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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.

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  • 4.
    Agard, Shenelle
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    In-Situ Gold Resource Estimation Using Satellite Remote Sensing and Machine Learning in Defunct Tailing Storage Facilities (South Africa)2023Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    The mining industry generates billions of tonnes of waste annually, which is often stored in tailings storage facilities (TSF). This waste is generated from the extraction of ore from surface or underground mines, as well as from metallurgical processing and low-grade stockpiles. TSF can have significant environmental impacts, as they can cause acid mine drainage resulting in the leaching and transport of heavy metals into ground and surface waters. With increasing demand for critical raw material, recent studies have shown that the valorisation of mine waste can be a potential secondary source of critical raw materials. The valorisation of mine waste is possible when the waste is accurately characterised.A novel method that uses multispectral satellite remote sensing and machine learning to estimate the mineral resource in a defunct TSF in the Witwatersrand Basin, South Africa is proposed in this research. Four machine learning models: 1) random forest (RF); 2) adaptive boosting (AB); 3) extra trees (ET); and 4) k-nearest neighbours are developed using supervised machine learning. The models are trained using training data acquired from a TSF with known gold concentration located 3 kilometres from the TSF and deployed on the TSF to predict the gold grades. The results of the machine learning model predictions indicates that machine learning models had high performances for predicting gold grades in the TSF. The AB, RF and ET, models performed best. Their performances were evaluated using the coefficient of determination (R2) value. The R2 values for the machine learning models were 0.95, 0.92, 0.87 and 0.70 for AB, ET, RF and kNN respectively. The mean gold grade predicted was 0.44 g/t by all machine learning models. This was compared to a 2D surficial geostatistical model which estimated 0.35g/t gold in the TSF using ordinary kriging and a 2D vertically averaged geostatistical model with an estimated 0.4 g/t mean gold grade. The short-wave infrared (SWIR) - band 11 at a 20 m spatial resolution had the highest correlation with the reflectance of gold in the TSF. This study demonstrated the value of leveraging multi-spectral remote sensing data and machine learning to perform mineral resource estimation in defunct TSF.

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  • 5.
    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.

  • 6. 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).

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  • 7.
    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)
  • 8.
    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.

  • 9.
    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. 

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  • 10.
    Andersson, Colin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Hoset, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Kusterosion på sydvästra Gotland: En undersökning i GIS och berggrundsgeologi2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Southwestern Gotland has a relatively diverse bedrock where both sandstone, limestone and marl areexposed. The purpose of the survey has been to investigate differences in coastal erosion regarding thecontent of the bedrock. This was done by taking samples from 9 different locations which were laterexamined in point load tests and a slake durability test. A GIS-analysis was also done where the coastalarea in old aerial images and modern orthophotos were compared. The results showed that the sandstoneand marl samples were approximately equally prone to break and that limestone was less prone. Theslake durability test showed that sandstone from one site had the least resistance to abrasion, sandstonefrom the marl areas had greater resistance and that the limestone area had marginally greater resistancethan the marl areas. The GIS analysis indicated that the sandstone and marl areas had a relatively highsensitivity to coastal erosion and that the limestone area was not particularly exposed to coastal erosion.

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  • 11.
    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.

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  • 12.
    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.

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  • 13.
    Apler, Anna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development. Geological Survey of Sweden.
    Kuchler, Magdalena
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development.
    Zillén, Lovisa
    Division of Marine Environment, Geological Survey of Sweden (SGU).
    Snowball, Ian
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development.
    The Anthropocene in the northern Baltic Sea – the case of contaminated fiberbanks and implications for sustainable developmentManuscript (preprint) (Other academic)
    Abstract [en]

    The epoch of humankind, the Anthropocene, is usually characterized by the global gaze, which places its focus on global environmental phenomena i.e. global warming and ocean acidification. In this article we argue that the Anthropocene could be better understood with a cross-scalar perspective and present the case of anthropogenic contaminated “fiberbanks” as an example. We present a geological example of the Anthropocene in a Swedish river estuary in the northern Baltic Sea, which hosted nine P&P mills along its’ shores and received large amounts of metal containing wastewater during the 20th century. As a result of the great acceleration and an increased national and global demand for pulp and paper products these fiberbanks formed in shallow waters. As artificial seabed features these thick deposits of contaminated organic-rich material negatively affect the adjacent aquatic environment. By constructing a chemostratigraphy based on sediment cores from accumulation areas and a metal pollution index we show how the aquatic system has recovered from metal pollution. We note, however, that the established stratigraphy fails to identify the fiberbanks, which remain in the shallow zones and are contaminant hotspots. In Sweden, there is an insufficient knowledge of contaminated sediments for a sustainable water and marine management. This knowledge gap in combination with human induced climate changes that may chemically and physically affect sediments and thus, alter dispersion of imbedded pollutants, results in poor understanding and long-term perception of the risks of contaminant dispersion from fiberbanks. We claim that these gaps of knowledge must be filled in order to reach an effective conservation at the same time as a sustainable blue growth in the northern Baltic Sea.

