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  • 1. Amanda Collaboration, -
    et al.
    Pohl, Arvid
    Högskolan i Kalmar, Naturvetenskapliga institutionen.
    Optical Properties of Deep Glacial Ice at the South Pole2006Inngår i: Journal of Geophysical Research, ISSN 0148-0227, E-ISSN 2156-2202, Vol. 111, nr D13, s. D13203-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have remotely mapped optical scattering and absorption in glacial ice at the South Pole for wavelengths between 313 and 560 nm and depths between 1100 and 2350 m. We used pulsed and continuous light sources embedded with the AMANDA neutrino telescope, an array of more than six hundred photomultiplier tubes buried deep in the ice. At depths greater than 1300 m, both the scattering coefficient and absorptivity follow vertical variations in concentration of dust impurities, which are seen in ice cores from other Antarctic sites and which track climatological changes. The scattering coefficient varies by a factor of seven, and absorptivity (for wavelengths less than ∼450 nm) varies by a factor of three in the depth range between 1300 and 2300 m, where four dust peaks due to stadials in the late Pleistocene have been identified. In our absorption data, we also identify a broad peak due to the Last Glacial Maximum around 1300 m. In the scattering data, this peak is partially masked by scattering on residual air bubbles, whose contribution dominates the scattering coefficient in shallower ice but vanishes at ∼1350 m where all bubbles have converted to nonscattering air hydrates. The wavelength dependence of scattering by dust is described by a power law with exponent −0.90 ± 0.03, independent of depth. The wavelength dependence of absorptivity in the studied wavelength range is described by the sum of two components: a power law due to absorption by dust, with exponent −1.08 ± 0.01 and a normalization proportional to dust concentration that varies with depth; and a rising exponential due to intrinsic ice absorption which dominates at wavelengths greater than ∼500 nm.

  • 2.
    Burlakovs, Juris
    et al.
    University of Latvia, Latvia.
    Jani, Yahya
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Grinfelde, I.
    Latvia University of Life Sciences and Technologies, Latvia;Scientific Laboratory of Forest and Water Resources, Latvia.
    Pilecka, J.
    Latvia University of Life Sciences and Technologies, Latvia;Scientific Laboratory of Forest and Water Resources, Latvia.
    Valujeva, K.
    Latvia University of Life Sciences and Technologies, Latvia;Scientific Laboratory of Forest and Water Resources, Latvia.
    Geophysical aspects of abandoned landfill geomorphological and material properties macro-characterization2020Inngår i: International Multidisciplinary Scientific GeoConference Surveying Geology and Mining Ecology Management, SGEM, International Multidisciplinary Scientific Geoconference , 2020, Vol. 20, nr 1.2, s. 551-558Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Landfills (dumps) are places where the end of the life cycle of products can be found - useful material is dumped away from the sight creating contaminant flows around. Another problem is huge unexplored potential of resources recycling - we have limited knowledge also on useful elements and materials that are buried. The solution to overcome the limitations that provide remote sensing and traditional geodesy, proximal sensing techniques could be used. “Near surface geophysics” with operation at or just below the soil surface, significantly may contribute to give answers that traditionally are solved only after excavation. Geophysical methods are various, those can be active (i.e. create its own signal) or passive (i.e. register an existing signal); invasive (by inserting devices into the soil) or non-destructive. Some of these methods are static (e.g. a sequence of inserted electrodes), others can be used in a mobile way (e.g. pulled by a quad-bike). In general, their depth of exploration can vary from a few decimetres to some tens of metres. Thus in range of wide geophysical methodology spectrum almost all methods might be of use for unknown dump exploration depending on circumstances. In this paper, the aim is to macro-characterize anthropogenic geomorphological forms for contouring of old buried dumps by use of magnetometry, and geoelectric research methods to provide knowledge on approximate content of the dump. Protonmagnetometer was used in Eastern Latvia to determine unseen on surface dumpsite, buried in forest; induced polarisation and electric resistivity research was done in Southern Sweden for the macro-content analysis of dump hills composed of glass industry residuals and construction waste mixture. Geophysical surveying was performed to support site investigation with respect to landfill-related environmental problems, to enhance the opportunity for contouring of location of material mass and initially evaluate its physical properties. Results have shown good potential of geophysical surveying to spatially characterize landfill masses (location and dimensions) and to identify the internal structure of a landfill site, which already provides valuable information to estimate the landfill mining (material recovery) potential of landfills.

