Timing and maximum flood level of the Early Holocene glacial lake Nedre Glomsjø outburst flood,Norway     

Fredrik Høgaas  Louise Hansen  Ivar Berthling  Martin Klug  Oddvar Longva  Helle Daling Nannestad  Lars Olsen  Anders Romundset 《Boreas: An International Journal of Quaternary Research》2023,52(3):295-313

This study discusses the timing and maximum flood level of the Nedre Glomsjø outburst flood, Norway, based on sediment records retrieved from 15 bog and lake basins located close to the purported maximum flooded level. The sediment records in 12 of the basins consist of a distinct light-coloured silty bed that is correlated to the outburst-flood-deposited ‘Romerike Silt Bed’ identified elsewhere in the region. The silt bed is recorded in basins up to a certain elevation and is absent above this level. The new maximum flood level inferred from the basin sediment records exceeds the established landform-induced palaeostage indicators by 5–10 m. The data indicate a higher maximum flood level and larger inundation area than previously suggested and highlight the importance of acquiring a wide range of geological data when reconstructing palaeofloods. Radiocarbon dates of terrestrial macrofossils found stratigraphically above and below the Romerike Silt Bed suggest that the glacial lake Nedre Glomsjø outburst flood occurred between 10.5 and 10.3 cal. ka BP. The new and well-constrained timing of the outburst flood is beneficial for reconstructing regional deglaciation and provides a precise age for the Romerike Silt Bed chronostratigraphical marker, which is of value for studies in SE Norway and adjacent regions.  相似文献   

The Characteristics of Solar X-Class Flares and CMEs: A Paradigm for Stellar Superflares and Eruptions?     

Louise K. Harra  Carolus J. Schrijver  Miho Janvier  Shin Toriumi  Hugh Hudson  Sarah Matthews  Magnus M. Woods  Hirohisa Hara  Manuel Guedel  Adam Kowalski  Rachel Osten  Kanya Kusano  Theresa Lueftinger 《Solar physics》2016,291(6):1761-1782

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Preface: Probing the Sun Inside and Out     

Louise Harra  Deborah Baker  Rachel Howe  John Leibacher  Lidia van Driel-Gesztelyi 《Solar physics》2015,290(11):3091-3094

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Rising to the challenge of environmental behaviour change: Developing a reflexive diary approach     

Louise Reid  Colin Hunter  Philip W. Sutton 《Geoforum》2011,42(6):720-730

The relationship between expressed attitudes and actual behaviour in the context of sustainable development is complex and difficult to apply in a policy-relevant manner. The household, however, represents a key ‘lens’ for understanding the environmental impact of consumption patterns and for instigating policy designed to change consumer behaviour. This paper assesses the use of a household diary approach as a means of framing and collecting household environmental data, and, critically, as an educational vehicle for bringing about behavioural change by encouraging reflexivity. Evaluating the success of the diary approach at instigating behavioural change, the paper concludes that the diary approach: (1) created awareness about pro-environmental behaviour where there was none; (2) extended existing awareness to a wider range of pro-environmental behaviours and range of household members, and; (3) induced change in pro-environmental behaviour. In particular, the paper argues that current research neglects the potential that participating in the research process may contribute to changing the outlook or behaviour of participants.  相似文献   

Sedimentology of a wreck: the Rainbow Warrior revisited     

Smith AM  Kregting L  Fern S  Fraser CI 《Marine pollution bulletin》2011,62(11):2412-2419

The wreck of the Rainbow Warrior, a 40-m ship sunk on 12 December 1987 in Matauri Bay (34° 59′ S, 173° 56′ E), Cavalli Islands, northeastern New Zealand, offers an opportunity to investigate the impact of artificial substrate on temperate carbonate sedimentation. Surface sediment samples showed no significant textural or compositional difference between sediments near the wreck and those far from it. The large and diverse carbonate-producing community resident on the wreck (dominated by bryozoans, corals and sponges) has not had a measurable influence on adjacent bottom sediments (dominated by bivalves and barnacles), even after 21 years. It is likely that carbonate production on the Rainbow Warrior is insufficient to leave any sedimentary record over the potential lifetime of the wreck on the seafloor, which informs our understanding of the long-term impacts of shipwrecks (and other artificial substrata) on the local benthic environment in shallow temperate ecosystems.  相似文献   

Neo-assimilationist citizenship and belonging policies in Britain: Meanings for transnational migrants in northern England     