  • 14.
    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.

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  • 15.
    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.

  • 16.
    Ask, Maria
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Kukkonen, Ilmo
    University of Helsinki.
    Olesen, Odleiv
    Geological Survey of Norway.
    Lund, Björn
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Fagereng, Åke
    Cardiff University.
    Rutqvist, Jonny
    Lawrence Berkeley National Laboratory.
    Rosberg, Jan-Erik
    Lund University.
    Lorenz, Henning
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Proposed Drilling into Postglacial Faults: The Pärvie Fault System2021In: Glacially-Triggered Faulting / [ed] Holger Steffen, Odleiv Olesen, Raimo Sutinen, Cambridge: Cambridge University Press , 2021, p. 151-174Chapter in book (Refereed)
    Abstract [en]

    Postglacial faults in northern Fennoscandia have been investigated through geophysical methods, trenching, and mapping of brittle deformation structures. Very little is known about postglacial faults through direct measurements. A few short, up to 500 m deep, boreholes exist. Plans for a scientific drilling program were initiated in 2010. The drilling target has been identified: The Pärvie Fault system is the longest known postglacial fault in the world and has been proposed to have hosted an M8 earthquake near the end or just after the last glaciation. Further, this fault system is still microseismically active. The drill sites are north of the Arctic Circle, in a sparsely populated area. Existing site survey data, established logistics, and societal relevance through the fault’s proximity to mining and energy operations make this fault system an appropriate target. The International Continental Scientific Drilling Program approved a full drilling proposal in October 2019. This chapter presents an abbreviated version of the approved proposal.

  • 17.
    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.

  • 18.
    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.

  • 19.
    Barnes, Ethan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Assessment of Drone-Borne Multispectral Mapping in the Exploration of Magmatic Ni-Cu Sulphides – an Example from Disko Island, West Greenland2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The senseFly eBeePlus fixed-wing drone is a market available UAV compatible with a range of sensors that includes the Parrot Sequoia+ multispectral camera. Commercial applications of the drone predominantly focus on agriculture, environmental management, and engineering applications. The Sequoia 4-band multispectral sensor with bands optimised for plant health analysis, has a spectral range that coincides with the absorption features of iron. Previous studies with the use of hyperspectral sensors on multicopter UAVs have proven successful in the detection and delineation of hydroxides and sulphates associated with weathering of sulphides at the surface.

    This study aims to evaluate the ability of the eBeePlus drone equipped with a Parrot Sequoia+ sensor to effectively detect and delineate surficial sulphide mineral expressions by testing its capability on a known nickel-copper mineralisation occurrence at Illukunnguaq, on the north-western coast of Disko Island, West Greenland. Formally hosting a 28-tonne nickeliferous pyrrhotite massive sulphide boulder, many companies have sought this region for a possible extension of the mineralisation or another local mineral occurrence. Iron-feature band ratios and Spectral Angle Mapping (SAM) are two methods tested to first characterise the known occurrence, then search the wider region for other features with a similar signature as the Illukunnguaq dyke. To assist the evaluation and fine tune the Sequoia sensor, it will be compared against the trialled and trusted Rikola hyperspectral sensor, proven to map iron features. In addition, eigen maxima as one of many geomorphological indices that utilise the co-product Digital Surface Model (DSM) of the spectral survey, is employed to assess whether the Illukunnguaq dyke and other features are structurally mappable. 