  • 3.
    Burlakovs, Juris
    et al.
    University of Latvia, Latvia.
    Valujeva, K.
    Latvia University of Life Sciences and Technologies, Latvia.
    Jani, Yahya
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Kriipsalu, M.
    Estonian University of Life Sciences, Estonia.
    Setyobudi, R. H.
    University of Muhammadiyah Malang, Indonesia.
    Magnetometry and electromagnetic screening of dumps - fast solution for geoenvironmental information aquisition2021Inngår i: 82nd EAGE Conference and Exhibition 2021, European Association of Geoscientists and Engineers, EAGE , 2021, s. 3032-3036Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Dumps and landfills are the end place of unwanted material and disposed products. Burried resources may be landfill mined and environmental pollution diminished. The problem is lack of information on unknown dump sites of former times – there remote sensing and traditional geodesy, proximal sensing techniques could be used. Near surface geophysical methods are valuable for screening of areas where drilling is limited due to technological limitations and anthropogenic unhomogenousity of material. The aim of this study was to determine whether screening of magnetometry and geoelectrical methods may be useful for old burried dumps recognition. Protonmagnetometer was used in Eastern Latvia to detect burried dump in forest, already covered by soil and vegetation. Induced polarisation and electric resistivity research was done in Southern Sweden for the macro-content analysis of dump hills composed of glass industry residuals and construction waste mixture. Surveying helped to determine macroproperties such as geomorphology and physical type of material underneath the surface. Results allowed spatially characterize dumpsite masses (location and dimensions) and identify the internal structure of a these sites. This is valuable information in order to estimate the material recovery potential of landfills.

  • 4.
    Doro, Kennedy O.
    et al.
    University of Toledo, USA.
    Kolapkar, Amar M.
    University of Toledo, USA.
    Bank, Carl-Georg
    University of Toronto, Canada.
    Wescott, Daniel J.
    Texas State University, USA.
    Mickleburgh, Hayley L.
    Linnéuniversitetet, Fakulteten för konst och humaniora (FKH), Institutionen för kulturvetenskaper (KV).
    Geophysical imaging of buried human remains in simulated mass and single graves: Experiment design and results from pre-burial to six months after burial2022Inngår i: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 335, artikkel-id 111289Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, we present an experiment design and assess the capability of multiple geophysical techniques to image buried human remains in mass and individual graves using human cadavers willingly donated for scientific research. The study is part of a novel, interdisciplinary mass grave experiment established in May 2021 which consists of a mass grave with 6 human remains, 3 individual graves and two empty control graves dug to the same size as the mass grave and individual graves. Prior to establishing the graves, we conducted background measurements of electrical resistivity tomography (ERT), electromagnetics (EM), and ground penetrating radar (GPR) while soil profiles were analyzed in situ after excavating the graves. All graves were also instrumented with soil sensors for monitoring temporal changes in soil moisture, temperature, and electrical conductivity in situ. Measurements of ERT, EM and GPR were repeated 3, 37, 71 and 185 days after burial with further repeated measurements planned for another twelve months. ERT results show an initial increase in resistivity in all graves including the control graves at 3 days after burial and a continuous decrease thereafter in the mass and individual graves with the strongest decrease in the mass grave. Conductivity distribution from the EM shows a similar trend to the ERT with an initial decrease in the first 3 days after burial. Distortion in linear reflectors, presence of small hyperbolas and isolated strong amplitude reflectors in the GPR profiles across the graves is associated with known locations of the graves. These initial results validate the capability of geoelectrical methods in detecting anomalies associated with disturbed ground and human decay while GPR though show some success is limited by the geology of the site.