Louise Waite 《Geoforum》2012,43(2):353-361

The overall aim of this paper is to contribute to debates on the relationships between citizenship and migration in the UK context in the light of recent changes in UK immigration policy. In particular, it focuses on the question of what an increasingly neo-assimilationist state articulation of national belonging means for transnational migrants living in Britain. The paper begins by charting the evolving nature of citizenship conceptualisations in Western neoliberal contexts and illustrates how Britain has responded to this shifting landscape. The context is one of enhanced ‘migration securitization’ wherein the state implies that the integrity of the nation state and its security can only be assured if migration flows and migrants themselves are closely controlled and monitored. This has led to Britain attempting to bolster the formal institution of citizenship (with its attendant rights and responsibilities) and tie it more explicitly to notions of belonging to the nation. Through research with national/regional policy officials and migrant organisations this paper firstly examines the political landscape of citizenship and belonging in Britain as it relates to migrants. Secondly, it draws on research with African transnational migrants in northern England to explore their senses of belonging and ask whether these cohere with the described state discourse or whether their feelings of belonging exist in tension with neo-assimilationist policies designed to promote a core national identity.  相似文献   

Transequatorial Filament Eruption and Its Link to a Coronal Mass Ejection   总被引：3，自引：0，他引：3  

Louise K. Harra 《中国天文和天体物理学报》2006,6(2):247-259

We revisit the Bastille Day flare/CME Event of 2000 July 14, and demonstrate that this flare/CME event is not related to only one single active region (AR). Activation and eruption of a huge transequatorial filament are seen to precede the simultaneous filament eruption and flare in the source active region, NOAA AR 9077, and the full halo-CME in the high corona. Evidence of reconfiguration of large-scale magnetic structures related to the event is illustrated by SOHO EIT and Yohkoh SXT observations, as well as, the reconstructed 3D magnetic lines of force based on the force-free assumption. We suggest that the AR filament in AR9077 was connected to the transequatorial filament. The large-scale magnetic composition related to the transequatorial filament and its sheared magnetic arcade appears to be an essential part of the CME parent magnetic structure. Estimations show that the filament-arcade system has enough magnetic helicity to account for the helicity carried by the related CMEs. In addition, rather global magnetic connectivity, covering almost all the visible range in longitude and a huge span in latitude on the Sun, is implied by the Nancay Radioheliograph (NRH) observations. The analysis of the Bastille Day event suggests that although the triggering of a global CME might take place in an AR, a much larger scale magnetic composition seems to be the source of the ejected magnetic flux, helicity and plasma. The Bastille Day event is the first described example in the literature, in which a transequatorial filament activity appears to play a key role in a global CME. Many tens of halo-CME are found to be associated with transequatorial filaments and their magnetic environment.  相似文献   

A possible contribution to CMB anisotropies at high ℓ from primordial voids     

Louise M. Griffiths  Martin Kunz  Joseph Silk 《Monthly notices of the Royal Astronomical Society》2003,339(3):680-684

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The effect of reionization on the COBE normalization     

Louise M. Griffiths  Andrew R. Liddle 《Monthly notices of the Royal Astronomical Society》2001,324(3):769-771

We point out that the effect of reionization on the microwave anisotropy power spectrum is not necessarily negligible on the scales probed by COBE . It can lead to an upward shift of the COBE normalization by more than the 1 σ error quoted, ignoring reionization. We provide a fitting function to incorporate reionization into the normalization of the matter power spectrum.  相似文献   

Mixed messages in iron oxide–copper–gold systems of the Cloncurry district,Australia: insights from PIXE analysis of halogens and copper in fluid inclusions     

Timothy Baker  Roger Mustard  Bin Fu  Patrick J. Williams  Guoyi Dong  Louise Fisher  Geordie Mark  Chris G. Ryan 《Mineralium Deposita》2008,43(6):599-608

Proterozoic rocks of the Cloncurry district in NW Queensland, Australia, are host to giant (tens to hundreds of square kilometers) hydrothermal systems that include (1) barren regional sodic–calcic alteration, (2) granite-hosted hydrothermal complexes with magmatic–hydrothermal transition features, and (3) iron oxide–copper–gold (IOCG) deposits. Fluid inclusion microthermometry and proton-induced X-ray emission (PIXE) show that IOCG deposits and the granite-hosted hydrothermal complexes contain abundant high temperature, ultrasaline, complex multisolid (type 1) inclusions that are less common in the regional sodic–calcic alteration. The latter is characterized by lower salinity three-phase halite-bearing (type 2) and two-phase (type 3) aqueous inclusions. Copper contents of the type 1 inclusions (>300 ppm) is higher than in type 2 and 3 inclusions (<300 ppm), and the highest copper concentrations (>1,000 ppm) are found both in the granite-hosted systems and in inclusions with Br/Cl ratios that are consistent with a magmatic source. The Br/Cl ratios of the inclusions with lower Cu contents are consistent with an evaporite-related origin. Wide ranges in salinity and homogenization temperatures for fluid inclusions in IOCG deposits and evidence for multiple fluid sources, as suggested by halogen ratios, indicate fluid mixing as an important process in IOCG genesis. The data support both leaching of Cu by voluminous nonmagmatic fluids from crustal rocks, as well as the direct exsolution of Cu-rich fluids from magmas. However, larger IOCG deposits may form from magmatic-derived fluids based on their higher Cu content.  相似文献