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  • 701.
    Zhang, Zhifei
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Holmer, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Wang, Haizhou
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Butler, Aodhán D.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    An early Cambrian agglutinated tubular lophophorate with brachiopod characters2014In: Scientific Reports, E-ISSN 2045-2322, Vol. 4, p. 4682-Article in journal (Refereed)
    Abstract [en]

    The morphological disparity of lophotrochozoan phyla makes it difficult to predict the morphology of the last common ancestor. Only fossils of stem groups can help discover the morphological transitions that occurred along the roots of these phyla. Here, we describe a tubular fossil Yuganotheca elegans gen.et sp. nov. from the Cambrian (Stage 3) Chengjiang Lagerstätte (Yunnan, China) that exhibits an unusual combination of phoronid, brachiopod and tommotiid (Cambrian problematica) characters, notably a pair of agglutinated valves, enclosing a horseshoe-shaped lophophore, supported by a lower bipartite tubular attachment structure with a long coelomic pedicle providing anchorage. The discovery has important implications for the early evolution of lophotrochozoans, suggesting rooting of brachiopods into the sessile lophotrochozoans and the origination of their bivalved bauplan preceding the biomineralization of shell valves in crown brachiopods.

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    Zhang_etal_2014
  • 702.
    Zhang, Zhifei
    et al.
    Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China..
    Liang, Yue
    Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China..
    Liu, Fan
    Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China..
    Hu, Yazhou
    Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China..
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China.
    Reconstruction of the first consumer-driven marine ecosystem on Earth, perspectives from early Cambrian small skeletal fossils from China2023In: Estonian journal of earth sciences, ISSN 1736-4728, E-ISSN 1736-7557, Vol. 72, no 1, article id 169Article in journal (Other academic)
    Abstract [en]

    Biological activity was the major triggering factor driving Earth's organic and inorganic cycles across the biosphere, lithosphere, and atmosphere. A key question in the evolution of Earth's ecosystem is when and how different animals emerged and flourished and how their appearance impacted the hydrosphere-atmosphere-lithosphere cycles. The Cambrian Explosion of meta -zoans in the Ediacaran-Cambrian boundary interval resulted in sudden appearance of most of the readily fossilizable modern animal groups as macro-consumers in the Earth's oceans. This explosive radiation event led for the first time to the emergence and diversification of animals on Earth, to the establishment of complex trophic webs with animals as consumers, and marks the onset of the Phanerozoic oceanic ecosystem. Our presentation aims to discuss the at least half-billion-year-old world of tubular and conical shelled organisms (sponges, conulariids, chancelloriids, hyoliths, mollusks, tommotiids, and other lophotrochozoans) that are unseen in the present-day oceans but were recovered by us from the siliciclastic and carbonate rocks in and outside of China. Additionally, to study the body fossils of exceptionally preserved biotas (Konversat-Lagerstätten) across China, efforts are underway to understand how the early animals, notably early bilaterians, created the over 500-million-year-old oceanic ecosystems without the influence of land plants, which appeared later.

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    FULLTEXT01
  • 703.
    Zhang, Zhi-Fei
    et al.
    Northwest Univ, State Key Lab Continental Dynam, Early Life Inst, Xian 710069, Peoples R China.
    Zhang, Zhi-Liang
    Northwest Univ, State Key Lab Continental Dynam, Early Life Inst, Xian 710069, Peoples R China.
    Li, Guo-Xiang
    Chinese Acad Sci, Nanjing Inst Geol & Palaeontol, LPS, Nanjing 210008, Jiangsu, Peoples R China.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    The Cambrian brachiopod fauna from the first-trilobite age Shuijingtuo Formation in the Three Gorges area of China2016In: Palaeoworld, ISSN 1871-174X, E-ISSN 1875-5887, Vol. 25, no 3, p. 333-355Article in journal (Refereed)
    Abstract [en]

