Absolute dating of the youngest sediments of the Swiss Molasse basin by apatite fission track analysis     

Meinert K. Rahn  Rune Selbekk 《Swiss Journal of Geoscience》2007,100(3):371-381

A set of ash layer samples within the uppermost Upper Freshwater Molasse (OSM) sediments (N and E of Frauenfeld, Switzerland) was dated by apatite fission track (FT) means. The ages indicate an early Tortonian (perhaps latest Serravallian) eruption and sedimentation age of 11.5 ± 0.3 Ma. The age is in agreement with time constraints by Mammalian relicts which point to MN7-8. Due to the position of the ash layers close to the erosional gap and overlying Quaternary cover, the age represents a maximum age for the cessation of OSM sedimentation in the Swiss Molasse Basin. However, the end of Molasse sedimentation in this region had not stopped before the cover of OSM sediments by volcanic ash layers at the Höwenegg volcano (southern Germany), an event further constrained by an apatite FT age of 9.8 (?0.7/+0.8) Ma from a hornblende-bearing ash layer at Höwenegg. An isolated bentonitic ash layer occurring 25 km to the WSW of the main set of dated ashes (near Humlikon) has an age component identical to the OSM ash layers near Frauenfeld. The age suggests a source for this material within the Hegau, but is too young to be related to the volcanic activity at the Kaiserstuhl.The apatites from the ash layer samples show two distinct compositional populations, one very close to a Cl end member and one with apatites of equal proportions of Cl and OH end member. These populations are interpreted to have possibly originated from at least two distinct igneous sources for the ashes, separated by their eruption site or eruption time or both. The distinct compositional data on the volcanic apatites may provide a basis to clarify their origin in future work.  相似文献   

Behaviour of mackerel schools during summer feeding migration in the Norwegian Sea, as observed from fishing vessel sonars   总被引：1，自引：0，他引：1  

Godo  Olav Rune; Hjellvik  Vidar; Iversen  Svein A.; Slotte  Aril; Tenningen  Eirik; Torkelsen  Terje 《ICES Journal of Marine Science》2004,61(7):1093-1099

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Report on Kukk?m?ki's method for computing the levelling effect of atmospheric refraction     

G. A. Rune 《Journal of Geodesy》1950,24(4):432-433

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Low-frequency variability of surface air temperature over the Barents Sea: causes and mechanisms     

Eveline C. van der Linden  Richard Bintanja  Wilco Hazeleger  Rune G. Graversen 《Climate Dynamics》2016,47(3-4):1247-1262

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Large slope deformations detection and monitoring along shores of the Potrerillos dam reservoir,Argentina, based on a small-baseline InSAR approach   总被引：1，自引：0，他引：1  

Clément Michoud  Valérie Baumann  Tom Rune Lauknes  Ivanna Penna  Marc-Henri Derron  Michel Jaboyedoff 《Landslides》2016,13(3):451-465

The Argentina National Road 7 that crosses the Andes Cordillera within the Mendoza province to connect Santiago de Chile and Buenos Aires is particularly affected by natural hazards requiring risk management. Integrated in a research plan that intends to produce landslide susceptibility maps, we aimed in this study to detect large slope movements by applying a satellite radar interferometric analysis using Envisat data, acquired between 2005 and 2010. We were finally able to identify two large slope deformations in sandstone and clay deposits along gentle shores of the Potrerillos dam reservoir, with cumulated displacements higher than 25 mm in 5 years and towards the reservoir. There is also a body of evidences that these large slope deformations are actually influenced by the seasonal reservoir level variations. This study shows that very detailed information, such as surface displacements and above all water level variation, can be extracted from spaceborne remote sensing techniques; nevertheless, the limitations of InSAR for the present dataset are discussed here. Such analysis can then lead to further field investigations to understand more precisely the destabilising processes acting on these slope deformations.  相似文献   

The use of (14)C tracer technique to assess the functional response of zooplankton community grazing to toxic impact     

Hjorth M  Haller R  Dahllöf I 《Marine environmental research》2006,61(3):339-351

The use of functional endpoints in risk assessment of pollutants for marine pelagic communities is scarce, especially for the function of zooplankton communities. This work presents a rapid, inexpensive and ecologically relevant technique to assess the effect of toxic compounds on the grazing rates of zooplankton communities. The combination of a (14)C-tracer labelling technique with a fast (< 3 h) and representative sub-sampling and handling makes it possible to measure changes in food uptake of freshly collected natural zooplankton communities in a short-term assay. The methodology is described and its validity is determined by a full account of the fate of isotope tracers (up to 15% taken up by zooplankton). Egg production of Acartia tonsa cultures exposed to DCOI yielded EC(50) values of 118+/-33 nM DCOI after three days, where EC(50) values from grazing of natural zooplankton communities was 136+/-29 nM DCOI, indicating that grazing was the more sensitive variable. Finally the method was tested in a mesocosm experiment designed to evaluate the toxicity of the antifouling compound zinc pyrithion (ZPT) with an EC(50) value of 17 nM ZPT (SD=3.3 nM, n=3). The method was found to be reproducible both at the community (CV=8-39%) and individual level (CV=23-53%), and could detect small changes in response to a toxicant in a natural pelagic system. The use of natural communities in combination with the fast and cost-effective procedure makes this technique a powerful tool in risk assessment, where lack of ecological relevance or reproducible results often results in unwanted high uncertainties.  相似文献   

