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  • 1.
    Abrate, Matteo
    et al.
    CNR Natl Res Council, Inst Informat & Telemat, I-56124 Pisa, Italy.
    Bacciu, Clara
    CNR Natl Res Council, Inst Informat & Telemat, I-56124 Pisa, Italy.
    Hast, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction. CNR Natl Res Council, Inst Informat & Telemat, I-56124 Pisa, Italy.
    Marchetti, Andrea
    CNR Natl Res Council, Inst Informat & Telemat, I-56124 Pisa, Italy.
    Minutoli, Salvatore
    CNR Natl Res Council, Inst Informat & Telemat, I-56124 Pisa, Italy.
    Tesconi, Maurizio
    CNR Natl Res Council, Inst Informat & Telemat, I-56124 Pisa, Italy.
    Geomemories - A Platform for Visualizing Historical, Environmental and Geospatial Changes of the Italian Landscape2013In: ISPRS International Journal of Geo-Information. Special issue: Geospatial Monitoring and Modelling of Environmental Change, ISSN 2220-9964, Vol. 2, no 2, p. 432-455Article in journal (Refereed)
    Abstract [en]

    The GeoMemories project aims at publishing on the Web and digitally preserving historical aerial photographs that are currently stored in physical form within the archives of the Aerofototeca Nazionale in Rome. We describe a system, available at http://www.geomemories.org, that lets users visualize the evolution of the Italian landscape throughout the last century. The Web portal allows comparison of recent satellite imagery with several layers of historical maps, obtained from the aerial photos through a complex workflow that merges them together. We present several case studies carried out in collaboration with geologists, historians and archaeologists, that illustrate the great potential of our system in different research fields. Experiments and advances in image processing technologies are envisaged as a key factor in solving the inherent issue of vast amounts of manual work, from georeferencing to mosaicking to analysis.

  • 2. Adinugroho, Sigit
    et al.
    Vallot, Dorothée
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Westrin, Pontus
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Strand, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction.
    Calving events detection and quantification from time-lapse images in Tunabreen glacier2015In: Proc. 9th International Conference on Information & Communication Technology and Systems, Piscataway, NJ: IEEE , 2015, p. 61-65Conference paper (Refereed)
  • 3.
    Adrian, Lindqvist
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Koppling av grundvattenmodell och jordmodell med en geoteknisk sättningsmodell2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    From a construction engineering point of view groundwater drawdown in a confined aquifer can result in ground subsidence that can damage buildings and constructions. The connection between hydrogeology and soil mechanics is clear, however when estimating ground settlement as a result of groundwater drawdown the estimations are often rough. This is due to that settlement is traditionally calculated with methods that only allow calculations in single points where geotechnical data is estimated. Areas between these points are often left out of the calculations. Groundwater drawdown is seldom simulated with acknowledged software programs like Modflow when estimating groundwater lowering and the affected area.This study combines a groundwater model simulated in Modflow and a soil strata model, interpolated with Kriging, with settlement calculations. This ends up as a an integrated soil settlement model which has the purpose to generate overview maps over areas that are sensitive to settlement as a result of ground water lowering. The integrated model is programmed in Octave for this study. The model is then tested with a case study that uses data from a real construction project in the area of Mälardalen. A hypothetical case of ground water lowering is simulated for the case study. Fundamental hydro-geological theory is used to estimate loads and effective stresses from the lowering of the water table.The result from the integrated model has been validated against calculations of settlement in the software Geosuite Settlement which is an acknowledged method for settlement calculations. This shows that the integrated model calculates settlement with great precision. The modeled initial ground water table is compared with a kriginginterpolated groundwater table which is based on data from ground water pipes in the area. Based on the comparison the initial ground water conditions simulated in Modflow are accepted. This simulated ground water model has the soil model and also a water balance integrated.The results from the case study show that unexpectedly large ground settlements can occur even far from the source of the ground water lowering.For the case study three different soil models are used, both in the ground water model and in the integrated model. The soil models differ in a way that they are based on different amounts of data from which the kriging interpolation is done. The purpose for this is to investigate what effects this might have on the ground water model and the integrated model respectively. The results from these different simulations show insignificantly small differences.

  • 4.
    Ahrens, Lutz
    et al.
    Swedish Univ Agr Sci SLU, Dept Aquat Sci & Assessment, Box 7050, SE-75007 Uppsala, Sweden..
    Gashaw, Habiba
    Univ Addis Ababa, Ethiopian Inst Water Resources, Addis Ababa, Ethiopia..
    Sjöholm, Margareta
    Swedish Univ Agr Sci SLU, Dept Aquat Sci & Assessment, Box 7050, SE-75007 Uppsala, Sweden..
    Gebrehiwot, Solomon Gebreyohannis
    Univ Addis Ababa, Ethiopian Inst Water Resources, Addis Ababa, Ethiopia..
    Getahun, Abebe
    Univ Addis Ababa, Dept Zool Sci, Addis Ababa, Ethiopia.;Hawassa Univ, Dept Biol, POB 5, Hawassa, Ethiopia..
    Derbe, Ermias
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Hawassa Univ, Dept Biol, POB 5, Hawassa, Ethiopia..
    Bishop, Kevin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Swedish Univ Agr Sci SLU, Dept Aquat Sci & Assessment, Box 7050, SE-75007 Uppsala, Sweden..
    Åkerblom, Staffan
    Swedish Univ Agr Sci SLU, Dept Aquat Sci & Assessment, Box 7050, SE-75007 Uppsala, Sweden..
    Poly- and perfluoroalkylated substances (PFASs) in water, sediment and fish muscle tissue from Lake Tana, Ethiopia and implications for human exposure2016In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 165, p. 352-357Article in journal (Refereed)
    Abstract [en]

    Lake Tana is Ethiopia's largest lake and there are plans to increase the harvest of fish from the lake. The objective of this study was to assess the levels of poly- and perfluoroalkyl substances (PFASs) in different compartments of the lake (water, sediment, and fish muscle tissue), and its implications for human exposure. The results showed higher PFAS concentrations in piscivorous fish species (Labeobarbus mega-stoma and Labeobarbus gorguari) than non-piscivorous species (Labeobarbus intermedius, Oreochromis niloticus and Clarias gariepinus) and also spatial distribution similarities. The Sigma PFAS concentrations ranged from 0.073 to 5.6 ng L-1 (on average, 2.9 ng L-1) in surface water, 0.22-0.55 ng g(-1) dry weight (dw) (on average, 0.30 ng g(-1) dw) in surface sediment, and non-detected to 5.8 ng g(-1) wet weight (ww) (on average, 1.2 ng g(-1) ww) in all fish species. The relative risk (RR) indicates that the consumption of fish contaminated with perfiuorooctane sulfonate (PFOS) will likely not cause any harmful effects for the Ethiopian fish eating population. However, mixture toxicity of the sum of PFASs, individual fish consumption patterns and increasing fish consumption are important factors to consider in future risk assessments.

  • 5. Albani, S
    et al.
    Mahowald, N M
    Winckler, G
    Anderson, R F
    Bradtmiller, L I
    Delmonte, B
    François, R
    Goman, M
    Heavens, N G
    Hesse, P P
    Hovan, S A
    Kang, S G
    Kohfeld, K E
    Lu, H
    Maggi, V
    Mason, A
    Mayewski, P A
    McGee, D
    Miao, X
    Otto-Bliesner, L
    Perry, A T
    Pourmand, A
    Roberts, H M
    Rosenbloom, N
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Sun, J
    Twelve thousand years of dust: the Holocene global dust cycle constrained by natural archives2015In: Climate of the Past, ISSN 1814-9324, E-ISSN 1814-9332, Vol. 11, no 6, p. 869-903Article in journal (Refereed)
    Abstract [en]

    Mineral dust plays an important role in the climate system by interacting with radiation, clouds, and biogeochemical cycles. In addition, natural archives show that the dust cycle experienced variability in the past in response to global and local climate change. The compilation of the DIRTMAP paleodust datasets in the last two decades provided a target for paleoclimate models that include the dust cycle, following a time slice approach. We propose an innovative framework to organize a paleodust dataset that moves on from the positive experience of DIRTMAP and takes into account new scientific challenges, by providing a concise and accessible dataset of temporally resolved records of dust mass accumulation rates and particle grain-size distributions. We consider data from ice cores, marine sediments, loess/paleosol sequences, lake sediments, and peat bogs for this compilation, with a temporal focus on the Holocene period. This global compilation allows investigation of the potential, uncertainties and confidence level of dust mass accumulation rates reconstructions, and highlights the importance of dust particle size information for accurate and quantitative reconstructions of the dust cycle. After applying criteria that help to establish that the data considered represent changes in dust deposition, 43 paleodust records have been identified, with the highest density of dust deposition data occurring in the North Atlantic region. Although the temporal evolution of dust in the North Atlantic appears consistent across several cores and suggest that minimum dust fluxes are likely observed during the Early to mid-Holocene period (6000–8000 years ago), the magnitude of dust fluxes in these observations is not fully consistent, suggesting that more work needs to be done to synthesize datasets for the Holocene. Based on the data compilation, we used the Community Earth System Model to estimate the mass balance and variability of the global dust cycle during the Holocene, with dust load ranging from 17.1 to 20.5 Tg between 2000 and 10 000 years ago, and a minimum in the Early to Mid-Holocene (6000–8000 years ago).

