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Visar resultat 1 - 5 av 13 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Analysis of Seismic Data Acquired at the Forsmark Site for Storage of Spent Nuclear Fuel, Central Sweden

    Författare :Fatemeh Sharifi Brojerdi; Christopher Juhlin; Alireza Malehmir; Bjarne Almqvist; Ramon Carbonell; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Forsmark site; anisotropy; deformation zone; reflection seismic; shear-wave splitting; fractures and traveltime tomography;

    Sammanfattning : The Forsmark area, the main study area in this thesis, is located about 140 km north of Stockholm, central Sweden. It belongs to the Paleoproterozoic Svecokarelian orogen and contains several major ductile and brittle deformation zones including the Forsmark, Eckarfjärden and Singö zones. LÄS MER

  3. 2. Analyses of Seismic Wave Conversion in the Crust and Upper Mantle beneath the Baltic Shield

    Författare :Sverker Olsson; Roland Roberts; Hans Thybo; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geophysics; converted waves; Moho; upper mantle; Baltic Shield; tomography; anisotropy; receiver function; Geofysik;

    Sammanfattning : Teleseismic data recorded by broad-band seismic stations in the Swedish National Seismic Network (SNSN) have been used in a suite of studies of seismic wave conversion in order to assess the structure of the crust and upper mantle beneath the Baltic Shield. Signals of seismic waves converted between P and S at seismic discontinuities within the Earth carry information on the velocity contrast at the converting interface, on the depth of conversion and on P and S velocities above this depth. LÄS MER

  4. 3. Analyses and Application of Ambient Seismic Noise in Sweden : Source, Interferometry, Tomography

    Författare :Hamzeh Sadeghisorkhani; Ólafur Gudmundsson; Ari Tryggvason; Roland Roberts; Frederik Tilmann; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Seismic interferometry; Ambient noise; Surface wave; Wave propagation; Inverse theory; Sweden; Geofysik med inriktning mot seismologi; Geophysics with specialization in Seismology;

    Sammanfattning : Ambient seismic noise from generation to its application for determination of sub-surface velocity structures is analyzed using continuous data recordings from the Swedish National Seismic Network (SNSN). The fundamental aim of the thesis is to investigate the applicability of precise velocity measurements from ambient noise data. LÄS MER

  5. 4. Isotropic and Anisotropic P and S Velocities of the Baltic Shield Mantle : Results from Analyses of Teleseismic Body Waves

    Författare :Tuna Eken; Roland Roberts; Uli Achauer; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; teleseismic tomography; mantle lithosphere; seismic anisotropy; teleseismic earthquakes; shear wave splitting; Earth sciences; Geovetenskap; Geophysics Specialized In Seismology; geofysik; med inriktning mot seismologi;

    Sammanfattning : The upper mantle structure of Swedish part of Baltic Shield with its isotropic and anisotropic seismic velocity characteristics is investigated using telesesismic body waves (i.e. P waves and shear waves) recorded by the Swedish National Seismological Network (SNSN). LÄS MER

  7. 5. Strain quantifications in different tectonic scales using numerical modelling

    Författare :Lukas Fuchs; Hemin Koyi; Susanne Buiter; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Deformation modelling; progressive and finite deformation; salt tectonics; down-built diapir; upper mantle; lithosphere-asthenosphere boundary; seismic anisotropy; plate-mantle de coupling; Geovetenskap med inriktning mot mineralogi; petrologi och tektonik; Earth Science with specialization in Mineral Chemistry; Petrology and Tectonics;

    Sammanfattning : This thesis focuses on calculation of finite and progressive deformation in different tectonic scales using 2D numerical models with application to natural cases. Essentially, two major tectonic areas have been covered: a) salt tectonics and b) upper mantle deformation due to interaction between the lithosphere and asthenosphere. LÄS MER