  • 5.
    Ferrón, Sara
    et al.
    University of Hawai‘i at Mānoa, USA.
    Wilson, Samuel T.
    University of Hawai‘i at Mānoa, USA.
    Martínez-García, Sandra
    University of Hawai‘i at Mānoa, USA.
    Quay, Paul D.
    University of Washington, USA.
    Karl, David M.
    University of Hawai‘i at Mānoa, USA.
    Metabolic balance in the mixed layer of the oligotrophic North Pacific Ocean from diel changes in O2/Ar saturation ratios2015Inngår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 42, nr 9, s. 3421-3430Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In situ measurements were made to determine oxygen (O<inf>2</inf>) metabolic balance in the upper oligotrophic ocean from diel changes in O<inf>2</inf> to argon (Ar) ratios. The study took place during 13-24 March 2014, at the Hawaii Ocean Time-series Station ALOHA (A Long-term Oligotrophic Habitat Assessment), in the North Pacific Subtropical Gyre. Microbial community respiration and gross O<inf>2</inf> production, estimated from in situ diel changes in O<inf>2</inf>/Ar saturation, agreed well with those calculated using other independent methods. Net oxygen production (NOP), estimated from in situ diel changes in O<inf>2</inf>/Ar saturation, showed large day-to-day variability. However, when averaged over the entire observational period, mean diel NOP was in relatively good agreement with the estimated mean steady state NOP (9.2±9.3mmolO<inf>2</inf>m-2d-1 compared to 11.7±1.1mmolO<inf>2</inf>m-2d-1, respectively). Key Points Diel changes in O<inf>2</inf>/Ar were used to determine mixed layer ecosystem metabolism Estimated metabolic rates agreed well with other independent methods There was a net production of O<inf>2</inf> in the mixed layer during the sampling period.

  • 6.
    Oleschko, K.
    et al.
    National Autonomous University of Mexico, Mexico.
    Khrennikov, Andrei
    Linnéuniversitetet, Fakulteten för teknik (FTK), Institutionen för matematik (MA).
    Applications of p-adics to geophysics: Linear and quasilinear diffusion of water-in-oil and oil-in-water emulsions2017Inngår i: Theoretical and mathematical physics, ISSN 0040-5779, E-ISSN 1573-9333, Vol. 190, nr 1, s. 154-163Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In a very general setting, we discuss possibilities of applying p-adics to geophysics using a p-adic diffusion representation of the master equations for the dynamics of a fluid in capillaries in porous media and formulate several mathematical problems motivated by such applications. We stress that p-adic wavelets are a powerful tool for obtaining analytic solutions of diffusion equations. Because p-adic diffusion is a special case of fractional diffusion, which is closely related to the fractal structure of the configuration space, p-adic geophysics can be regarded as a new approach to fractal modeling of geophysical processes.

  • 7.
    Peltola, Pasi
    et al.
    Högskolan i Kalmar, Naturvetenskapliga institutionen.
    Åström, Mats
    Högskolan i Kalmar, Naturvetenskapliga institutionen.
    Urban geochemistry: a multimedia and multielement survey of a northern small-town urban area2003Inngår i: Environmental Geochemistry and Health, ISSN 0269-4042, Vol. 25, nr 4, s. 397-419Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The concentrations and distributions of chemical elements (Ag, Al, As, Au, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Ga, Hg, K, La,Mg,Mn,Mo, Na,Ni, P, Pb, S, Sb, Sc, Se, Sr, Te, Th, Ti, Tl,U, V, Wand Zn) were studied in till, humus and urban soil in Jakobstad, a small town (20,000 inhabitants)in W. Finland. The analyses were performed with ICP-MS after aqua regia leaching of till (n = 37), urban topsoil (n = 32) and subsoil (n = 32), and HNO3 leaching of humus (n = 37). The till and humus samples, collected at the same sites, were divided into urban and rural samples. The urban till was not significantly enriched in metals. In contrast, a majority of the elements occurred in higher concentrations in the urban than the rural humus samples. Statistical and spatial interpretations of the humus data revealed that traffic (Pb, V and Ni), metal industry (Pb, Zn, Bi, Sb and Cr), an abandoned shooting range (Pb and Sb) and other sources contribute to higher metal levels in the urban humus. The urban soil samples were collected at parks, yards, abandoned industrial sites, roadsides, etc. The topsoil samples were enriched in most elements, also by elements not enriched in the urban humus (e.g. Cd). At several sites, the concentrations far exceeded the limit concentrations for contaminatedsoils in Finland. A large variety of sources were identified or indicated. 

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