  • 6.
    Anderson, Kevin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Uppsala Centre for Sustainable Development, CSD Uppsala. Univ Manchester, Tyndall Ctr, Manchester M13 9PL, Lancs, England..
    Peters, Glen
    CICERO, Pb 1129 Blindern, N-0318 Oslo, Norway..
    The trouble with negative emissions2016In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 354, no 6309, p. 182-183Article in journal (Other academic)
  • 7.
    Andersson, Andreas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Department of Ecotechnology and Sustainable Building Engineering, Mid Sweden University, Östersund, Sweden.
    Falck, Eva
    Sjöblom, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Department of Arctic Geophysics, University Centre in Svalbard, Longyearbyen, Norway.
    Kljun, Natascha
    Sahlée, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Omar, Abdirahaman
    Rutgersson, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Air-sea gas transfer in high Arctic fjords2017In: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 44, no 5, p. 2519-2526Article in journal (Refereed)
    Abstract [en]

    In Arctic fjords and high-latitude seas, strong surface cooling dominates during a large part of the year, generating water-side convection (w*w) and enhanced turbulence in the water. These regions are key areas for the global carbon cycle; thus, a correct description of their air-sea gas exchange is crucial. CO2-data were measured via the eddy covariance technique in marine Arctic conditions and reveal that water-side convection has a major impact on the gas transfer velocity. This is observed even at wind speeds as high as 9 m s-1, where convective motions are generally thought to be suppressed by wind-driven turbulence. The enhanced air-sea transfer of CO2 caused by water-side convection nearly doubled the CO2uptake, after scaled to open sea conditions the contribution from  to the CO2 flux remained as high as 34%; this phenomenon is expected to be highly important for the total carbon uptake in marine Arctic areas.

  • 8.
    Andersson Cada, Emil
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Grundvattenpotential i Västerviks kommun: Geostatistiska metoder i en GIS-miljö2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this study, groundwater resource potential (GRP) for Västervik municipality has been investigated using the methodology developed in the article by Earon et al. (2015). The aim was to test the reliability of the methodology for groundwater mapping, as to further add to the knowledge base of groundwater access. The GRP-methodology is a linear additive multicriteria analysis where geohydrological indicators are scored, classified into groups, then multiplied by weights calculated using Principal Component Analysis (PCA). The classification and validation were performed against specific capacity [L/(h*m)], which is a well's capacity calculated at drilling, per meter well. GRP was calculated in different sets based on 13 geohydrological variables such as altitude and Topographic Wetness Index (TWI). The results included correlation tests for Kendall's tau (0.06-0.13), Spearmans rho (0.09-0.19) with a total accuracy of 52-55%. Positive but low values ​​for Cohen´s kappa indicated that all calculations performed better than a random generator, but not by margin. Calculations of VIP (Variables importance on PLS projection), based on Partial Least Squares (PLS), identified Altitude, Earth type, Drainage density and TWI as the most influential indicators for the analysis.The conclusions of this study were, among other things, that the GRP methodology had low predictivity due to the weak relationships between the indicators and the specific capacity. The weaknesses could also be due to the fact that specific capacity has weaknesses as a validation variable for groundwater resource potential linked to uncertainties of the capacity measured at wellbore. The study shows that further development of the weighting scheme by integrating PLS would be beneficial, as PLS calculates the variance of the indicators based on the specific capacity, instead of assuming it as a PCA. 

  • 9.
    Andren, Elinor
    et al.
    Sodertom Univ, Sch Nat Sci Technol & Environm Studies, Huddinge, Sweden..
    Klimaschewski, Andrea
    Queens Univ Belfast, Sch Geog Archaeol & Palaeoecol, Belfast BT7 1NN, Antrim, North Ireland..
    Self, Angela E.
    Nat Hist Museum, Dept Life Sci, London SW7 5BD, England..
    Amour, Natalie St.
    Univ Western Ontario, Dept Earth Sci, London, ON, Canada..
    Andreev, Andrei A.
    Univ Cologne, Inst Geol & Mineral, D-50931 Cologne, Germany.;Kazan Fed Univ, Inst Geol & Petr Technol, Kazan, Russia..
    Bennett, Keith D.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Queens Univ Belfast, Sch Geog Archaeol & Palaeoecol, Belfast BT7 1NN, Antrim, North Ireland..
    Conley, Daniel J.
    Lund Univ, Dept Geol, Quaternary Sci, Lund, Sweden..
    Edwards, Thomas W. D.
    Univ Waterloo, Dept Earth & Environm Sci, Waterloo, ON N2L 3G1, Canada..
    Solovieva, Nadia
    Kazan Fed Univ, Inst Geol & Petr Technol, Kazan, Russia.;UCL, Dept Geog, London WC1E 6BT, England..
    Harnmarlund, Dan
    Lund Univ, Dept Geol, Quaternary Sci, Lund, Sweden..
    Holocene climate and environmental change in north-eastern Kamchatka (Russian Far East), inferred from a multi-proxy study of lake sediments2015In: Global and Planetary Change, ISSN 0921-8181, E-ISSN 1872-6364, Vol. 134, p. 41-54Article in journal (Refereed)
    Abstract [en]

    A sediment record from a small lake in the north-eastern part of the Kamchatka Peninsula has been investigated in a multi-proxy study to gain knowledge of Holocene climatic and environmental change. Pollen, diatoms, chironomids and selected geochemical parameters were analysed and the sediment record was dated with radiocarbon. The study shows Holocene changes in the terrestrial vegetation as well as responses of the lake ecosystern to catchment maturity and multiple stressors, such as climate change and volcanic eruptions. Climate change is the major driving force resulting in the recorded environmental changes in the lake, although recurrent tephra deposition events also contributed. The sediment record has an age at the base of about 10,000 cal yrs BP, and during the first 400 years the climate was cold and the lake exhibited extensive ice-cover during winter and relatively low primary production. Soils in the catchment were poor with shrub alder and birches dominating the vegetation surrounding the lake. At about 9600-8900 cal yrs BP the climate was cold and moist, and strong seasonal wind stress resulted in reduced ice-cover and increased primary production. After ca. 8900 cal yrs BP the forest density increased around the lake, runoff decreased in a generally drier climate resulting in decreased primary production in the lake until ca. 7000 cal yrs BP. This generally dry climate was interrupted by a brief climatic perturbation, possibly attributed to the 8.2 ka event, indicating increasingly windy conditions with thick snow cover, reduced ice-cover and slightly elevated primary production in the lake. The diatom record shows maximum thermal stratification at ca. 6300-5800 cal yrs BP and indicates together with the geochemical proxies a dry and slightly warmer climate resulting in a high productive lake. The most remarkably change in the catchment vegetation occurred at ca. 4200 cal yrs BP in the form of a conspicuous increase in Siberian dwarf pine (Pinus pumila), indicating a shift to a cooler climate with a thicker and more long-lasting snow cover. This vegetational change was accompanied by marked shifts in the diatom and chironomid stratigraphies, which are also indicative of colder climate and more extensive ice-cover.

  • 10.
    Ansnaes, Karl-Markus
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Falu gruva och hållbar utveckling2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Falu Copper Mine and Sustainable Development

    Karl-Markus Ansnaes

    Falu copper mine was Sweden’s oldest mine industry which lasted for almost a thousand years. Throughout the history its area has been vastly contaminated by sulfur oxide. The contaminations has created the mining area to an environmental risk zone which has the ability to spread out into the Falu River. The river has its connections to the Dal River which is discharging towards its mouth in the Baltic Sea. In the year 1968 the first measurement from the polluted Falu River took place. Its metal content came from the mining area, although the decontamination expenses were too high for the running company Stora Kopparbergs Bergsslag AB to pay which then led to conflicts with the Environmental Protection Agency of Sweden on terms none of them could agree on. It was not until the year 1983 when they both agreed on a cooperation which contained of continuing measurements until a suffi-cient decontamination method could be applied. The cooperation was named Projekt Falu gruva. The first obligation was to improve the sewage plant in Främby by con-necting the contaminated water from the mining area with the waste water though a chemical treatment. In the year 1987 the treatment successfully began and the same year the Swedish government financed a delegation, called Dalälvsdelegationen, and its purpose was to decontaminate the pollutions along the Dal River. The delegation’s research led to three reports which contained the areas involved in the river’s pollu-tion as well how the mining area would be treated. In 1992 the Country Administra-tive Board of Dalarna, the Environmental Authority of Falun Municipality, the Environ-mental Protection Agency of Sweden and Stora Kopparbergs Bergsslag AB began cooperation in order to treat the polluted area of Falu copper mine. This cooperation became a project called Faluprojektet. The project consisted of three decontamina-tion priorities with different treatments in the area. The first decontamination priority resulted in a reducing amount of the polluted mining water by 80 % in the Falu River. The second and the third decontamination priorities had some issues during its treat-ment due to new environmental laws influenced in 1999 and the recognition from UNESCO as this area was since 2001 a world cultural heritage. Both the law and the recognition stated that it was forbidden to remove the waste on the ground from the area since it was a part of the cultural protection. This meant the waste was removed closer to the mine pit and became part of a slower and natural hydrological treatment which caused the sulfur dioxide penetrating into the ground. By doing this type pf treatment it reflects upon the environmental quality goals which Sweden is aiming for in order to reach for sustainable development.