    Results show that the Sequoia multispectral sensor, albeit less spectrally resolved than the Rikola hyperspectral sensor was able to detect surficial sulphide mineral expressions both by applying iron-feature band ratios and SAM. The latter was performed using laboratory measured and open-access library spectra. To fine-tune the tools compatible with the Sequoia sensor, in-depth investigations into iron-feature band ratio index values and best-fit library spectra for SAM was conducted. Confidence was increased by the blind detection of another known exposure and permitted a regional search to find additional features with spectral similarities to the Illukunnguaq dyke for future ground truthing. This study demonstrates that the eBeePlus drone can be used for mineral exploration when iron-sulphides are a part of the mineral system and outcropping at the surface. Leading field programs with detailed multispectral mapping can improve the efficiency of geologists by generating or verifying targets prior to ‘boots-on-the-ground’ geological sampling or mapping.

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  • 20.
    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.

  • 21.
    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, 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.

  • 22.
    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.

  • 23.
    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
  • 24.
    Baykal, Yunus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bateman, Mark D.
    Pfaff, Katharina
    Sechi, Daniele
    Banak, Adriano
    Šuica, Sanja
    Zhang, Haobo
    Nie, Junsheng
    Eurasian Ice Sheet derived meltwater pulses and their role in driving atmospheric dust activity: Late Quaternary loess sources in SE England2022In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 296, p. 107804-107804, article id 107804Article in journal (Refereed)
    Abstract [en]

    The role of Quaternary ice sheet fluctuations in driving meltwater pulses and ocean circulation perturbations is widely acknowledged. What is less clear is the role of these processes in driving changes in past atmospheric dust activity, and possible wider links between dust and climate. Terrestrial windblown dust (loess) deposits along the northern fringe of the European loess belt potentially record past atmospheric dust emission from regions close to the former Eurasian Ice Sheet (EIS) and provide a means to evaluate the role of ice sheet fluctuations in the past dust cycle. Numerical loess chronologies across this region generally agree on greatly enhanced dust deposition rates during MIS 2, when the EIS reached its maximum extent. Yet, uncertainties over the sources of this material prevent understanding of the precise causes of this greatly enhanced atmospheric dustiness, and any potential link to ice sheet fluctuations and climate. In southeast England, loess accumulation dominantly occurred in two phases centered on 25–23.5 ka and 20–19 ka, matching the timing of coalescence of the Fennoscandian and British-Irish ice sheets and specifically advances and retreats of nearby ice lobes in the western North Sea. As such, these deposits provide an ideal test of the role of ice sheet fluctuations in atmospheric dust dynamics. Here we undertake such a test through a detailed provenance study of loess in southeast England and potential dust source sediments across the North Sea region. We group extensive new and published data sets of detrital zircon U–Pb ages from basement rocks and Cenozoic sediments in the North Sea area, which not only provide new insight into both loess source, but also the nature of sediment transport over NW Europe into the North Sea basin more widely. Multi-proxy evidence allows us to unambiguously identify ice sheet derived sediments in the exposed North Sea basin as the dominant source of loess in southeast England, while fluvial sediments delivered by rivers draining Continental Europe possibly contributed additional source material to the first loess accumulation phase. We propose that sudden retreats of the North Sea Lobe released substantial amounts of sediment rich meltwater into the southern North Sea and Channel basins, driving accelerated dust emission, loess deposition and provenance variability in NW Europe during MIS 2. Moreover, we propose that this model of dust activity driven by proglacial sediment availability may be applicable for EIS marginal regions more widely, even where resultant loess cover is rarely preserved due to extensive erosion and reworking along the ice marginal spillway. This implies the role of ice sheets in controlling wider dust emission may be underestimated. In addition to driving changes in ocean circulation through meltwater pulses, ice sheet dynamics in the Quaternary may have also driven substantial and abrupt changes in atmospheric dust activity. This mechanism may in part explain the coupling between dust and climate events widely seen in Quaternary dust sediment records and suggests a possible major role of high latitude dust emission in MIS 2 dustiness across Europe and beyond.

