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   

Local habitat drivers of macrobenthos in the northern,central and southern KwaZulu-Natal Bight,South Africa     

CF MacKay  CB Untiedt  L Hein 《African Journal of Marine Science》2016,38(1):S105-S121

The relatively wide KwaZulu-Natal Bight between St Lucia and Durban on the north-east shelf of South Africa is characterised by several circulation features driven by the Agulhas Current, wind and coastal inputs. A large multidisciplinary programme investigated the sources and relative influences of nutrients on the shelf. Within this, and to address a critical knowledge gap, this study describes macrobenthic (<1 mm) composition and frequency from 16 stations, assigned amongst four oceanographic focus areas. The areas were predetermined across the disciplines to represent upwelling, outwelling and a semi-persistent eddy, with nutrients and primary productivity being measured at each. Environmental variables such as sediment distribution, sediment TOC and bottom water physico-chemistry were determined at a significantly larger spatial scale. Our study postulated that oceanographic focus areas support significantly different macrobenthic assemblages, and that composition and relative distribution is due to measurable habitat attributes at each. Macrofauna were relatively abundant and particularly rich at >1 000 taxa. Annelida, Arthropoda, Mollusca, Echinodermata, Sipuncula and Cnidaria (>50 taxa each) were the dominant macrobenthic groups in the bight. Annelida were dominated by the polychaete families Spionidae, Terrebelidae and Cirratullidae, which were generally associated with outwelling and a mud depocentre off the Thukela River. Two unique and distinctive assemblages were found, one in the Thukela Mouth focus area and another on the midshelf between Thukela and Durban. The latter is influenced by poorly sorted, coarse sand and with probable influences from the Durban Eddy. There assemblages were abundant, rich and specific to this habitat. Correlation, PERMANOVA and CAP analyses showed assemblage fidelity to the focus areas. Medium sand, fine sand, mud and the variance of overall sediment type were the habitat drivers underlying macrofaunal abundance distributions.  相似文献   

Projected changes in tropical cyclones over Vietnam and the South China Sea using a 25 km regional climate model perturbed physics ensemble     

Grace Redmond  Kevin I. Hodges  Carol Mcsweeney  Richard Jones  David Hein 《Climate Dynamics》2015,45(7-8):1983-2000

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Formation of corundum megacrysts during H<Subscript>2</Subscript>O-saturated incongruent melting of feldspar: P–T pseudosection-based modelling from the Skattøra migmatite complex,North Norwegian Caledonides     

Kåre Kullerud  Pritam Nasipuri  Erling J. K. Ravna  Rune S. Selbekk 《Contributions to Mineralogy and Petrology》2012,164(4):627-641

Corundum megacryst-bearing rocks associated with the high-pressure migmatites of the Skattøra migmatite complex (SMC) belonging to the Nakkedal Nappe Complex, North Norwegian Caledonides, display a classical example of incongruent melting of plagioclase under water-saturated conditions. Petrography and micro-textures suggest that several centimetre long corundum megacrysts formed from the silicate melt along with amphibole (pargasite) and plagioclase (X_An ~ 0.47). The corundum-bearing leucosomes are rich in biotite compared to the other mafic units of SMC. Locally, margarite occurs in coronas around corundum megacrysts. Geochemically, the corundum-bearing rocks are enriched in Al, K, Rb and Ba and depleted in Fe, Mg and Ca compared to the leucogabbroic host rock. A P–T pseudosection of the leucogabbro indicates that feldspar breakdown and corundum formation occurred at temperatures >850 °C and pressure >1.2 GPa. The calculated equilibrium P–T of the corundum-bearing rock corresponds to 750–825 °C and 0.9–1.1 GPa. The P–T pseudosection of margarite indicates that margarite formed after cooling and decompression to P–T conditions corresponding to 600 °C at 0.5 GPa. Based on geochemical and mineral chemical analysis coupled with thermodynamic modelling, we suggest that formation of corundum occurred as a result of high-pressure incongruent melting of plagioclase in the presence of a K-, Rb- and Ba-rich external fluid. It is also suggested that the external fluid transported out portions of Ca, Fe and Mg, resulting in an increase of the peraluminousity of the melt and promoting further growth of corundum.  相似文献   

Single-well and large-scale cross-hole tracer experiments in fractured rocks at two sites in Sweden     

Rune Nordqvist  Calle Hjerne  Peter Andersson 《Hydrogeology Journal》2012,20(3):519-531