  • 11.
    Ardakani, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Makrofossilanalys av en järnåldersboplats i Gamla Uppsala2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There have been several excavations in Old Uppsala over the years and decades since the area has been inhabited since the Iron Age. The most recent excavation took place in connection with the construction of a railway tunnel, which is a part of the East Link project. The object of an archaeological excavation is to obtain information about the way in which previous civilizations lived in a specific location, what kind of crops were cultivated, what kind of tool were being used, and so forth. In order to obtain information about prehistoric settlements, archaeologists use a variety of different methods. One of these methods is called macrofossil analysis. By using macrofossil analysis, seeds and cereals, in the shape of macrofossils, can be extracted from soil samples. By analysing macrofossils, it is possible to obtain information about buildings and thereby establishing their purposes, for instance residence, barn, and so forth. In this thesis work, macrofossil analysis was used as a way to establish the different functions of three buildings from an Iron Age settlement in Old Uppsala.

  • 12.
    Arellano, Santiago
    et al.
    Department of Earth and Space Sciences, Chalmers University of Technology, Gothenburg, Sweden.
    Yalire, M.
    Observatoire Volcanologique de Goma, Centre de Recherche en Sciences Naturelles, Lwiro, Democratic Republic of the Congo.
    Galle, Bo
    Department of Earth and Space Sciences, Chalmers University of Technology, Gothenburg, Sweden.
    Bobrowski, M.
    Institute of Environmental Physics, Heidelberg University, Heidelberg, Germany.
    Dingwell, Adam
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Johansson, M.
    Department of Earth and Space Sciences, Chalmers University of Technology, Gothenburg, Sweden.
    Norman, P.
    Department of Earth and Space Sciences, Chalmers University of Technology, Gothenburg, Sweden.
    Long-term monitoring of SO2 quiescent degassing from Nyiragongo’s lava lake2017In: Journal of African Earth Sciences, ISSN 0899-5362, Vol. 134, p. 866-873Article in journal (Refereed)
    Abstract [en]

    The activity of open-vent volcanoes with an active lava-lake, such as Nyiragongo, is characterized by persistent degassing, thus continuous monitoring of the rate, volume and fate of their gas emissions is of great importance to understand their geophysical state and their potential impact. We report results of SO2 emission measurements from Nyiragongo conducted between 2004 and 2012 with a network of ground-based scanning-DOAS (Differential Optical Absorption Spectroscopy) remote sensors. The mean SO2 emission rate is found to be 13 ± 9 kg s−1, similar to that observed in 1959. Daily emission rate has a distribution close to log-normal and presents large inter-day variability, reflecting the dynamics of percolation of magma batches of heterogeneous size distribution and changes in the effective permeability of the lava lake. The degassed S content is found to be between 1000 and 2000 ppm from these measurements and the reported magma flow rates sustaining the lava lake. The inter-annual trend and plume height statistics indicate stability of a quiescently degassing lava lake during the period of study.

  • 13.
    Bajdek, Piotr
    et al.
    Aleja Najswietszej Maryi Panny 20-20A, PL-42200 Czestochowa, Poland..
    Owocki, Krzysztof
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Sennikov, Andrey G.
    Russian Acad Sci, Borissiak Paleontol Inst, Profsoyuznaya 123, Moscow 117997, Russia.;Kazan Fed Univ, Kremlyovskaya 18, Kazan 420008, Russia..
    Golubev, Valeriy K.
    Russian Acad Sci, Borissiak Paleontol Inst, Profsoyuznaya 123, Moscow 117997, Russia.;Kazan Fed Univ, Kremlyovskaya 18, Kazan 420008, Russia..
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Residues from the Upper Permian carnivore coprolites from Vyazniki in Russia - key questions in reconstruction of feeding habits2017In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 482, p. 70-82Article in journal (Refereed)
    Abstract [en]

    Residues of twenty-five coprolite fragments collected from the Upper Permian of Vyazniki (European Russia) were studied in detail. The phosphatic composition, general shape and size, and bone inclusions of these specimens indicate that medium to large-sized carnivores, such as therocephalian therapsids or early archosauriforms, were the most likely coprolite producers. The contents of the examined fossils (i.e. Scale, bone and tooth fragments, mineral grains, and microbial structures) do not differ significantly among the samples, implying fairly comparable feeding habits of their producers. Fragments of large tooth crowns in two of the analyzed samples imply that either (1) the coprolite producer swallowed the cranial elements of its prey or (2) the coprolite producer broke and swallowed its own tooth while feeding (such tooth damage is known in archosaurs that have tooth replacement, e.g. crocodiles and dinosaurs). Indeed, the most complete tooth fragment in these fossils is serrated, most likely belonging to an early archosauriform known from skeletal records from the Late Permian of Vyaznilci. Another coprolite fragment contains the etched tooth of a lungfish, while putative actinopterygian fish remains (scales and small fragments of bones) are abundant in some samples. Mineral particles (mostly quartz grains, feldspars and mica) may have been swallowed accidentally. The preserved microbial colonies (mineralized fossil fungi and bacteria or their pseudomorphs), manifested in the coprolites as Fe-rich mineral structures, seem to have developed on the expelled feces rather than on the items before they were swallowed.

  • 14.
    Balashova, Anna
    et al.
    Swiss Fed Inst Technol, Dept Earth Sci, Inst Geochem & Petrol, Sonneggstr 5, CH-8092 Zurich, Switzerland.
    Mattsson, Hannes B.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Swiss Fed Inst Technol, Dept Earth Sci, Inst Geochem & Petrol, Sonneggstr 5, CH-8092 Zurich, Switzerland.
    Hirt, Ann M.
    Swiss Fed Inst Technol, Dept Earth Sci, Inst Geophys, Sonneggstr 5, CH-8092 Zurich, Switzerland.
    New tephrostratigraphic data from Lake Emakat (northern Tanzania): Implications for the eruptive history of the Oldoinyo Lengai volcano2018In: Journal of African Earth Sciences, ISSN 1464-343X, E-ISSN 1879-1956, Vol. 147, p. 374-382Article in journal (Refereed)
    Abstract [en]

    The northern Tanzanian sector of the Gregory Rift is an area of an active continental rifting, in which sedimentation processes are strongly affected by volcanism. Due to limited stratigraphic exposure, the volcanic record of the region is rather sparse, and assigning volcanic centres for the individual eruptions is difficult. This study presents new data on the tephrostratigraphy of the sedimentary sequence of Lake Emakat, Empakaai Crater, northern Tanzania. Seven volcanic ash layers are identified and described from a 1.1-m core of lake sediments. Geochemical, mineralogical, petrographic and magnetic analyses show that: (1) all ash layers are products of highly explosive eruptions of melilite-bearing magmas; (2) most of the eruptions originate from a complex magmatic system; (3) all ash horizons are very well preserved in the lake environment; and (4) there are significant fluctuations of the bulk magnetic susceptibility of the lacustrine sediments which is related to microtephra from additional eruptions, the result of detritus, washed from the shore during periods of strong lake level fluctuations or periods of high erosion rates, or simply by the contamination by the material from the ash layers. Based on geochemistry and mineralogy of the seven identified ash layers in Lake Emakat, combined with the eruption ages from C-14 datings, we can pinpoint Oldoinyo Lengai volcano as the source of these specific layers. The combination of this new data with existing chronological data from Ryner et al. (2007), retrieved from the same core, provides precise ages of the voluminous highly explosive eruptions in this region of East Africa during the Pleistocene-Holocene transition.

  • 15.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Denchik, Nataliya
    Univ Montpellier 2, Geosci Montpellier CNRS UMR 5243, Cc 060 Bat 22,Pl Eugene Bataillon, F-34095 Montpellier 05, France..
    Pezard, Philippe A.
    Univ Montpellier 2, Geosci Montpellier CNRS UMR 5243, Cc 060 Bat 22,Pl Eugene Bataillon, F-34095 Montpellier 05, France..
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Numerical modelling of CO2 injection at small-scale field experimental site in Maguelone, France2016In: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 54, p. 200-210Article in journal (Refereed)
    Abstract [en]

    To evaluate the performance of downhole and surface geophysical monitoring methods, a series of shallow gas injection-monitoring experiments has been performed in a coastal saline aquifer at Maguelone, France. The recorded data include pressure measurements with a Westbay multilevel completion and CO2 saturation at an observation well derived from electrical resistivity with a modified Waxman-Smits (MWS) model. In this work, the aim is to develop a simulation model capturing the gas transport behavior and consistent with field data. For this purpose, the simulation of the CO2 injection experiment is carried out with two conceptual models, a homogeneous model and a heterogeneous model treated with multiple realization Monte Carlo simulations. Numerical simulator TOUGH2 with the equation of state module EOS7C is used for the simulations. Comparison of the model results with field data suggests that the pressure responses are captured with relatively good accuracy. Similarly, the model also provides an overall reasonable agreement and correct order of magnitude for predicted gas saturation values. However, as the heterogeneity pattern in the field data remains largely unknown, the model predictions can only be used to capture the mean behavior as well as to provide insights into how heterogeneity can influence the system behavior, by means of sensitivity analyses of the influence of heterogeneities on individual realizations.