    The Yangtze platform of South China offers evidence within its Ediacaran–Cambrian geological record of the Cambrian explosion and diversificationevents in metazoan history. To understand the explosive radiation of animals and the environments in which it took place, the basalCambrian fauna succession of the Aijiahe section in the Three Gorges area, western Hubei Province, has been studied, revealing the earliestbrachiopod fauna (Tsunyidiscus trilobite Zone) in this region, which was dominated numerically by acrotretoids. This is accompanied by abundantskeletal fossils including minute well-preserved phosphatized archaeocyath cups and an assortment of abundant sponge spicules, chancelloriids,mollusks, hyoliths, and bradoriids, retrieved by acid-etching limestone interbeds in the black shale-dominated Shuijingtuo Formation (Series 2).The brachiopods comprise two species of acrotretoids, two types of botsfordiids (Botsfordiidae gen. et sp. indet. A and B), and four species oflinguloids. Of the latter, Spinobolus popovi n. gen. n. sp. is strikingly distinctive and typified by spine-like ornamentation seen for the first time in thelower Cambrian; the remaining three linguloid genera, Palaeobolus, Eoobolus, and Lingulellotreta, have a trans-paleocontinental distribution. TheThree Gorges Shuijingtuo brachiopod assemblage differs from that of the upper Atdabanian Stage (Cambrian Stage 3) in Siberia and South China,but shows great similarities with those discovered in the Tsanglangpuan (equivalent to Botoman or Stage 4) Stage of eastern Yunnan Province,Siberia, and South Australia, suggesting a much more prolonged sedimentary hiatus in basalmost Shuijingtuo Formation of the Three Gorges areathan previously expected. The presence of such unconformities provides a caveat to stable isotope-based correlations that involve a number ofdiscussions of global ocean geochemical changes across the time interval that witnessed Cambrian explosion of metazoans.

  • 704.
    Zhang, Zhiliang
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Shaanxi Key laboratory of Early Life and Environments and Department of Geology, State Key Laboratory of Continental Dynamics, Northwest University, Xi’an, China.
    Popov, Leonid E.
    Department of Geology, National Museum of Wales, Cardiff, UK.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Shaanxi Key laboratory of Early Life and Environments and Department of Geology, State Key Laboratory of Continental Dynamics, Northwest University, Xi’an, China.
    Zhang, Zhifei
    Shaanxi Key laboratory of Early Life and Environments and Department of Geology, State Key Laboratory of Continental Dynamics, Northwest University, Xi’an, China.
    Earliest ontogeny of early Cambrian acrotretoid brachiopods: first evidence for metamorphosis and its implications2018In: BMC Evolutionary Biology, E-ISSN 1471-2148, Vol. 18, article id 42Article in journal (Refereed)
    Abstract [en]

    Our understanding of the ontogeny of Palaeozoic brachiopods has changed significantly during the last two decades. However, the micromorphic acrotretoids have received relatively little attention, resulting in a poor knowledge of their ontogeny, origin and earliest evolution. The uniquely well preserved early Cambrian fossil records in South China provide a great new opportunity to investigate the phylogenetically important ontogeny of the earliest acrotretoid brachiopods, and give new details of the dramatic changes in anatomy of acrotretoid brachiopods during the transition from planktotrophic larvae to filter feeding sedentary juveniles.

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  • 705.
    Zhang, Zhiliang
    et al.
    Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China.;Macquarie Univ, Dept Biol Sci, Sydney, NSW 2109, Australia.;Uppsala Univ, Inst Earth Sci, Palaeobiol, SE-75236 Uppsala, Sweden..
    Pour, Mansoureh Ghobadi
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Golestan Univ, Fac Sci, Dept Geol, Gorgan, Golestan, Iran.;Natl Museum Wales, Dept Geol, Cathays Pk, Cardiff CF10 3NP, Wales..
    Popov, Leonid E.
    Natl Museum Wales, Dept Geol, Cathays Pk, Cardiff CF10 3NP, Wales..
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China.
    Chen, Feiyang
    Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China.;Macquarie Univ, Dept Biol Sci, Sydney, NSW 2109, Australia..
    Chen, Yanlong
    Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China..
    Brock, Glenn A.
    Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China.;Macquarie Univ, Dept Biol Sci, Sydney, NSW 2109, Australia..
    Zhang, Zhifei
    Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Shaanxi Key Lab Early Life & Environm, Xian 710069, Peoples R China..
    The oldest Cambrian trilobite - brachiopod association in South China2021In: Gondwana Research, ISSN 1342-937X, E-ISSN 1878-0571, Vol. 89, p. 147-167Article in journal (Refereed)
    Abstract [en]

