and its subgenus Patinigera are cold-water limpets, and are exclusively inhabitants of Subantarctic and Antarctic waters. The greater part of their range being subantarctic, but extending to the Antarctic by way of the Scotia Arc, and also ranging northward up the Chilean coast to at least Valparaiso at 33° S (only N. (P. clypeater. They apparently have their centre of distribution in the Magellanic Province of southern South America, corresponding to an area with a high degree of diversification (N. (N. mytilina, N. (P. chiloensis, N. (P. deaurata, N. (P. delicatissima, N. (P. flammea, N. (P. magellanica, N. (P. venosa, wherefrom the species tends to spread eastward, with a larval transport probably
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Directory of Open Access Journals (Sweden)
Daniela Sauer
2013-07-01
ón de arcilla se refleja en un aumento del espesor de los revestimientos de arcilla y de la proporción de poros con revestimientos de arcilla. La movilización de arcilla y la co-eluviación de hierro en las partes más superficiales de los horizontes Eg cesa en suelos con menos de 2,1 ka, mientras que la meteorización y formación de minerales de la arcilla y óxidos de hierro continúa, dando lugar a la formación de un horizonte BE en la parte más superficial del horizonte Eg. Las lenguas albelúvicas aparecen tras 4,6-6,2 ka y se desarrollan preferentemente a lo largo de las grietas de desecación. El material albelúvico se lava hacia las grietas y en ellas se produce un aumento de lavado de bases y la eluviación de la arcilla. A medida que ambos procesos progresan, las lenguas albelúvicas se hacen más largas y anchas. Las intercalaciones arcillosas se producen en el Albeluvisol Estágnico de la secuencia. La génesis propuesta es la siguiente: cuando tras el deshielo o algún periodo húmedo, el agua que se va infiltrando alcanza la parte inferior de una lengua albelúvica, la lengua se llena de agua y el agua colgada se acumula también sobre la parte superior del horizonte Btg denso. El agua, cargada de arcilla en suspensión, penetra bajo presión desde la lengua en el horizonte Btg, donde se produce una movilización adicional de arcilla. La arcilla se va acumulando cuando la velocidad del agua disminuye, formando intercalaciones arcillosas en la matriz densa del horizonte Btg.Este trabalho descreve observações micromorfológicas relativas às duas únicas cronosequências de Albeluvisols até agora referidas na literatura internacional. Estas observações foram combinadas com os dados existentes sobre o perfil micromorfológico e caraterísticas químicas do solo de forma a identificar os principais processos envolvidos na formação dos Albeluvisols. A área de estudo situa-se nos condados Vestfold e Østfold no lado ocidental e oriental do Fiorde