  • 16.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Perroud, Herve
    Universit´e de Montpellier.
    Lofi, Johanna
    Universit´e de Montpellier.
    Denchik, Nataliya
    Universit´e de Montpellier.
    Lods, Gerard
    Universit´e de Montpellier.
    Pezard, Philippe
    Universit´e de Montpellier.
    Fagerlund, Fritjof
    Sharma, Prabhakar
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Modeling Gas Transport in the Shallow Subsurface in Maguelone Field Experiment2013In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, p. 337-345Article in journal (Refereed)
    Abstract [en]

    In this paper, TOUGH2/EOS7CA model is used to simulate the shallow injection-monitoring experiment carried outat Maguelone, France, during 2012 and 2013. The ultimate objective of the work is to improve our understanding ofgas transport in the shallow subsurface as well as to develop and validate the model to monitor it. This workrepresents first results towards modelling the nitrogen and CO2 injection experiments carried out. The pressure datafrom the first injection experiments in summer 2012 is used as basis for comparison. Work is presently going on toincorporate the experimental data into the numerical simulation further.

  • 17.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Sharma, Prabhakar
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Fagerlund, Fritjof
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Small scale laboratory design investigation of leakage of gaseous CO2 through heterogeneous subsurface system2012Conference paper (Refereed)
    Abstract [en]

    The technology for geological sequestration of carbon dioxide has been developed to reduce the CO2 emissions into the atmosphere from the use of fossil fuels in power generation and other industries. One of the main concerns associated with the geological storage is the possible leakage of CO2 into the shallow aquifers, for which effective detection methods are needed. The processes related to the spreading and trapping of CO2 in the reservoir formation and in supercritical conditions have received major attention and form the basis of understanding of CO2 trapping processes. Some of the CO2 may, however, also leak to the upper layers of the rock and all the way to land surface through faults and imperfections in the seal. A proper understanding and capability to detect such leaks is essential for a safe performance of any storage operation. This, in turn, involves a proper understanding of the processes related to the transport of gaseous CO2 in the nearsurface conditions, a topic that has received considerably less attention. The objective of this study is to analyze the transport and migration of gaseous CO2 in heterogeneous porous media, in controlled laboratory conditions. CO2 may reach the unsaturated zone by different leak mechanisms which may subsequently affect how and where it can be detected by leakage monitoring program. These mechanisms include exsolution from CO2 supersaturated water and continuous bubbling or gas flow along a leakage path. Below the water table, gaseous CO2 can also be trapped under capillary barriers. However, as more CO2 is supplied by leakage from below the water table, the pressure may at some point exceed the entry pressure of the barrier leading to a leak event. Similarly, fluctuations in the water table may also produce leak events of temporarily trapped CO2. In the unsaturated zone, the CO2 is heavier than air and may accumulate below ground surface and move laterally. The presence of heterogeneity influences both the movement and detectability of the CO2. Our laboratory experiment is designed and implemented for measuring CO2 distribution in time and space through the heterogeneous porous material. The CO2 concentrations through the domain are measured by using sensitive gas sensors. To better understand the consequences of CO2 leakage and how it can be detected, this study presents a conceptual model together with the design and setup of an experimental system to understand the transport, trapping and detectability of gaseous CO2 in a heterogeneous shallow geological system.

  • 18.
    Basirat, Farzad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Sharma, Prabhakar
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Niemi, Auli
    Uppsala University.
    Fagerlund, Fritjof
    Uppsala University.
    Small scale laboratory design investigation of leakage of gaseous CO2 through heterogeneous subsurface system2012Conference paper (Refereed)
    Abstract
  • 19.
    Berg, Sylvia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Burchardt, Steffi
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Deegan, Frances
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Riishuus, Morten S.
    Nordic Volcanological Center. Institute of Earth Sciences, University of Iceland, Sturlugata 7, 101 Reykjavik.
    Whitehouse, Martin J.
    Dept. of Geosciences, Swedish Museum of Natural History, SE-104 05, Stockholm, Sweden.
    Harris, Chris
    Dept. of Geological Sciences, University of Cape Town, Rondebosch, South Africa,.
    Freda, Carmela
    Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy.
    Ellis, Ben S.
    Inst. f. Geochemie und Petrologie, ETH, Clausiusstrasse 25, 8092, Zurich, Switzerland.
    Krumbholz, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Gústafsson, Ludvik E.
    Samband Islenskra Sveitarfélag, Borgartúni 30, pósthólf 8100, 128 Reykjavik, Iceland.
    Rapid high-silica magma generation in basalt-dominated rift settings2015Conference paper (Other academic)
  • 20.
    Berg, Sylvia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Burchardt, Steffi
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Riishuus, M.
    Krumbholz, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Gústafsson, L.E.
    Iceland's best kept secret2014In: Geology Today, ISSN 0266-6979, E-ISSN 1365-2451, Vol. 30, no 2, p. 54-60Article in journal (Refereed)
    Abstract [en]

    The ‘forgotten fjords’ and ‘deserted inlets’ of NE-Iceland, in the region between Borgarfjörður Eystri and Loðmundarfjörður, are not only prominent because of their pristine landscape, their alleged elfin settlements, and the puffins that breed in the harbour, but also for their magnificent geology. From a geological point of view, the area may hold Iceland's best kept geological secret. The greater Borgarfjörður Eystri area hosts mountain chains that consist of voluminous and colourful silicic rocks that are concentrated within a surprisingly small area (Fig. 1), and that represent the second-most voluminous occurrence of silicic rocks in the whole of Iceland. In particular, the presence of unusually large volumes of ignimbrite sheets documents extremely violent eruptions during the Neogene, which is atypical for this geotectonic setting. As a group of geoscientists from Uppsala University (Sweden) and the Nordic Volcanological Center (NordVulk, Iceland) we set out to explore this remote place, with the aim of collecting material that may allow us to unravel the petrogenesis of these large volumes of silicic rocks. This effort could provide an answer to a long-standing petrological dilemma; the question of how silicic continental crust is initially created. Here we document on our geological journey, our field strategy, and describe our field work in the remote valleys of NE-Iceland.

  • 21.
    Berg, Sylvia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Burchardt, Steffi
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Riishuus, M.S.
    Deegan, Frances
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Harris, C.
    Whitehouse, M.J.
    Gustafsson, L.E.
    Making Earth’s earliest continental crust: an analogue from voluminous Neogene silicic volcanism in NE-Iceland2014Conference paper (Refereed)
    Abstract [en]

    Borgarfjörður Eystri in NE-Iceland represents the second-most voluminous exposure of silicic eruptive rocksin Iceland and is a superb example of bimodal volcanism (Bunsen-Daly gap), which represents a long-standingcontroversy that touches on the problem of crustal growth in early Earth. The silicic rocks in NE-Iceland approach25 % of the exposed rock mass in the region (Gústafsson et al., 1989), thus they significantly exceed the usual≤ 12 % in Iceland as a whole (e.g. Walker, 1966; Jonasson, 2007). The origin, significance, and duration of thevoluminous (> 300 km3) and dominantly explosive silicic activity in Borgarfjörður Eystri is not yet constrained(c.f. Gústafsson, 1992), leaving us unclear as to what causes silicic volcanism in otherwise basaltic provinces.Here we report SIMS zircon U-Pb ages and δ18O values from the region, which record the commencement ofsilicic igneous activity with rhyolite lavas at 13.5 to 12.8 Ma, closely followed by large caldera-forming ignimbriteeruptions from the Breiðavik and Dyrfjöll central volcanoes (12.4 Ma). Silicic activity ended abruptly with dacitelava at 12.1 Ma, defining a ≤ 1 Myr long window of silicic volcanism. Magma δ18O values estimated fromzircon range from 3.1 to 5.5 (± 0.3; n = 170) and indicate up to 45 % assimilation of a low-δ18O component (e.g.typically δ18O = 0 h Bindeman et al., 2012). A Neogene rift relocation (Martin et al., 2011) or the birth of anoff-rift zone to the east of the mature rift associated with a thermal/chemical pulse in the Iceland plume (Óskarsson& Riishuus, 2013), likely brought mantle-derived magma into contact with fertile hydrothermally-altered basalticcrust. The resulting interaction triggered large-scale crustal melting and generated mixed-origin silicic melts. Suchrapid formation of silicic magmas from sustained basaltic volcanism may serve as an analogue for generatingcontinental crust in a subduction–free early Earth (e.g. ≥ 3 Ga, Kamber et al., 2005).