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  • 25.
    Baykal, Yunus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Engström-Johansson, Alexandra
    Skurzyński, Jacek
    Zhang, Hanzhi
    He, Jing
    Lu, Huayu
    Adamiec, Grzegorz
    Költringer, Chiara
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Jary, Zdzisław
    Detrital zircon U–Pb age analysis of last glacial loess sources and proglacial sediment dynamics in the Northern European Plain2021In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 274, article id 107265Article in journal (Refereed)
    Abstract [en]

    Loess deposits along the northern fringe of the European loess belt potentially record past changes in dust emission from areas proximal to former ice sheets. Recent chronologies from loess deposits across this region generally agree on greatly enhanced dust deposition rates when the Fennoscandian Ice Sheet reached its maximum extent during the late last glacial. However, uncertainties over the material's source and origin limit understanding of the causes of this enhanced dust activity. In particular, loess in southwestern Poland has been attributed to multiple origins, mainly involving glaciofluvial outwash plains along the Fennoscandian Ice Sheet margin and/or local sources in the mountainous areas of the Sudetes and Western Carpathians. Here we apply detrital zircon U–Pb age analyses for a large number of grains recovered from four loess samples taken from different stratigraphic units exposed at Biały Kościół in southwestern Poland, previously luminescence dated to MIS 4–2, to assess loess provenance as well as its temporal evolution during last glacial Fennoscandian Ice Sheet fluctuations. Furthermore, we analysed the detrital zircon U–Pb age spectra of five samples from potential source sediments to constrain the history of sediment recycling and mixing within the Northern European Plain prior to deflation and loess deposition. The broad range of zircon age components detected in the four loess samples suggests both Fennoscandian and closer Peri-Gondwanan proto-sources while a narrow, dominant Carboniferous age peak is consistent with sourcing from the local Strzelin Hills in the Sudetic foreland. However, the presence of both Fennoscandian and Peri-Gondwanan derived grains in samples from potential source sediments reveals that this mixture of sediment sources is widespread across the Northern European Plain, as a result of long-term glacial and fluvial reworking of cover sediments in the proglacial area throughout the Quaternary. Local rivers draining the Sudetic foreland transported this Fennoscandian-Peri-Gondwanan sediment mixture along with particles denuded from the Strzelin Hills, resulting in a nearby, temporally stable dust source for the Biały Kościół loess during MIS 4–2, while dust emission rates were substantially increased during the last glacial maximum. Given that our model for loess formation at Biały Kościół essentially involves sediment distribution via rivers prior to short distance aeolian transport, we infer that the proportion of northern ice sheet derived particles in European loess deposits is mainly controlled by the drainage pattern of major rivers in relation to Pleistocene ice margins where glaciofluvial sediment is abundant. Based on the presence of Fennoscandian derived zircon grains in European loess deposits, we constrain a southern limit of the influence of northern ice sheet dust sources along the central European highlands that currently divide drainage between the Northern European Plain and the Danube Basins.

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  • 26.
    Bazargan, Mohsen
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Hobe, Alex
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Geophysics.
    Inferring Numerical Model Properties from Empirical Data2020Conference paper (Other academic)
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  • 27.
    Bazzi, Mohamad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology. University of Zurich.
    Campione, Nicolás E.
    Kear, Benjamin P.
    Uppsala University, Music and Museums, Museum of Evolution.
    Pimiento, Catalina
    Ahlberg, Per E.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Feeding ecology has shaped the evolution of modern sharks2021In: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 31, no 23, p. 5138-5148.e4Article in journal (Refereed)
    Abstract [en]

    Sharks are iconic predators in today’s oceans, yet their modern diversity has ancient origins. In particular, present hypotheses suggest that a combination of mass extinction, global climate change, and competition has regulated the community structure of dominant mackerel (Lamniformes) and ground (Carcharhiniformes) sharks over the last 66 million years. However, while these scenarios advocate an interplay of major abiotic and biotic events, the precise drivers remain obscure. Here, we focus on the role of feeding ecology using a geometric morphometric analysis of 3,837 fossil and extant shark teeth. Our results reveal that morphological segregation rather than competition has characterized lamniform and carcharhiniform evolution. Moreover, although lamniforms suffered a long-term disparity decline potentially linked to dietary “specialization,” their recent disparity rivals that of “generalist” carcharhiniforms. We further confirm that low eustatic sea levels impacted lamniform disparity across the end-Cretaceous mass extinction. Adaptations to changing prey availability and the proliferation of coral reef habitats during the Paleogene also likely facilitated carcharhiniform dispersals and cladogenesis, underpinning their current taxonomic dominance. Ultimately, we posit that trophic partitioning and resource utilization shaped past shark ecology and represent critical determinants for their future species survivorship.