High voltage transmission lines and their effect on reindeer: a research programme in progress     

Eigil Reimers  Kjetil Flydal  Rune Stenseth 《Polar research》2000,19(1):75-82

We review literature on high voltage transmission lines and their effect on wild reindeer ( Rangifer tarandus ) migration patterns and area use. We conclude that reliable knowledge is lacking on the effects of transmission lines on reindeer ecology. This condition relates to the lack of long-term monitoring of reindeer migration patterns in relation to existing lines. It is also related to the fact that nothing is known about hearing in reindeer (or any other deer species in Norway) in relation to transmission line noise, which is considered an obstacle for migrating reindeer.
We then outline a research programme that includes a laboratory study to determine the audiogram in reindeer and two field studies to examine the proximate effects of transmission lines - independently as well as combined with ambient environmental variables - on reindeer behaviour. The audiogram in two yearling male reindeer has been determined; this part of the study will be completed this year with the determination of a corresponding audiogram in two female yearlings. The behaviour study of domestic reindeer under high voltage transmission lines was completed in September 1999. The behaviour study of wild reindeer in the area crossed by a 420 kV power line will continue this year and its completion is anticipated in 2001.  相似文献   

Comparison of Parameter Estimation Design Criteria Using a Solute Transport Model with Matrix Diffusion     

Rune Nordqvist 《Ground water》2000,38(6):827-835

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Comparison of geomorphological field mapping and 2D‐InSAR mapping of periglacial landscape activity at Nordnesfjellet,northern Norway          下载免费PDF全文

Markus Eckerstorfer  Harald Øverli Eriksen  Line Rouyet  Hanne H. Christiansen  Tom Rune Lauknes  Lars Harald Blikra 《地球表面变化过程与地形》2018,43(10):2147-2156

The ability to continuously monitor the dynamic response of periglacial landforms in a climate change context is of increasing scientific interest. Satellite radar interferometry provides information on surface displacement that can be related to periglacial processes. Here we present a comparison of two‐dimensional (2D) surface displacement rates and geomorphological mapping at periglacial landform and sediment scale from the mountain Nordnesfjellet in northern Norway. Hence, 2D Interferometric Synthetic Aperture Radar (InSAR) results stem from a 2009–2014 TerraSAR‐X dataset from ascending and descending orbits, decomposed into horizontal displacement vectors along an east–west plane, vertical displacement vectors and combined displacement velocity. Geomorphological mapping was carried out on aerial imagery and validated in the field. This detailed landform and sediment type mapping revealed an altitudinal distribution dominated by, weathered bedrock blockfields, surrounded primarily by slightly, to non‐vegetated solifluction landforms at the mountain tops. Below, an active rockslide and associated rockfall deposits are located on the steep east‐facing side of the study area, whereas glacial sediments dominate on the gentler western side. We show that 2D InSAR correctly depicts displacement rates that can be associated with typical deformation patterns for flat‐lying or inclined landforms, within and below the regional permafrost limit, for both wet and dry areas. A net lowering of the entire landscape caused by general denudation of the periglacial landforms and sediments is here quantified for the first time using radar remote sensing. Copyright © 2018 John Wiley & Sons, Ltd.  相似文献   

Innovation networks and green restructuring: Which path development can EU Framework Programmes stimulate in Norway?     

Giuseppe Calignano  Rune Dahl Fitjar  Nina Hjertvikrem 《Norsk geografisk tidsskrift. Norwegian journal of geography》2019,73(1):65-78

ABSTRACT

With combined insights from evolutionary economic geography and transition studies, the article examines the engagement of different regions in Norway in the innovation networks created within the European Union’s environmental programmes. The aim is to explore the programmes’ potential for supporting green economy and economic restructuring through branching and new path creation. The authors assess which regions participate in the programmes, which international networks they build, and which organisations participate in different regions. They compare three regions with different restructuring needs and research capacity – the counties of Rogaland, Hordaland, and Sør-Trøndelag (now part of the county of Trøndelag). They find that overall, Norwegian organisations participate relatively frequently in the programmes, but private firms play a marginal role. Their partners are mainly in core EU regions. Regional participation in the programmes is a function of research capacity as well as oil dependence. The authors conclude that in research-oriented regions, research establishments tend to dominate participation, creating potential for restructuring mainly through path creation. In oil-dependent regions, private firms account for a higher share of participants, enhancing the potential for branching. As the former regions participate more, the programme can mainly stimulate path creation.  相似文献