    REFERENCES:Bindeman, I.N., et al., 2012. Terra Nova 24, 227–232.Gústafsson, L.E., et al., 1989. Jökull, v. 39, 75–89.Gústafsson, L.E., 1992. PhD dissertation, Freie Universität Berlin.Jonasson, K., 2007. Journal of Geodynamics, 43, 101–117.Kamber, B.S., et al., 2005. Earth Planet. Sci. Lett., Vol. 240 (2), 276-290.Martin, E., et al., 2011. Earth Planet. Sc. Lett., 311, 28–38.Óskarsson, B.V., & Riishuus, M.S., 2013. J. Volcanol. Geoth.Res., 267, 92–118.Walker, G.P.L., 1966. Bull. Volcanol., 29 (1), 375-402.

  • 22.
    Berg Wiklund, Hannes
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Submarine slope instability as a cause of contaminated sediment dispersal in Ångermanälven, Sweden2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study aims at providing results for the analysis of the stratigraphy underlying contaminated sediments in Ångermanälven. The contaminated sediments, containing heavy metals and persistent organic pollutants, are derived from wastewater discharged into Ångermanälven from nearby paper and pulp industries. These sediments consist of cellulose fibres deposited as fibrebanks, or as fibre-rich sediments in the case where fibres are mixed with natural sediments. The importance of the underlying geology is enhanced since the contaminated sediments are deposited in an area where submarine landslides and slope movements occur frequently. In this study two sediment cores from a fibrebank in Ångermanälven are analysed. This is done in order to assess the risk of contaminants being dispersed in the ecosystem as a result of mass movements. Stratigraphic correlation with results from previous sediment core analysis in the middle of the estuary (International Ocean Discovery Program expedition #347) is achieved through magnetic susceptibility and density measurements of the sediment. Results show that silt layers and clay units situated throughout the estuary are potentially weak and geotechnical investigations are necessary to assess the risk of slope movements over these units. With further analysis of fibrebanks and the use of a vibro-corer, the contact between the fibrebanks and underlying sediment could be captured and further correlation establishing the stratigraphy of the estuary achieved.

  • 23. Bird, Anna
    et al.
    Stevens, Thomas
    Department of Geography, Royal Holloway University of London, UK.
    Rittner, Martin
    Vermeesch, Pieter
    Carter, Andrew
    Andò, Sergio
    Garzanti, Eduardo
    Lu, Huayu
    Nie, Junsheng
    Zeng, Lin
    Zhang, Hanzhi
    Xu, Zhiwei
    Quaternary dust source variation across the Chinese Loess Plateau2015In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 435, p. 254-264Article in journal (Refereed)
  • 24.
    Bishop, Kevin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Lyon, Steve
    Department of Physical Geography and Quaternary Geology Stockholm University, Stockholm, Sweden.
    Dahlke, Helen
    Department of Physical Geography and Quaternary Geology Stockholm University, Stockholm, Sweden.
    The Relationship Between Land Use and Water2012In: EOS: Transactions, ISSN 0096-3941, E-ISSN 2324-9250, Vol. 93, no 28, p. 259-Article in journal (Other academic)
    Abstract [en]

    The question posed in the title of this workshop formed its focus as an international group of more than 50 researchers and managers gathered to discuss our current level of understanding of land-water interactions and the potential impacts this has for resource management. Special emphasis was placed on the Ethiopian highlands, which deliver more than 85% of the flow in the Nile in Egypt. The 2-day workshop, held at the Swedish University of Agricultural Sciences in Uppsala, was cosponsored by the Swedish Ministry for Foreign Affairs as part of its special allocation for global food security and by the International Union of Forest Research Organizations' Unit 3.05, Forest Operations Ecology.

  • 25.
    Blythe, Lara
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Deegan, Frances
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Freda, C.
    Jolis, Ester Muños
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Masotta, M.
    Misiti, V.
    Taddeucci, J.
    Troll, V.R.
    Time-monitored vesiculation processes in magma-carbonate interaction experiments2014In: Contributions to Mineralogy and Petrology, ISSN 0010-7999, E-ISSN 1432-0967Article in journal (Other academic)
  • 26.
    Blythe, Lara
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Misiti, Valeria
    Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome.
    Masotta, Matteo
    Dipartimento di Scienze della Terra, Sapienza Università di Roma, Rome, Italy.
    Taddeucci, Jacopo
    Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome.
    Freda, Carmela
    Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Deegan, Frances
    Laboratory for Isotope Geology, Swedish Museum of Natural History, Stockhom, Sweden..
    Jolis, Ester
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Time-monitored vesiculation and dissolution during magma-carbonate interaction experiments: Merapi (Indonesia) and Vesuvius (Italy).Manuscript (preprint) (Other academic)
  • 27. Boles, Oliver
    et al.
    Courtney Mustaphi, Colin
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Archaeology and Ancient History, Archaeology. University of York.
    Richer, S
    Marchant, R
    Joining the dots of land-use and land-cover change in Eastern Africa2018In: PAGES News, ISSN 1811-1602, E-ISSN 1811-1610, Vol. 26, no 1, p. 16-17Article in journal (Refereed)
  • 28.
    Bordiga, Manuela
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Henderiks, Jorijntje
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Tori, F.
    Univ Florence, Dipartimento Sci Terra, I-50121 Florence, Italy..
    Monechi, S.
    Univ Florence, Dipartimento Sci Terra, I-50121 Florence, Italy..
    Fenero, R.
    Univ Zaragoza, Dept Ciencias Tierra, E-50009 Zaragoza, Spain.;Univ Zaragoza, Inst Univ Invest Ciencias Ambientales Aragon, E-50009 Zaragoza, Spain..
    Legarda-Lisarri, A.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Univ Zaragoza, Dept Ciencias Tierra, E-50009 Zaragoza, Spain.;Univ Zaragoza, Inst Univ Invest Ciencias Ambientales Aragon, E-50009 Zaragoza, Spain..
    Thomas, E.
    Yale Univ, Dept Geol & Geophys, New Haven, CT 06520 USA.;Wesleyan Univ, Dept Earth & Environm Sci, Middletown, CT 06459 USA..
    Microfossil evidence for trophic changes during the Eocene-Oligocene transition in the South Atlantic (ODP Site 1263, Walvis Ridge)2015In: Climate of the Past, ISSN 1814-9324, E-ISSN 1814-9332, Vol. 11, no 9, p. 1249-1270Article in journal (Refereed)
    Abstract [en]

    The biotic response of calcareous nannoplankton to environmental and climatic changes during the Eocene-Oligocene transition was investigated at a high resolution at Ocean Drilling Program (ODP) Site 1263 (Walvis Ridge, southeast Atlantic Ocean) and compared with a lower-resolution benthic foraminiferal record. During this time interval, global climate, which had been warm under high levels of atmospheric CO2 (pCO(2)) during the Eocene, transitioned into the cooler climate of the Oligocene, at overall lower pCO(2). At Site 1263, the absolute nannofossil abundance (coccoliths per gram of sediment; N g(-1)) and the mean coccolith size decreased distinctly after the E-O boundary (EOB; 33.89 Ma), mainly due to a sharp decline in abundance of large-sized Reticulofenestra and Dictyococcites, occurring within a time span of similar to 47 kyr. Carbonate dissolution did not vary much across the EOB; thus, the decrease in abundance and size of nannofossils may reflect an overall decrease in their export production, which could have led to variations in the food availability for benthic foraminifers. The benthic foraminiferal assemblage data are consistent with a global decline in abundance of rectilinear species with complex apertures in the latest Eocene (similar to 34.5 Ma), potentially reflecting changes in the food source, i.e., phytoplankton. This was followed by a transient increased abundance of species indicative of seasonal delivery of food to the sea floor (Epistominella spp.; similar to 33.9-33.4 Ma), with a short peak in overall food delivery at the EOB (buliminid taxa; similar to 33.8 Ma). Increased abundance of Nuttallides umbonifera (at similar to 33.3 Ma) indicates the presence of more corrosive bottom waters and possibly the combined arrival of less food at the sea floor after the second step of cooling (Step 2). The most important changes in the calcareous nannofossil and benthic communities occurred similar to 120 kyr after the EOB. There was no major change in nannofossil abundance or assemblage composition at Site 1263 after Step 2 although benthic foraminifera indicate more corrosive bottom waters during this time. During the onset of latest-Eocene-earliest-Oligocene climate change, marine phytoplankton thus showed high sensitivity to fast-changing conditions as well as to a possibly enhanced, pulsed nutrient supply and to the crossing of a climatic threshold (e.g., pCO(2) decline, high-latitude cooling and changes in ocean circulation).