    Limestones of the Xihaoping Member of the Dengying Formation in the Xiaoyangba section, South China, yield the oldest known Cambrian brachiopod-trilobite association. In this member, the trilobite Parabadiella cf. huoi co-occurs with the new brachiopod species Eoobolus incipiens sp. nov. The association provides potential for correlation of lower Cambrian successions and gives novel insights into the origin, palaeobiogeographic distribution and early evolution of linguliform brachiopods. Parabadiella occurs in shallow marine clastic and carbonate rocks in South China, demonstrating a broad distribution for this taxon. The new discovery indicates an early Chiungchussuan age (Parabadiella trilobite Zone, Cambrian Age 3) for the longstanding problematic Xihaoping Member. Furthermore, this earliest Parabadiella-Eoobolus association helps to establish close links with the oldest knowntrilobite-brachiopod assemblage from the upper Micrina etheridgei Zone (Parabadiella huoi trilobite Zone) in Australia. Eoobolus incipiens represents one of the earliest known linguliform brachiopods, with a distinctive mixture of characters shared with both problematic tommotiids, as well as paterinide, lingulide and acrotretide brachiopods, indicating that these features may be plesiomorphic for the Linguliformea. An age-constrained dispersal mode for early lingulate brachiopods is proposed, indicating that the Subphylum Linguliformea may have originated in East Gondwana and South China during Cambrian Age 3, and only subsequently dispersed to other major Cambrian palaeocontinents (e.g. Siberia, Laurentia, Antarctica, Baltica, Avalonia, West Gondwana, North China) during the late stage of the Cambrian evolutionary radiation of animals. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of International Association for Gondwana Research.

  • 706.
    Zhen, Jinzhu
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Exploring the Impact of Eco-migration Project, Ordos, Inner Mongolia, CHina2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    To reverse the emergency environmental degradation of Ordos, Inner Mongolia, China, the localgovernment enforced a new developing project – Eco-migration, which aims at bothenvironmental restoration and poverty alleviation. Within ten years’ time, more than 400,000 ruralresidents were relocated. Through professional training and labor transportation, the financialcondition was largely improved. The annual income of these eco-migrants was highly raised from0.2 USD a day in 2000 to 3.51 USD a day in 2010. From the environmental perspective, morethan 70 percent of the sandy wasteland was restored. The vegetable coverage jumped up to 75percent, comparing to 30 percent in 2000. Through field study, the feedbacks from theseeco-migrants were collected. Eco-migrants were highly satisfied with the economic andenvironmental improvement. However, there are lots of improvements can be done. In one word,that’s the way the government trying to achieve the goal of sustainable development, whichproviding valuable experience for future.

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  • 707. Zheng, J.
    et al.
    Fisher, D.
    Blake, E.
    Hall, G.
    Vaive, J.
    Krachler, M.
    Zdanowicz, Christian M.
    Lam, J.
    Lawson, G.
    Shotyk, W.
    An ultra-clean firn core from the Devon Island Ice Cap, Nunavut, Canada, retrieved using a titanium drill specially designed for trace element studies2006In: Journal of Environmental Monitoring, Vol. 8, no 3, p. 406-413Article in journal (Refereed)
  • 708. Zheng, J.
    et al.
    Zdanowicz, Christian M.
    Fisher, D.
    Hall, G.
    Vaive, J.
    A new 155-year record of Pb pollution from Devon ice cap, Canada2003In: Journal De Physique. IV : JP, Vol. 107, no II, p. 1405-1408Article in journal (Refereed)
  • 709.
    Zhu, Min
    et al.
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China.;Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China..
    Ahlberg, Per E.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Pan, Zhaohui
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China.;Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China..
    Zhu, Youan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Qiao, Tuo
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    Zhao, Wenjin
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    Jia, Liantao
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    Lu, Jing
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    A Silurian maxillate placoderm illuminates jaw evolution2016In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 354, no 6310, p. 334-336Article in journal (Refereed)
    Abstract [en]

    The discovery of Entelognathus revealed the presence of maxilla, premaxilla, and dentary, supposedly diagnostic osteichthyan bones, in a Silurian placoderm. However, the relationship between these marginal jaw bones and the gnathal plates of conventional placoderms, thought to represent the inner dental arcade, remains uncertain. Here we report a second Silurian maxillate placoderm, which bridges the gnathal and maxillate conditions. We propose that the maxilla, premaxilla, and dentary are homologous to the gnathal plates of placoderms and that all belong to the same dental arcade. The gnathal-maxillate transformation occurred concurrently in upper and lower jaws, predating the addition of infradentary bones to the lower jaw.