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  • 28. Benjamin, Bolduc
    et al.
    Hodgkins, Suzanne B.
    Varner, Ruth K.
    Crill, Patrick M.
    McCalley, Carmody K.
    Chanton, Jeffrey P.
    Tyson, Gene W.
    Riley, William J.
    Palace, Michael
    Duhaime, Melissa B.
    Hough, Moira A.
    Saleska, Scott R.
    Sullivan, Matthew B.
    Rich, Virginia I.
    The IsoGenie database: an interdisciplinary data management solution for ecosystems biology and environmental research2020In: PeerJ, E-ISSN 2167-8359, Vol. 8, article id 9467Article in journal (Refereed)
    Abstract [en]

    Modern microbial and ecosystem sciences require diverse interdisciplinary teams that are often challenged in “speaking” to one another due to different languages and data product types. Here we introduce the IsoGenie Database (IsoGenieDB; https://isogenie-db.asc.ohio-state.edu/), a de novo developed data management and exploration platform, as a solution to this challenge of accurately representing and integrating heterogenous environmental and microbial data across ecosystem scales. The IsoGenieDB is a public and private data infrastructure designed to store and query data generated by the IsoGenie Project, a ~10 year DOE-funded project focused on discovering ecosystem climate feedbacks in a thawing permafrost landscape. The IsoGenieDB provides (i) a platform for IsoGenie Project members to explore the project’s interdisciplinary datasets across scales through the inherent relationships among data entities, (ii) a framework to consolidate and harmonize the datasets needed by the team’s modelers, and (iii) a public venue that leverages the same spatially explicit, disciplinarily integrated data structure to share published datasets. The IsoGenieDB is also being expanded to cover the NASA-funded Archaea to Atmosphere (A2A) project, which scales the findings of IsoGenie to a broader suite of Arctic peatlands, via the umbrella A2A Database (A2A-DB). The IsoGenieDB’s expandability and flexible architecture allow it to serve as an example ecosystems database.

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  • 29.
    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)
  • 30.
    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.

  • 31.
    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.

  • 32.
    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.

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  • 33. Bird, Anna
    et al.
    Millar, Ian
    Rodenburg, Tanja
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Department of Geography, Royal Holloway University of London.
    Rittner, Martin
    Vermeesch, Pieter
    Lu, Huayu
    A constant Chinese Loess Plateau dust source since the late Miocene2020In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 227, article id 106042Article in journal (Refereed)
    Abstract [en]

    The Pliocene-Pleistocene boundary marks a major change in global climate and East Asian monsoon dynamic. However, the role of the global atmospheric dust-cycle over this time is unclear; in particular the degree to which changes in the dust cycle influenced climate change, were driven by climate change, and how these processes interacted. Chinese loess records past dust-cycle history and the influences of aridification and monsoon circulation over the last 40 Ma. Previous work on the Chinese Loess Plateau argue over whether changes in dust source occur at the Pliocene-Pleistocene boundary, or at 1.2 Ma, despite these intervals marking major shifts in monsoon dynamics. We present Sr, Nd and Hf isotope data from multiple sites and show that dust source largely remains unchanged across these boundaries. Shifts in geochemistry are due to changes in grain-size and weathering. While the transport pathway (river, deserts, direct aeolian) is unclear, these tracer isotopes show that dust was dominantly sourced from the Northern Tibetan Plateau, with some input from the local bedrock. This shows that a major established and constant dust source on the Tibetan Plateau has been active and unchanged since late Miocene, despite dramatically changing climate conditions. Changes in loess accumulation are a function of climate change in Tibetan Plateau source regions rather than effects from increased aridification over the Pliocene-Pleistocene boundary.

  • 34. 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)
  • 35.
    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.

  • 36.
    Bjorneras, Caroline
    et al.
    Lund Univ, Dept Geol, Quaternary Sci, Lund, Sweden.;Lund Univ, Dept Biol, Aquat Ecol, Lund, Sweden..
    Weyhenmeyer, Gesa A.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Hammarlund, Dan
    Lund Univ, Dept Geol, Quaternary Sci, Lund, Sweden..
    Persson, Per
    Lund Univ, Ctr Environm & Climate Res CEC, Lund, Sweden.;Lund Univ, Dept Biol, Microbial Ecol Grp, Lund, Sweden..
    Kritzberg, Emma S.
    Lund Univ, Dept Biol, Aquat Ecol, Lund, Sweden..
    Sediment Records Shed Light on Drivers of Decadal Iron Concentration Increase in a Boreal Lake2022In: Journal of Geophysical Research - Biogeosciences, ISSN 2169-8953, E-ISSN 2169-8961, Vol. 127, no 3, article id e2021JG006670Article in journal (Refereed)
    Abstract [en]