  • 29. Bosi, Ferdinando
    et al.
    Skogby, Henrik
    Lazor, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Reznitskii, Leonid
    Atomic arrangements around the O3 site in Al- and Cr-rich oxytourmalines: a combined EMP, SREF, FTIR and Raman study2015In: Physics and chemistry of minerals, ISSN 0342-1791, E-ISSN 1432-2021, Vol. 42, no 6, p. 441-453Article in journal (Refereed)
  • 30.
    Botting, Joseph P.
    et al.
    Nanjing Inst Geol & Palaeontol, 39 East Beijing Rd, Nanjing 210008, Jiangsu, Peoples R China.;Natl Museum Wales, Dept Geol, Cathays Pk, Cardiff CF10 3LP, S Glam, Wales..
    Peel, John S.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Early Cambrian Sponges Of The Sirius Passet Biota, North Greenland2016In: PAPERS IN PALAEONTOLOGY, ISSN 2056-2799, Vol. 2, no 4, p. 463-487Article in journal (Refereed)
    Abstract [en]

    The Sirius Passet Biota of the Buen Formation in North Greenland is one of the key Burgess Shale-type faunas, as it represents the only diverse early Cambrian (Stage 2, Series 3) biota from Laurentia. The sponges are one of the major components of the fauna, although they appear to be much less abundant than arthropods, based on the available collections. At least 13 species are described here, including the new taxa Hamptonia limatula sp. nov., Lenica perversa sp. nov., Saetaspongia procera sp. nov., Constellatispongia canismajorii gen. et sp. nov. and Crassicoactum cucumis gen. et sp. nov. An additional new species, Ratcliffespongia freuchenensis sp. nov., is described from the upper part of the Buen Formation. The assemblage is dominated by a major lineage of protomonaxonids, together with rarer reticulosans and demosponges. Some taxa, such as the anthaspidellid lithistid Fieldospongia bellilineata, were previously known only from Laurentian faunas; others, such as Saetospongia densa, Solactiniella cf. plumata and Lenica unica, were previously recognized from South China and/or Siberia. The described assemblage confirms the cosmopolitan distribution of Cambrian sponges generally, and suggests that the differences between Laurentian and Chinese assemblages are due more to a taxonomic overturn during Cambrian Series 2, Stage 4, than to the geographical separation. Furthermore, crown-group demosponges appear to have occupied shallow-water (perhaps dominantly platform) environments at this time, and may have been much more diversified and widespread than is currently recognized during the early Cambrian.

  • 31.
    Brocks, J. J.
    et al.
    Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT, Australia..
    Jarrett, A. J. M.
    Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT, Australia.;Geosci Australia, GPO BOX 378, Canberra, ACT 2601, Australia..
    Sirantoine, E.
    Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT, Australia.;Ecole Normale Super Lyon, Dept Sci Terre, 46 Allee Italie, F-69007 Lyon, France..
    Kenig, F.
    Univ Illinois, Dept Earth & Environm Sci, Chicago, IL USA..
    Moczydlowska, Malgorzata
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Porter, S.
    Univ Calif Santa Barbara, Dept Earth Sci, Santa Barbara, CA 93106 USA..
    Hope, J.
    Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT, Australia..
    Early sponges and toxic protists: possible sources of cryostane, an age diagnostic biomarker antedating Sturtian Snowball Earth2016In: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 14, no 2, p. 129-149Article in journal (Refereed)
    Abstract [en]

    The period 800-717million years (Ma) ago, in the lead-up to the Sturtian Snowball glaciation, saw an increase in the diversity of eukaryotic microfossils. To afford an independent and complementary view of this evolutionary period, this study presents the distribution of eukaryotic biomarkers from three pre-Sturtian successions across the supercontinent Rodinia: the ca. 780Ma Kanpa Formation of the Western Australian Officer Basin, the ca. 800-740Ma Visingso Group of Sweden, and the 740Ma Chuar Group in Arizona, USA. The distribution of eukaryotic steranes is remarkably similar in the three successions but distinct from all other known younger and older sterane assemblages. Cholestane was the only conventional structure, while indigenous steranes alkylated in position C-24, such as ergostane, stigmastane, dinosterane and isopropylcholestane, and n-propylcholestane, were not observed. This sterane distribution appears to be age diagnostic for the pre-Sturtian Neoproterozoic. It attests to the distinct evolutionary state of pre-Snowball eukaryotes, pointing to a taxonomic disparity that was still lower than in the Ediacaran (635-541Ma). All three basins also show the presence of a new C-28 sterane that was tentatively identified as 26-methylcholestane, here named cryostane. The only known extant organisms that can methylate sterols in the 26-position are demosponges. This assignment is plausible as molecular clocks place the appearance of the earliest animals into the pre-Sturtian Neoproterozoic. The unusual 26-methylsterol may have protected sponges, but also other eukaryotes, against their own membranolytic toxins. Some protists release lytic toxins to deter predators and kill eukaryotic prey. As conventional membrane sterols can be the site of attack for these toxins, sterols with unusual side-chain modification protect the cell. This interpretation of cryostane supports fossil evidence of predation in the Chuar Group and promotes hypotheses about the proliferation of eukaryophagy in the lead-up to the Cryogenian.

  • 32.
    Budd, David A.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Dahren, Börje
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Burchardt, Steffi
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Persistent multitiered magma plumbing beneath Katla volcano, Iceland2016In: Geochemistry Geophysics Geosystems, ISSN 1525-2027, E-ISSN 1525-2027, Vol. 17, no 3, p. 966-980Article in journal (Refereed)
    Abstract [en]

    Recent seismic unrest and a persistent Holocene eruption record at Katla volcano, Iceland indicate that a near-future eruption is possible. Previous petrological investigations suggest that Katla is supplied by a simple plumbing system that delivers magma directly from depth, while seismic and geodetic data also point toward the existence of upper-crustal magma storage. To characterize Katla's recent plumbing system, we established mineral-melt equilibrium crystallization pressures from four age-constrained Katla tephras spanning from 8 kyr BP to 1918. The results point to persistent shallow- (≤8 km depth) as well as deep-crustal (ca. 10 – 25 km depth) magma storage beneath Katla throughout the last 8 kyr. The presence of multiple magma storage regions implies that mafic magma from the deeper reservoir system may become gas-rich during ascent and storage in the shallow crust and erupt explosively. Alternatively, it might intersect evolved magma pockets in the shallow-level storage region, and so increase the potential for explosive mixed-magma ash eruptions.

  • 33.
    Budd, David
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Dahrén, Börje
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Burchardt, Steffi
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Persistent shallow magma storage beneath Katla volcano2014Conference paper (Refereed)
  • 34.
    Budd, David
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Jolis, Ester Muños
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Deegan, Frances
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Toba super-eruption fuelled by catastrophic roof disintegration2014Conference paper (Refereed)
  • 35.
    Budd, Graham
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Early animal evolution and the origins of nervous systems2015In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 370, no 1684, article id 20150037Article in journal (Refereed)
    Abstract [en]

    Understanding the evolution of early nervous systems is hazardous because we lack good criteria for determining homology between the systems of distant taxa; the timing of the evolutionary events is contested, and thus the relevant ecological and geological settings for them are also unclear. Here I argue that no simple approach will resolve the first issue, but that it remains likely that animals evolved relatively late, and that their nervous systems thus arose during the late Ediacaran, in a context provided by the changing planktonic and benthic environments of the time. The early trace fossil provides the most concrete evidence for early behavioural diversification, but it cannot simply be translated into increasing nervous system complexity: behavioural complexity does not map on a one-to-one basis onto nervous system complexity, both because of possible limitations to behaviour caused by the environment and because we know that even organisms without nervous systems are capable of relatively complex behaviour.

  • 36.
    Budd, Graham
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Jackson, Illiam
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Ecological innovations in the Cambrian and the origins of the crown group phyla2016In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 371, no 1685Article in journal (Refereed)
    Abstract [en]

    Simulation studies of the early origins of the modern phyla in the fossil record, and the rapid diversification that led to them, show that these are inevitable outcomes of rapid and long-lasting radiations. Recent advances in Cambrian stratigraphy have revealed a more precise picture of the early bilaterian radiation taking place during the earliest Terreneuvian Series, although several ambiguities remain. The early period is dominated by various tubes and a moderately diverse trace fossil record, with the classical ‘Tommotian’ small shelly biota beginning to appear some millions of years after the base of the Cambrian at ca 541 Ma. The body fossil record of the earliest period contains a few representatives of known groups, but most of the record is of uncertain affinity. Early trace fossils can be assigned to ecdysozoans, but deuterostome and even spiralian trace and body fossils are less clearly represented. One way of explaining the relative lack of clear spiralian fossils until about 536 Ma is to assign the various lowest Cambrian tubes to various stem-group lophotrochozoans, with the implication that the groundplan of the lophotrochozoans included a U-shaped gut and a sessile habit. The implication of this view would be that the vagrant lifestyle of annelids, nemerteans and molluscs would be independently derived from such a sessile ancestor, with potentially important implications for the homology of their sensory and nervous systems.