  • 710.
    Zhu, You-an
    et al.
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key CAS Lab Vertebrate Evolut & Human Origins, Beijing, Peoples R China.;CAS Ctr Excellence Life & Paleoenvironm, Beijing, Peoples R China..
    Li, Qiang
    Qujing Normal Univ, Res Ctr Nat Hist & Culture, Qujing, Peoples R China.;Chongqing Inst Geol & Mineral Resources, Chongqing, Peoples R China..
    Lu, Jing
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key CAS Lab Vertebrate Evolut & Human Origins, Beijing, Peoples R China.;CAS Ctr Excellence Life & Paleoenvironm, Beijing, Peoples R China.;Univ Chinese Acad Sci, Coll Earth & Planetary Sci, Beijing, Peoples R China..
    Chen, Yang
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key CAS Lab Vertebrate Evolut & Human Origins, Beijing, Peoples R China.;Chongqing Inst Geol & Mineral Resources, Chongqing, Peoples R China..
    Wang, Jianhua
    Qujing Normal Univ, Res Ctr Nat Hist & Culture, Qujing, Peoples R China..
    Gai, Zhikun
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key CAS Lab Vertebrate Evolut & Human Origins, Beijing, Peoples R China.;CAS Ctr Excellence Life & Paleoenvironm, Beijing, Peoples R China..
    Zhao, Wenjin
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key CAS Lab Vertebrate Evolut & Human Origins, Beijing, Peoples R China.;CAS Ctr Excellence Life & Paleoenvironm, Beijing, Peoples R China.;Univ Chinese Acad Sci, Coll Earth & Planetary Sci, Beijing, Peoples R China..
    Wei, Guangbiao
    Chongqing Inst Geol Survey, Chongqing, Peoples R China..
    Yu, Yilun
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key CAS Lab Vertebrate Evolut & Human Origins, Beijing, Peoples R China.;Univ Chinese Acad Sci, Coll Earth & Planetary Sci, Beijing, Peoples R China..
    Ahlberg, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Zhu, Min
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key CAS Lab Vertebrate Evolut & Human Origins, Beijing, Peoples R China.;CAS Ctr Excellence Life & Paleoenvironm, Beijing, Peoples R China.;Univ Chinese Acad Sci, Coll Earth & Planetary Sci, Beijing, Peoples R China..
    The oldest complete jawed vertebrates from the early Silurian of China2022In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 609, no 7929, p. 954-958Article in journal (Refereed)
    Abstract [en]

    Molecular studies suggest that the origin of jawed vertebrates was no later than the Late Ordovician period (around 450 million years ago (Ma))(1,2). Together with disarticulated micro-remains of putative chondrichthyans from the Ordovician and early Silurian period(3-8), these analyses suggest an evolutionary proliferation of jawed vertebrates before, and immediately after, the end-Ordovician mass extinction. However, until now, the earliest complete fossils of jawed fishes for which a detailed reconstruction of their morphology was possible came from late Silurian assemblages (about 425 Ma)(9-13). The dearth of articulated, whole-body fossils from before the late Silurian has long rendered the earliest history of jawed vertebrates obscure. Here we report a newly discovered Konservat-Lagerstatte, which is marked by the presence of diverse, well-preserved jawed fishes with complete bodies, from the early Silurian (Telychian age, around 436 Ma) of Chongqing, South China. The dominant species, a `placoderm' or jawed stem gnathostome, which we name Xiushanosteus mirabilis gen. et sp. nov., combines characters from major placoderm subgroups(14-17) and foreshadows the transformation of the skull roof pattern from the placoderm to the osteichthyan condition(10). The chondrichthyan Shenacanthus uermiformis gen. et sp. nov. exhibits extensive thoracic armour plates that were previously unknown in this lineage, and include a large median dorsal plate as in placoderms(14-16), combined with a conventional chondrichthyan bauplan(18,19). Together, these species reveal a previously unseen diversification of jawed vertebrates in the early Silurian, and provide detailed insights into the whole-body morphology of the jawed vertebrates of this period.

  • 711.
    Zigaite, Zivile
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Whitehouse, Martin
    Naturhistoriska Riksmuseet Stockholm.
    Joachimski, Michael M.
    University of Erlangen Nuremberg.
    Sansom, Ivan
    University of Birmingham.
    Ahlberg, Per Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Oxygen isotopes in modern and fossil ecosystems: model and case study overview2016Conference paper (Other academic)
  • 712. Álvaro, J. Javier
    et al.
    Holmer, Lars E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. State Key Laboratory of Continental Dynamics, Shaanxi Key Laboratory of Early Life and Environments, Department of Geology, Northwest University, Xi’an, 710069, China.
    Shen, Yanan
    Popov, Leonid E.
    Ghobadi Pour, Mansoureh
    Zhang, Zhifei
    Zhang, Zhiliang
    Ahlberg, Per
    Bauert, Heikki
    González-Acebrón, Laura
    Submarine metalliferous carbonate mounds in the Cambrian of the Baltoscandian Basin induced by vent networks and water column stratification2022In: Scientific Reports, E-ISSN 2045-2322, Vol. 12, no 1, article id 8475Article in journal (Refereed)
    Abstract [en]