    Increasing iron (Fe) concentrations are found in lakes on a wide geographical scale but exact causes are still debated. The observed trends might result from increased Fe loading from the terrestrial catchment, but also from changes in how Fe distributes between the water column and the sediments. To get a better understanding of the causes we investigated whether there has been any change in the sediment formation of Fe sulfides (FeS) as an Fe sink in response to declining atmospheric sulfur (S) deposition during recent decades. For our study, we chose Lake Bolmen in southern Sweden, a lake for which we confirmed that Fe concentrations in the water column have strongly increased along with water color during 1966-2018. Our investigations showed that Fe accumulation and speciation varied independently of S accumulation patterns in the Lake Bolmen sediment record. Thus, we were not able to relate the positive trend in Fe concentrations to reduced FeS binding in the sediments. Furthermore, we found that Fe accumulation rates increased along with lake water Fe concentrations, indicating that increased catchment loading rather than a change in the distribution between the sediments and the water column has driven the increase in Fe concentrations. The increased loading may be due to land-use change in the form of an extensive expansion of coniferous forest during the past century. Altered forest management practices and increased precipitation may have led to enhanced weathering and erosion of organic soil layers under aging coniferous forest.

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  • 37.
    Blicharska, Malgorzata
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development.
    Smithers, Richard J.
    Ricardo Energy & Environment, Ricardo plc, Gemini Building, Didcot, UK.
    Kuchler, Magdalena
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development.
    Munaretto, Stefania
    KWR Water Research Institute, Nieuwegein, The Netherlands.
    van den Heuvel, Lotte
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Teutschbein, Claudia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    The water–energy–food–land–climate nexus: Policy coherence for sustainable resource management in Sweden2023In: Environmental Policy and Governance, ISSN 1756-932X, E-ISSN 1756-9338Article in journal (Refereed)
    Abstract [en]

    The concept of a ‘nexus’ across issues regarding the management of natural resources has gained increasing academic attention in recent years, but there is still relatively limited research on the application of the nexus approach for evaluating policies. This study analyses coherence among the main goals of five policy areas (water, energy, food, land, and climate) in Sweden, drawing upon a desk review, expert assessment, and interaction with stakeholders. The main objective is to enhance understanding of opportunities and challenges posed by such a nexus, understand policy interactions in Sweden, and provide insights into the use of policy coherence analysis as an integral part of resource nexus assessments. The analysis reveals synergies and conflicts between policy goals. For example, Sweden's environmental quality objectives (EQOs) regarding land and all the goals regarding water are either synergistic or neutral. Likewise, climate policy goals are well aligned with the goals regarding energy and ground water quality. On the other hand, the key goal for agriculture, which is food production, is the least coherent with those of the other policy areas. There are conflicts between the EQOs and goals regarding agricultural and forestry production. Stakeholders also indicate that climate goals are treated with higher priority than the goals of other policy areas. Notably, some interactions between policy goals are synergistic or conflicting depending on the context or their interpretation. Implementation of existing goals depends on relevant stakeholders' interests, priorities and interpretations, and on existing prevailing discourses in society, often supported by higher level policies.

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  • 38.
    Blicharska, Malgorzata
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development.
    Teutschbein, Claudia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Smithers, Richard J.
    Ricardo Energy & Environment, University of Sheffield.
    SDG partnerships may perpetuate the global North–South divide2021In: Scientific Reports, E-ISSN 2045-2322, Vol. 11, no 1, article id 22092Article in journal (Refereed)
    Abstract [en]

    The 2030 Agenda for Sustainable Development gives equal emphasis to developed (“Northern”) countries and developing (“Southern”) countries. Thus, implementation of the Sustainable Development Goals (SDGs) demands coherent collaboration to transform society across all countries. Yet, there has been little research published on SDG partnerships and this is the first study to explore the extent to which partners from Northern and Southern countries are involved in them and their focus. It identifies that involvement is unequally distributed and may perpetuate the North–South divide in countries’ resources, including access to data and scientific capacities. Most notably, partners from low-income countries are involved in far fewer partnerships than partners from countries in all other World Bank income categories, although the former are least able to develop sustainably. As such, all those promoting sustainable development from governmental, private and third-sector organisations need to address global inequalities in establishing and implementing SDG partnerships if, collectively, they are to facilitate delivery of Agenda 2030.