  • 37.
    Budd, Graham
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Jensen, Sören
    Univ Extremadura, Fac Ciencias, Area Paleontol, Badajoz 06006, Spain.
    The origin of the animals and a ‘Savannah’ hypothesis for early bilaterian evolution2017In: Biological Reviews, ISSN 1464-7931, E-ISSN 1469-185X, Vol. 92, no 1, p. 446-473Article in journal (Refereed)
    Abstract [en]

    The earliest evolution of the animals remains a taxing biological problem, as all extant clades are highly derived and the fossil record is not usually considered to be helpful. The rise of the bilaterian animals recorded in the fossil record, commonly known as the ‘Cambrian explosion’, is one of the most significant moments in evolutionary history, and was an event that transformed first marine and then terrestrial environments. We review the phylogeny of early animals and other opisthokonts, and the affinities of the earliest large complex fossils, the so-called ‘Ediacaran’ taxa. We conclude, based on a variety of lines of evidence, that their affinities most likely lie in various stem groups to large metazoan groupings; a new grouping, the Apoikozoa, is erected to encompass Metazoa and Choanoflagellata. The earliest reasonable fossil evidence for total-group bilaterians comes from undisputed complex trace fossils that are younger than about 560 Ma, and these diversify greatly as the Ediacaran–Cambrian boundary is crossed a few million years later. It is generally considered that as the bilaterians diversified after this time, their burrowing behaviour destroyed the cyanobacterial mat-dominated substrates that the enigmatic Ediacaran taxa were associated with, the so-called ‘Cambrian substrate revolution’, leading to the loss of almost all Ediacara-aspect diversity in the Cambrian. Why, though, did the energetically expensive and functionally complex burrowing mode of life so typical of later bilaterians arise? Here we propose a much more positive relationship between late-Ediacaran ecologies and the rise of the bilaterians, with the largely static Ediacaran taxa acting as points of concentration of organic matter both above and below the sediment surface. The breaking of the uniformity of organic carbon availability would have signalled a decisive shift away from the essentially static and monotonous earlier Ediacaran world into the dynamic and burrowing world of the Cambrian. The Ediacaran biota thus played an enabling role in bilaterian evolution similar to that proposed for the Savannah environment for human evolution and bipedality. Rather than being obliterated by the rise of the bilaterians, the subtle remnants of Ediacara-style taxa within the Cambrian suggest that they remained significant components of Phanerozoic communities, even though at some point their enabling role for bilaterian evolution was presumably taken over by bilaterians or other metazoans. Bilaterian evolution was thus an essentially benthic event that only later impacted the planktonic environment and the style of organic export to the sea floor.

  • 38. Buylaert, Jan-Pieter
    et al.
    Yeo, Eun-Young
    Thiel, Christine
    Yi, Shuangwen
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Thompson, Warren
    Frechen, Manfred
    Murray, Andrew
    Lu, Huayu
    A detailed post-IR IRSL chronology for the last interglacial soil at the Jingbian loess site (northern China)2015In: Quaternary Geochronology, ISSN 1871-1014, E-ISSN 1878-0350, Vol. 30, p. 194-199Article in journal (Refereed)
    Abstract [en]

    The chronology of dust deposition and climate during the last interglacial is poorly known on the Chinese Loess Plateau. Here, 51 samples were taken from the similar to 5 m S1 palaeosol (MIS5) at the desert marginal Jingbian site to develop what is currently the most detailed S1 chronology on the Plateau using instrumental dating techniques. We use the post-IR IRSL signal from sand-sized grains of K-rich feldspar. Signal resetting in the agricultural layer shows that it is possible to almost completely zero this signal in nature. First IR stimulation plateau measurements show that there is no clear dependence of D-e on first IR stimulation temperature between 50 and 260 degrees C suggesting negligible signal fading. Resultant ages are consistent with a last interglacial age (similar to 130 to similar to 75 ka) and are also consistent within errors with continuous linear sedimentation rates. The average mass accumulation rate for S1 is similar to 150 g m(-2) a(-1), considerably higher than at many other sites but within the overall range of Loess Plateau estimates. The remarkably stable sediment accumulation at the site contrasts with a more complex record of environmental and monsoonal change recorded in grain-size and magnetic susceptibility.

  • 39.
    Carracedo, Juan Carlos
    et al.
    Estación Volcanológica de Canarias, IPNA-Consejo Superior de Investigaciones Científicas (CSIC), La Laguna, 38206, Tenerife, Spain.
    Pérez-Torrado, Francisco José
    Departamento de Física-Geología, Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Spain.
    Rodríguez González, Alejandro
    Grupo de Investigación GEOVOL, Dpto. de Física, Universidad de Las Palmas de Gran Canaria, Spain .
    Soler, Vicente
    Estación Volcanológica de Canarias, IPNA‐CSIC, La Laguna, Tenerife, Spain.
    Fernández Turiel, José Luis
    Instituto de Ciencias de la Tierra Jaume Almera, CSIC, Barcelona, Spain.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Wiesmaier, Sebastian
    Department of Earth and Environmental Sciences, Ludwig-Maximilians Universität (LMU), Munich, Germany.
    The 2011 submarine volcanic eruption in El Hierro (Canary Islands)2012In: Geology Today, ISSN 0266-6979, E-ISSN 1365-2451, Vol. 28, no 2, p. 53-58Article in journal (Other (popular science, discussion, etc.))
    Abstract [en]

    Forty years after the Teneguía Volcano (La Palma, 1971), a submarine eruption took place off the town of La Restinga, south of El Hierro, the smallest and youngest island of the Canarian Archipelago. Precursors allowed an early detection of the event and its approximate location, suggesting it was submarine. Uncertainties derived from insufficient scientific information available to the authorities during the eruption, leading to disproportionate civil protection measures, which had an impact on the island's economy—based primarily on tourism—while residents experienced extra fear and distress.

  • 40.
    Carracedo, Juan Carlos
    et al.
    Estación Volcanológica de Canarias, IPNA-Consejo Superior de Investigaciones Científicas (CSIC), La Laguna, 38206, Tenerife, Spain.
    Rodriguez-Gonzalez, Alejandro
    Pérez-Torrado, Francisco José
    Departamento de Física-Geología, Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Spain.
    Fernandez-Turiel, J-L.
    Institute of Earth Sciences Jaume Almera, ICTJA-CSIC, Barcelona, Spain.
    Paris, Raphaël
    Université Blaise Pascal, UMR 6524, Clermont-Ferrand & CNRS, France.
    Rodríguez-Badiola, E.
    Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain.
    Pestana-Pérez, G.
    Consejería de Agricultura, Ganadería, Pesca y Alimentación, Gobierno de Canarias, Spain.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Wiesmaier, Sebastian
    Departamento de Física (GEOVOL), Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Canary, Islands, Spain.
    Geological Hazards in the Teide Volcanic Complex2013In: Teide Volcano: Geology and Eruptions of a Highly Differentiated Oceanic Stratovolcano, Springer Berlin/Heidelberg, 2013, p. 249-272Chapter in book (Refereed)
    Abstract [en]

    The island of Tenerife displays contrasted densities of population, from the densely occupied coastal zones (including tourist resorts, airport, energy facilities, etc.) to the sparsely populated forests and mountainous highlands, where most of the recent volcanic events are located. Considering the low frequency of historical eruptions (compared to Hawaii or Reunion Island for example), the assessment of geological hazards must also rely on the analysis and interpretation of prehistorical events, going back to at least the Late Quaternary. In this chapter, we review the hazards related to Teide’s volcanism, but also those from increased seismicity and from slope instability. We discuss the origin of low magnitude earthquakes, and particularly the 2004 episode of unrest. New estimates on cumulative volumes for resurfacing by lava flows during the last few thousand years are provided to serve as a tool for building a lava flow hazard map of Tenerife. Hazards related to explosive activity are also considered and although possible, with phreatomagmatic eruptions being the most likely style anticipated, explosive events are of relatively low probability at Teide in the near future.

  • 41.
    Carracedo, Juan Carlos
    et al.
    Estación Volcanológica de Canarias, IPNA-Consejo Superior de Investigaciones Científicas (CSIC), La Laguna, 38206, Tenerife, Spain.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    From Myth to Science: The Contribution of Mount Teide to the Advancement of Volcanology2013In: Teide Volcano: Geology and eruptions of a highly differentiated oceanic stratovolcano, Springer Berlin/Heidelberg, 2013, p. 1-21Chapter in book (Refereed)
    Abstract [en]

    This chapter outlines the progress of geological research into the origin and evolution of the Teide Volcanic Complex within the framework of Tenerife Island, the Canary Islands, and oceanic volcanism in general. Initially considered to relate to either the entrance to ‘Hell’ or to mythical Atlantis, for von Buch, von Humboldt, Lyell and the other great eighteenth and nineteenth century naturalists Teide eventually helped to shape a new, and at that time revolutionary concept; the origin of volcanic rocks from solidified magma. This school of thought slowly cast aside Neptunism and removed some of the last barriers for the development of modern Geology and Volcanology as the sciences we know today. Despite the volcanic nature of the Canaries having been already recognised by the twentieth century, modern geological understanding of the archipelago progressed most significantly with the advent of plate tectonics. While some authors still maintain a link between the Canaries and the Atlas tectonic regime (see also Chap.​ 2), geological research truly advanced in the Canaries through comparison with hotspot-derived archipelagos, particularly the Hawaiian Islands. This approach, initiated in the 1970s, provided a breakthrough in the understanding of Canary volcanism, demonstrating Tenerife and Teide to be one of the world’s most interesting, complex and to many, one of the most iconic of oceanic volcanoes.