    Two massive precipitation events of polymetallic ore deposits, encrusted by a mixture of authigenic carbonates, are documented from the Cambrian of the semi-enclosed Baltoscandian Basin. δ34S (‒9.33 to ‒2.08‰) and δ33S (‒4.75 to ‒1.06‰) values from the basal sulphide breccias, sourced from contemporaneous Pb–Zn–Fe-bearing vein stockworks, reflect sulphide derived from both microbial and abiotic sulphate reduction. Submarine metalliferous deposits were triggered by non-buoyant hydrothermal plumes: plumes of buoyant fluid were trapped by water column stratification because their buoyancy with respect to the environment reversed, fluids became heavier than their surroundings and gravitational forces brought them to a halt, spreading out laterally from originating vents and resulting in the lateral dispersion of effluents and sulphide particle settling. Subsequently, polymetallic exhalites were sealed by carbonate crusts displaying three generations of ikaite-to-aragonite palisade crystals, now recrystallized to calcite and subsidiary vaterite. Th of fluid inclusions in early calcite crystals, ranging from 65 to 78 ºC, provide minimum entrapment temperatures for carbonate precipitation and early recrystallization. δ13Ccarb (‒1.1 to + 1.6‰) and δ18Ocarb (‒7.6 to ‒6.5‰) values are higher than those preserved in contemporaneous glendonite concretions (‒8.5 to ‒4.7‰ and ‒12.4 to ‒9.1‰, respectively) embedded in kerogenous shales, the latter related to thermal degradation of organic matter. Hydrothermal discharges graded from highly reduced, acidic, metalliferous, and hot (~ 150 ºC) to slightly alkaline, calcium-rich and warm (< 100 ºC), controlling the precipitation of authigenic carbonates.

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  • 713.
    Ålund, Anton
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Rural Electrification and Societal Impacts on Future Energy Demand in Bolivia: A Case Study in an Altiplano Community2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Social variables are a predominant force to community development in rural areas. However, research on how social aspects affect the energy situation as a community expands is to date limited. This study aims explore this void and investigate the following question:

    “What could be a feasible pathway to reach a sustainable and resilient future state in Micaya, based on the impact of key variables within three different sectors: education, health and production?”

    In this study, theories and models of rural electrification and scenario analysis are transposed and applied to community operated rural electrification in order to frame development. The investigation is restricted to focus on three social sectors, healthcare, education and production. Current literature confirmed that social aspects are missing in rural electrification programs. 

    Through interview and discussion with an established expert group important social variables have been identified in the study community. These variables lay the foundation for the scenario building used to define a desirable future in the case study community. It was found that the variables within the production sector are most influential to future developments in the study community. 

    The study revealed that energy access, especially access to electricity, is an essential condition for the development of rural communities. However, it does not guarantee an increase in productivity or effectiveness in social institutions in the absence of other development programs. The study also concludes that well-planned, carefully implemented rural electrification programs provide enormous benefits to rural people. Once an area has reached a certain level of development, further improvement of societal institutions depends on the availability of a secure and stable energy supply.