As part of the Swedish site investigations and research associated with the disposal of spent nuclear fuel, tracer experiments in deep boreholes have been employed in order to characterize solute transport and hydraulic connectivity in the fractured bedrock at two sites??Forsmark and Laxemar-Simpevarp. Performance and analytical results are presented from a suite of tracer experiments in varying scales, from single-hole injection-withdrawal tests, intermediate-scale tests with sorbing tracers, to large-scale connectivity tests over distances up to several hundred meters in major fracture zones or networks of zones. In addition to demonstrating transport connectivity over large distances, a general result is that the single-hole tests, as well as the cross-hole tests with sorbing tracers, have clearly demonstrated the process of solute retention of water-conductive features in the rock at different scales.  相似文献   

The Arctic Coastal Dynamics Database: A New Classification Scheme and Statistics on Arctic Permafrost Coastlines     

Hugues Lantuit  Pier Paul Overduin  Nicole Couture  Sebastian Wetterich  Felix Aré  David Atkinson  Jerry Brown  Georgy Cherkashov  Dmitry Drozdov  Donald Lawrence Forbes  Allison Graves-Gaylord  Mikhail Grigoriev  Hans-Wolfgang Hubberten  James Jordan  Torre Jorgenson  Rune Strand ?deg?rd  Stanislav Ogorodov  Wayne H. Pollard  Volker Rachold  Sergey Sedenko  Steve Solomon  Frits Steenhuisen  Irina Streletskaya  Alexander Vasiliev 《Estuaries and Coasts》2012,35(2):383-400

Arctic permafrost coasts are sensitive to changing climate. The lengthening open water season and the increasing open water area are likely to induce greater erosion and threaten community and industry infrastructure as well as dramatically change nutrient pathways in the near-shore zone. The shallow, mediterranean Arctic Ocean is likely to be strongly affected by changes in currently poorly observed arctic coastal dynamics. We present a geomorphological classification scheme for the arctic coast, with 101,447?km of coastline in 1,315 segments. The average rate of erosion for the arctic coast is 0.5?m? year^?1 with high local and regional variability. Highest rates are observed in the Laptev, East Siberian, and Beaufort Seas. Strong spatial variability in associated database bluff height, ground carbon and ice content, and coastline movement highlights the need to estimate the relative importance of shifting coastal fluxes to the Arctic Ocean at multiple spatial scales.  相似文献   

Erratum to “Evaluating the structural character and tectonic history of the Witwatersrand Basin” [Precambrian Research 177 (2010) 1–22]     

Bjinse T. Dankert  Kim A.A. Hein 《Precambrian Research》2010

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Seismic architecture and sedimentology of a major grounding zone system deposited by the Bjørnøyrenna Ice Stream during Late Weichselian deglaciation     

Denise Christina Rüther  Rune Mattingsdal  Karin Andreassen  Matthias Forwick  Katrine Husum 《Quaternary Science Reviews》2011,30(19-20):2776-2792

A 280 km wide sediment wedge in outer Bjørnøyrenna (Bear Island Trough), south-western Barents Sea, has been investigated using 2D and 3D seismic data, sediment gravity cores, as well as regional swath and large scale bathymetry data. The bathymetry data indicate a division into an up to 35 m high frontal wedge with large depressions, and an upstream part characterized by mega scale glacial lineations (MSGL). From seismic sections increasing erosion is demonstrated for the upstream part, coinciding with the location of MSGL. Whether the latter are depositional features postdating an extensive erosional event or formed by erosion remains inconclusive. Based on the distinct morphology and internal structures, we infer that the system was deposited during a rapid readvance whereby the ice front pushed and bulldozed predominantly soft, diluted proglacial sediments. Analyses in the eastern part of the sediment system reveal the existence of imbricated thrust sheets in the frontal part of the wedge. This is suggested to imply upstream erosion of sedimentary rock and incorporation of thrusted blocks into the moraine, forming a composite ridge locally. We argue that observed large scale depressions are dead-ice features in the marine environment. It is envisioned that intense englacial thrusting may have developed into a decollement as the cold glacier snout got overrun by ice masses from the interior, thereby enabling the inclusion of slabs of ice in the push moraine mass. Radiocarbon dates indicate that the sediment wedge was deposited around 17,090 cal yrs BP (14,530 ¹⁴C yrs BP) and that the ice front probably remained stable until 16,580 cal yrs BP (13,835 ¹⁴C yrs BP).  相似文献