  • 42.
    Carracedo, Juan Carlos
    et al.
    Estación Volcanológica de Canarias, IPNA-Consejo Superior de Investigaciones Científicas (CSIC), La Laguna, 38206, Tenerife, Spain.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Solid Earth Geology.
    Structural and Geological Elements of Teide Volcanic Complex: Rift Zones and Gravitational Collapses2013In: Teide Volcano: Geology and eruptions of a highly differentiated oceanic stratovolcano, Springer, 2013, p. 57-74Chapter in book (Refereed)
    Abstract [en]

    Initially recognised in the Hawaiian Islands, volcanic rift zones and associated giant landslides have been extensively studied in the Canaries, where several of their more significant structural and genetic elements have been established. Almost 3,000 km of water tunnels (galerías) that exist in the western Canaries provide a unique possibility to access the deep structure of the island edifices. Recent work shows that rift zones to control the construction of the islands, possibly from the initial stages of island development, form the main relief features (shape and topography), and concentrate eruptive activity, making them crucial elements in defining the distribution of volcanic hazards on ocean islands.

  • 43.
    Carracedo, Juan Carlos
    et al.
    Estación Volcanológica de Canarias, IPNA-Consejo Superior de Investigaciones Científicas (CSIC), La Laguna, 38206, Tenerife, Spain.
    Troll, ValentinUppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Teide Volcano: Geology and Eruptions of a Highly Differentiated Oceanic Stratovolcano2013Collection (editor) (Other academic)
    Abstract [en]

    Teide Volcano has many different meanings: For the Guanche aborigines, who endured several of its eruptions, it was Echeide (Hell). Early navigators had in Teide, a lifesaving widely visible landmark that was towering over the clouds. For the first explorers, Teide was a challenging and dangerous climb, since it was thought that Teide's peak was so high that from its summit the sun was too close and far too hot to survive. Teide was considered the highest mountain in the world at that time and measuring its height precisely was a great undertaking and at the time of global scientific significance. For von Buch, von Humboldt, Lyell and other great 18th and19th century naturalists, Teide helped to shape a new and now increasingly 'volcanic' picture, where the origin of volcanic rocks (from solidified magma) slowly casted aside Neptunism and removed some of the last barriers for the development of modern Geology and Volcanology as the sciences we know today. For the present day population of Tenerife, living on top of the world's third tallest volcanic structure on the planet, Teide has actually become "Padre Teide", a fatherly protector and an emblematic icon of Tenerife, not to say of the Canaries as a whole. The UNESCO acknowledged this iconic and complex volcano, as "of global importance in providing evidence of the geological processes that underpin the evolution of oceanic islands". Today, 'Teide National Park' boasts 4 Million annual visitors including many 'volcano spotters' and is a spectacular natural environment which most keep as an impression to treasure and to never forget. For us, the editors of this book, Teide is all of the above; a 'hell of a job', a navigation point on cloudy days, a challenge beyond imagination, a breakthrough in our understanding of oceanic volcanism that has shaped our way of thinking about volcanoes, and lastly, Teide provides us with a reference point from where to start exploring other oceanic volcanoes in the Canaries and beyond. Here we have compiled the different aspects and the current understanding of this natural wonder.

  • 44.
    Carracedo, Juan Carlos
    et al.
    Estación Volcanológica de Canarias, IPNA-Consejo Superior de Investigaciones Científicas (CSIC), La Laguna, 38206, Tenerife, Spain.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    The Geology of the Canary Islands2016Book (Other academic)
  • 45.
    Carracedo, Juan Carlos
    et al.
    Estación Volcanológica de Canarias, IPNA-Consejo Superior de Investigaciones Científicas (CSIC), La Laguna, 38206, Tenerife, Spain.
    Troll, Valentin
    Department of Geology, Trinity College, Dublin.
    Pérez-Torrado, Francisco José
    Departamento de Física-Geología, Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Spain.
    Hansen, Alex
    Departamento Geología, Universidad de Las Palmas de Gran Canaria, Spain.
    Rodriguez-Badiola, Eduardo
    Museo Nacional de Ciencias Naturales, CSIC, Madrid.
    Paris, Raphael
    Maison de la Recherche, CNRS, Clermont-Ferrand, France.
    Guillou, Hervé
    Laboratoire des Sciences du Climat et de l'Environnement, CNRS, Gif-sur-Yvette, France.
    Scaillet, Stéphane
    Laboratoire des Sciences du Climat et de l'Environnement, CNRS, Gif-sur-Yvette, France.
    Reply to Comment on “Recent unrest at Canary Islands' Teide Volcano?”2007In: EOS: Transactions, ISSN 0096-3941, E-ISSN 2324-9250, Vol. 88, no 46, p. 488-Article in journal (Other academic)
    Abstract [en]

    Small-magnitude seismic episodes unrelated to a volcanic eruption have been a relatively frequent feature in all the Canaries without causing any significant public alarm. Conversely, great alarm was raised in May 2004 in Tenerife, when apparently numerous low-magnitude seismic signals were recorded, although only a few of them were actually felt in nearby villages.

    Public alarm was raised by (1) the publication on a Web site of imperceptible seismic signals as low as 0.6 on the Richter scale, most of which were not even adequately localized and yet were reproduced almost daily in the local and national press without further comment or explanation; (2) a Spanish national scientific committee being replaced by a local committee that was scientifically advised by a private company; and (3) publicity given by the media to the prediction made by members of the local committee of a potentially large scale explosive eruption in October 2004 (dubbed “the October volcano” by residents). Interestingly, obvious fumarole activity was absent in autumn 2004 during an inspection of Teide summit by three of us.

  • 46.
    Carracedo, Juan-Carlos
    et al.
    University of Las Palmas de Gran Canaria, Dept. of Physics, Las Palmas de Gran Canaria, Spain.
    Perez-Torrado, Francisco J.
    University of Las Palmas de Gran Canaria, Dept. of Physics, Las Palmas de Gran Canaria, Spain.
    Rodriguez-Gonzalez, Alejandro
    University of Las Palmas de Gran Canaria, Dept. of Physics, Las Palmas de Gran Canaria, Spain.
    Paris, Raphael
    Université Blaise Pascal Clermont-Ferrand II, France.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Barker, Abigail
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Volcanic and structural evolution of Pico do Fogo, Cape Verde2015In: Geology Today, ISSN 0266-6979, E-ISSN 1365-2451, Vol. 31, no 4, p. 146-152Article in journal (Refereed)
    Abstract [en]

    In recent months the media have drawn attention to the Cape Verde archipelago, with particular focus on the island of Fogo, the only island presently active and with an eruption that began on 23 November 2014, finally ceasing on 7 February 2015. The Monte Amarelo conical shield forms most of the 476 km2 almost circular island of Fogo. After attaining a critical elevation of about 3500 m, the Monte Amarelo shield volcano was decapitated by a giant landslide that formed a caldera-like depression (Cha das Caldeiras), which was subsequently partially filled by basaltic nested volcanism. This younger eruptive activity culminated in the construction of the 2829 m-high Pico do Fogo stratocone, apparently entirely made of layers of basaltic lapilli. Continued growth of the Pico do Fogo summit eruptions was interrupted in 1750, most likely after the stratocone reached a critical height. Since then, at least eight eruptions have taken place inside the landslide depression at the periphery of the Pico do Fogo cone, including the 2014–2015 eruptive event. Strong geological similarities with the Canary Islands, 1400 km to the north, have been frequently noted, probably as a consequence of a common process of origin and evolution associated with a mantle hot-spot. These similarities are particularly evident when comparing Fogo with the Teide Volcanic Complex on Tenerife, where a lateral collapse of the Las Cañadas stratovolcano also formed a large depression (the Caldera de Las Cañadas), now partially filled with the 3718 m-high Teide stratocone. However, important geological differences also exist and probably relate to the contrasting evolutionary stages of both islands. The Las Cañadas volcano on Tenerife formed at a late post-erosional stage, with predominantly evolved (trachyte and phonolite) magmas, while at Fogo basaltic volcanism is still dominant.

  • 47.
    Cheng, Gong
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Lötstedt, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Parameter sensitivity analysis of dynamic ice sheet models2019In: Computing Research Repository, no 1906.08197Article in journal (Other academic)
  • 48.
    Cheng, Gong
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Lötstedt, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Parameter sensitivity analysis of dynamic ice sheet models: Numerical computations2019In: The Cryosphere Discussions, ISSN 1994-0432, E-ISSN 1994-0440Article in journal (Other academic)
  • 49.
    Cheng, Gong
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Lötstedt, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    von Sydow, Lina
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    A full Stokes subgrid model for simulation of grounding line migration in ice sheets2019In: Computing Research Repository, no 1908.10751Article in journal (Other academic)
  • 50.
    Chew, David M.
    et al.
    Department of Geology, Trinity College Dublin, Dublin 2, Ireland .
    Ganerød, Morgan
    Geological Survey of Norway (NGU), Norway.
    Troll, Valentin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Mineralogy Petrology and Tectonics.
    Corfu, Fernando
    Department of Geosciences, Un iversity of Oslo, Norway.
    Meade, Fiona
    Department of Geology, Trinity College Dublin, Ireland.
    U-Pb TIMS zircon age constraints on the Tardree Rhyolite zircon fission track standard2008In: On Track Forum, Vol. 16, no 1Article in journal (Other academic)
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