Sökning: "diagenesis"

Visar resultat 11 - 15 av 23 avhandlingar innehållade ordet diagenesis.

  1. 11. Studies of an elusive element : processes that influence the net retention of mercury in lake sediments and peatlands

    Författare :Johan Rydberg; Richard Bindler; Carl Lamborg; Umeå universitet; []
    Nyckelord :Mercury; retention; lake sediments; peatlands; environmental archives; sedimentation; diagenesis; vegetation; permafrost; Environmental Science; miljövetenskap;

    Sammanfattning : Because of its toxic nature mercury is a threat to both wildlife and human health, and thus, it is an element of concern in the environment. Currently much of the mercury emitted to the atmosphere is derived from anthropogenic sources – both direct emissions and re-emission of already deposited anthropogenic mercury. LÄS MER

  3. 12. Transformation of iron constituents during early diagenesis : in situ studies of a Baltic Sea sediment-water interface

    Författare :C. H. Magnus Lindström; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The aim of the present study was to elucidate the mechanisms and kinetics of the transformation of iron constituents at the sediment-water interface and their interaction with other element cycles during early diagenesis, with emphasis on their relations with oxygen, phosphorus and sulphur. The investigation was carried out in situ at 10 m water depth on a nearshore Baltic Sea soft bottom sediment. LÄS MER

  4. 13. Mineral diagenesis and petrology of the Dala Sandstone, central Sweden

    Författare :Ala Aldahan; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The Dala Sandstone, of Proterozoic age, is the most extensive sedimentary unit in central Sweden. The rocks are quartz sandstones, lithic sandstones, feldspathic sandstones, arkoses and greywackes with intercalations of shales and siltstones less than 1 m thick. The Öje Basalt divides the sedimentary sequence into two parts. LÄS MER

  5. 14. The fate of nitrogen in early diagenesis of Baltic sediments : a study of the sediment-water interface

    Författare :Anna-Greta Engvall; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : .... LÄS MER

  7. 15. Transport by Benthic Macrofauna: Functional Classification and Biogeochemical Response

    Författare :Stina Lindqvist; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Marine sediments; Early diagenesis; Bioturbation; Functional groups; Benthic fluxes; Imaging; Ecosystem function; Sediment reworking; Transport proxies; Fluorescent particles;

    Sammanfattning : Burrowing and reworking activities by benthic macrofauna regulate rates and pathways during organic matter mineralisation in bioturbated sediments. In so doing, they also affect the overall cycling of elements crucial in the biosphere (e.g. C, N, P, Fe, Mn and S). LÄS MER