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  • 39.
    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)
  • 40.
    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)
  • 41. Bohm, Katja
    Modern-type Paleogene Eolian Regime and Dust Provenance in Central-East Asia Linked to Northern Hemisphere GlaciationManuscript (preprint) (Other academic)
  • 42.
    Bohm, Katja
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Department of Geosciences and Geography, University of Helsinki, Helsinki, Finland.
    Wasiljeff, J
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Department of Geosciences and Geography, University of Helsinki, Helsinki, Finland.
    Salminen, J
    Tang, Hui
    Lahaye, Y
    Kurhila, M
    Zhang, Z
    Haugvaldstad5, O
    Kaakinen, A
    Modern-type Paleogene Eolian Regime and Global Cooling-Modulated Dust Provenance in Late Paleogene of Central-East Asia2024In: Geochemistry Geophysics Geosystems, E-ISSN 1525-2027, Vol. 25, no 2, article id e2023GC011167Article in journal (Refereed)
    Abstract [en]

    Atmospheric mineral dust is a poorly constrained yet extremely important component of the climate system. Provenance studies from geologic dust archives are crucial to understand the drivers of the dust cycle over long time scales. Our multi-technique provenance analysis of a rare Paleogene (35–27 Ma) eolian dust sequence from Ulantatal, ∼400 km northwest of the Chinese Loess Plateau (CLP), shows that Paleogene dust transporting winds generally varied between northwesterly and westerly, the same as those in the late Neogene-Quaternary bipolar icehouse. We propose that, as today, westerly wind circulation patterns would have been modulated by an Arctic Oscillation (AO)-like situation, and that the warm Eocene favored a long-term negative phase of AO, leading to meridional westerly circulation and the dominance of a northwesterly dust transport pathway. After the Eocene-Oligocene transition (EOT), long-term positive phase of AO-like conditions initiated, leading to stronger and more zonal westerlies. The Siberian High (SH) also formed or strengthened at the EOT and started to control dust storm activity along the northwesterly transport pathway. We argue that increased Paleogene Northern Hemisphere (NH) ice volume was the ultimate driver of this modern-type dust transport regime in the Ulantatal region, possibly also controlling initial Ulantatal dust sequence formation via the development of the SH and modern-type eolian regime. The similarity between the Ulantatal and late Neogene northern CLP dust provenance signals suggests that the increased NH ice volume, via its control on the northwesterly dust transport, could have promoted increased loess formation also in the late Miocene.

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  • 43. 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)
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  • 44.
    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).

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  • 45. 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)
  • 46.
    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, E-ISSN 2056-2802, 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.

  • 47. Bradak, Balazs
    et al.
    Gomez, Christopher
    Kereszturi, Ákos
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Searching for potential multi-hazard events during the last 1.5 million years of the Pleistocene epoch2022In: Forum Geografi, ISSN 0852-0682, Vol. 36, no 1, p. 39-53Article in journal (Refereed)
    Abstract [en]

    Increasing attention has been paid to multi-hazards in environmental disaster studies produced during thelast decade. Multi-hazard studies focus on the occurrence, interaction and effect of several natural hazardsin the same region. Despite the increasing number of multi-hazard studies, few investigations have focusedon global-scale multi-hazard events. With the aim of closing this gap, our study focuses on the identificationof periods during the last 1.5 million years of the Pleistocene epoch, with the quasi-parallel appearance ofnatural hazards (e.g., asteroid impacts and large volcanic eruptions with a Volcanic Explosivity Index (VEI)of 8 and 7) amplifying their individual effects and thus causing long-term, global-scale changes. Of the sevenidentified potential multi-hazard events, three were considered as possible global-scale events with a longerterm environmental (paleoclimatic) impact; dated to c.a., 1.4 Ma (marine isotope stage – MIS45), 1.0 Ma(MIS 27), and 100 ka (MIS 5c), respectively. Two additional periods (around 50 and 20 ka) were identifiedas being associated with more restricted scale multi-hazard events, which might cause a “Little Ice Age-like”climatic episode in the history of the Pleistocene Period. In addition, we present a hypothesis about thecomplex climatic response to a global-scale multi-hazard event consisting of a series of asteroid impacts andvolcanic eruption linked to a geomagnetic polarity change, namely the Matuyama-Brunhes Boundary, whichmight be accompanied by global cooling and result in the final step of the Early Middle Pleistocene Transition.