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  • 714.
    Öberg, Karin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    An Analysis and Interpretation of the Geoscience BC Trek Project Till Geochemical and Mineralogical Data to Determine the Surficial Geochemical Expression of Bedrock Au-Ag-Cu-Mo Mineralization on the Nechako Plateau, British Columbia, Canada.2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The mineral exploration in the interior of British Columbia is challenged by an extensive coverage of glacial sediments. The Geoscience British Columbia (GBC) Targeting Resources through Exploration and Knowledge (TREK) Survey has since 2013 collected till samples in the northern interior plateau of British Columbia, covering an area of approximately 25,000km2. The TREK area is largely covered by Miocene to Pleistocene age volcanic rocks that are underlain by older volcanic, sedimentary, and intrusive rocks of the Stikine Terrane, and also to a smaller extent in the east by rocks of the Cache Creek Terrane. Previous surficial mapping to aid mineral exploration has determined that the Pleistocene ice sheet advances have been mainly to the east-northeast. The British Columbia Geological Survey (BCGS) MINFILE database includes five developed prospects, seven prospects and 39 mineral showings in the TREK Project area. Styles of mineralization include late Cretaceous and Eocene epithermal Au and Ag deposits (e.g., Blackwater-Davidson, Capoose, Wolf, and 3T’s), lower Cretaceous sediment-hosted Carlin-type deposits (e.g. Bob) and Jurassic to Eocene porphyry Cu and Mo deposits (e.g., Endako and Chu). This report analyzes and interprets till digital data from three TREK Geoscience BC reports and one BCGS Open File to determine if there is a mineralogical and geochemical signature in the till of buried bedrock mineralization. Through statistical analysis, including scatter plots, probability plots, and box plots, populations of key ore indicators and pathfinder elements are compared, thresholds are established and anomalous samples queried. Spatial plots of samples with known pathfinder elements e.g. Au, Ag, Cu, and Mo values above established thresholds are created and compared with heavy mineral till concentrates such as pyrite and cinnabar. Major oxide element ratios from till sample whole rock analysis were also analyzed to identify hydrothermal alteration associated with the mineralization. The analysis has demonstrated that anomalous values reflect known bedrock mineralization and that there are two areas within the study area that do not appear to be related to already known mineral occurrences.

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    Öberg, Karin Kandidatuppsats
  • 715.
    Öhrlund, Isak
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Insamling av elektriskt och elektroniskt avfall: En fallstudie av två svenska kommuner2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Waste electrical and electronic equipment (WEEE) is the fastest growing waste stream within the EU, and at the same time of the most hazardous forms of waste, threatening both human health and the environment if not properly collected and treated. Sweden started a separate collection of WEEE in 2001, and with 16,27 kg of WEEE collected per person in 2011 it has one of the highest collection rates within the EU. Despite this, small WEEE is still ending up in all types of household waste. To solve this issue, the need for increased availability of collections points and information is frequently discussed, but despite improvements in these areas the content of WEEE in household waste remains relatively stable. The studies that make up the basis of today’s improvement work, have either been looking at shortcomings of the collection system from a national point of view, or on the effectiveness of alternative local collection systems. Based on these studies, conclusions about the general shortcomings of the system and potential ways of improvement have been drawn. At the same time, statistics show that the collection of WEEE differs substantially between different parts of Sweden, and that some municipalities have surprisingly efficient collection systems compared to others. With regard to his, current improvement strategies may not be optimal.

    Instead of looking at the strengths and weaknesses of specific collection systems, this study looks at the differences between two Swedish municipalities, one with a high and one with a low collection rate of small WEEE and compact fluorescent lamps, with the aim of creating a better understanding of factors that may contribute to high collection rates. The differences that are studied are the availability of collection points and the information in connection to these, the municipalities’ work and the resident’s knowledge, attitudes, preferences, subjective behavior and subjective perception of the collection system’s availability and functionality. Furthermore, the thesis examines whether the residents have been informed in accordance with European and national WEEE-legislation and what their attitudes and preferences are regarding a potential deposit system for small WEEE and compact fluorescent lamps.

    The results show that differences can be seen in all areas but the residents’ knowledge. From the observed differences, conclusions about possible ways of improving the collection of WEEE in Sweden are drawn. On a local level, increased municipal engagement and work efforts, in combination with increased access to collection points along with appropriate and well customized information in connection to these, is likely to increase the collection of WEEE. On a national level, increased supervision that forces municipalities to comply with the information requirements in European and national legislation, may lead to an increased awareness among Swedish citizens, which may in turn lead to a decrease in wrongly sorted small WEEE and compact fluorescent lamps. Finally, a potential deposit system for small WEEE and compact fluorescent lamps may be yet another way of increasing collection rates. The results suggest that a deposit system may in fact increase the motivation of citizens to recycle these products, decrease the amount of old electrical and electronic equipment currently stockpiled in private households, offer new possibilities to mark and track products and potentially lower the costs of collection.

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    Isak Öhrlund thesis 2012
  • 716.
    Gallet, Jean-Charles (Editor)
    Norwegian Polar Institute.
    Björkman, Mats P (Editor)
    University of Gothenburg.
    Larose, Catherine (Editor)
    Université de Lyon, Lyon, France.
    Luks, Bartłomiej (Editor)
    Polish Academy of Sciences.
    Martma, Tõnu (Editor)
    Talinn University of Technology.
    Zdanowicz, Christian (Editor)
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Protocols and recommendations for the measurement of snow physical properties,and sampling of snow for black carbon, waterisotopes, major ions and microorganisms2018Report (Other academic)
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