Sökning: "near surface geophysics"

Visar resultat 1 - 5 av 23 avhandlingar innehållade orden near surface geophysics.

1. 1. Controlled Source Radiomagnetotelluric (CSRMT) Applications in Environmental and Resource Exploration

   Författare :Nazli Ismail; Laust Pedersen; Bulent Tezkan; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetotelluric; radio magnetotelluric; controlled-source tensor magnetotelluric; plane wave; near surface geophysics; sediment; fracture zone; inversion; forward modelling; near field effect; two-dimensional model; three-dimensional model; resolution; Geophysics; Geofysik; Earth Sciences with Specialization Environmental Analysis; geovetenskap med inriktning mot miljöanalys; Hydrology; hydrologi; mineralogi; petrologi och tektonik; Mineral Chemistry; Petrology and Tectonics;

   Sammanfattning : An integrated use of radio magnetotelluric (RMT) and controlled source tensor magnetotelluric (CSTMT) measurements, the so-called CSRMT method, has been employed in environmental and resource exploration studies. A number of case histories, including a groundwater investigation in glacial deposits, a study of fracture zones for geotechnical purposes and a mining exploration study of a copper deposit, are presented in this thesis in order to illustrate the usefulness and capability of the CSRMT method. LÄS MER

3. 2. Studies of Unusual Seismicity and Long Period Events at the Glacier Overlain Katla Volcano, Iceland

   Författare :Kristín Jónsdóttir; Roland Roberts; Björn Lund; Göran Ekström; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geophysics; Geofysik; Geophysics Specialized In Seismology; geofysik; med inriktning mot seismologi;

   Sammanfattning : Earthquake catalogues are usually dominated by diffusive behaviour consistent with the Omori law of aftershocks. This is investigated in terms of waiting times, i.e. the time between successive events in a time-sorted earthquake catalogue. LÄS MER

4. 3. Multidisciplinary Near-Surface Investigation of a Quick-Clay Landslide Prone Area in Southwest Sweden

   Författare :Silvia Salas Romero; Alireza Malehmir; Ian Snowball; Christopher Juhlin; Laura Valentina Socco; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Quick-clay; reflection seismic; landslide; southwest Sweden; borehole logging; physico-chemical properties; hydrogeological modelling; multichannel analysis of surface waves; magnetics; Geofysik med inriktning mot fasta jordens fysik; Geophysics with specialization in Solid Earth Physics;

   Sammanfattning : Quick-clay landslides are considered one of the most important geohazards in Sweden, Norway, and Canada. The deposits involved are glacial and postglacial clays and silty clays, which are very sensitive to increased stress that may collapse their structure and cause liquefaction. LÄS MER

5. 4. A Broad View on the Interpretation of Electromagnetic Data (VLF, RMT, MT, CSTMT)

   Författare :Behrooz Oskooi; Laust Börsting Pedersen; Thorkild Mack Rasmussen; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geophysics; Airborne; azimuthal anisotropy; CSTMT; distortion; EM; geothermal; Hengill; mineralization; MT; peaker; resolution; RMT; tipper; tensor VLF; VLF; Geofysik; Geophysics; Geofysik;

   Sammanfattning : The resolution power of single Very Low Frequency (VLF) data and multi-frequency Radiomagnetotelluric (RMT) data in delineating conductive structures typical for the sedimentary cover and crystalline basement in Scandinavia is studied with a view to future developments of the technique to increasing the frequency range into the LW radio band. Airborne and ground VLF data are interpreted and correlated with RMT measurements made on the ground to better understand the resolution power of VLF data. LÄS MER

7. 5. High-Resolution Seismics Methods Applied to Till Covered Hard Rock Environments

   Författare :Björn Bergman; Christopher Juhlin; Laust Börsting Pedersen; Ari Tryggvason; Ramon Carbonell; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geophysics; High-Resolution; Reflection Seismics; Tomography; Nuclear waste repository; Bedrock; Sediments; Geofysik; Geophysics; Geofysik;

   Sammanfattning : Reflection seismic and seismic tomography methods can be used to image the upper kilometer of hard bedrock and the loose unconsolidated sediments covering it. Developments of these two methods and their application, as well as identifying issues concerning their usage, are the main focus of the thesis. LÄS MER