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  • 48. Bradák, B.
    et al.
    Újvári, G.
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Bógalo, M.F.
    González, M.I.
    Hyodo, M.
    Gomez, C.
    Potential drivers of disparity in early Middle Pleistocene interglacial climate response over Eurasia2022In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 585, article id 110719Article in journal (Refereed)
    Abstract [en]

    Poor understanding of the differential evolution of interglacial climate over various regions in Eurasia greatly limits our ability to predict the specific local impacts of future climate change. Here we demonstrate starkly opposing trends in interglacial intensities in Asia and Europe over the early Middle Pleistocene and Mid-Brunhes Transitions based on the study of various climate proxies in the Paks loess record (Hungary), a key profile in the European Loess Belt. These contrasting climate trends imply major but unexplained differences in the regional response of Quaternary climate to shifts in forcing mechanisms during two major reorganizations of Earth's climate across Eurasia. Using new rock magnetic datasets from the Paks record we suggest that the changing dominance of Mediterranean, Atlantic (Westerlies) and continental air masses under the influence of the quasi permanent high pressure centres over the Fennoscandian ice sheet played a key role in the observed differences in the evolution of early Middle Pleistocene climate. We also propose that the intensification of the early Middle Pleistocene glaciation of Central Asian mountains may have strengthened and shifted the Siberian High west-ward on multi-millennial/orbital timescales, which in turn forced geographically contrasting expressions of the MIS 19 to 11 interglacials in Eurasia. This is the first coherent explanation for the geographically diverse response of regional climate to the early Middle Pleistocene climate transitions and points to the clear role of global cooling and expanded mid-latitude glaciers in driving these events.

  • 49. Bradák, Balázs
    et al.
    Seto, Yusuke
    Stevens, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Újvári, Gábor
    Fehér, Katalin
    Költringer, Chiara
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Magnetic susceptibility in the European Loess Belt: New and existing models of magnetic enhancement in loess2021In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 569, article id 110329Article in journal (Refereed)
    Abstract [en]

    Magnetic susceptibility measurements play a key role in Quaternary studies. Magnetic proxies, such as low field and frequency-dependent magnetic susceptibility, are widely applied in the reconstruction of terrestrial paleoclimate, e.g., in the study of loess-paleosol successions. In general, the interpretation of loess magnetic susceptibility signals is based on two commonly accepted models: the pedogenic magnetic enhancement and wind-vigour models. However, there are an increasing number of cases where such models cannot be used. These cases show unusual relationships between the two common loess magnetic susceptibility proxies: low field and frequency-dependent magnetic susceptibility. Such relationships have been attributed to various phenomena including the dissolution of fine-grain minerals and the formation of ultrafine magnetic rims on the surface of coarser grains by weathering. Despite the growing number of these exceptional cases of magnetic enhancement, our knowledge about the occurrence and potential causes of the unusual behaviour of magnetic susceptibility parameters is still limited. This, in turn, hinders the wider application of magnetic susceptibility parameters in loess. To fill this knowledge gap, magnetic susceptibility data of various profiles from the European Loess Belt were collected and compared to reveal various enhancement trends in loess. Along with the analysis of magnetic susceptibility parameters, combined scanning electron microscopy (SEM) and rock magnetic analyses were applied to samples from the Paks loess sequence in Hungary to describe some of the irregular cases, notably the cause of increasing frequency-dependent susceptibility in non-altered sediments. Analysis of loess, paleosol and common mineral samples separated from loess (e.g., muscovite) revealed that various features may be responsible for these increasing frequency-dependent susceptibility values: i) surface weathering (maghemitization) of coarser detrital grains, ii) nanofragmentation by physical weathering and iii) the appearance of significant amounts of ultrafine magnetic inclusions in micas. These special modes of magnetic enhancement of loess do not undermine the importance of the basic theories suggested above, but rather provide three mechanisms that account for some of the increasing number of unusual cases. To aid in the wider and more accurate use of magnetic susceptibility parameters in loess, we review the current magnetic enhancement models with special emphasis on the identification of unusual trends in magnetic enhancement and understanding their drivers.

  • 50.
    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.

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