Sökning: "Geophysics"
Visar resultat 6 - 10 av 210 avhandlingar innehållade ordet Geophysics.
6. Studies of Unusual Seismicity and Long Period Events at the Glacier Overlain Katla Volcano, Iceland
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
7. Seismic imaging of deep crustal reflectivity in Sweden and Iceland
Sammanfattning : Seismic reflection profiling, originally developed by the petroleum industry, was adapted to systematic imaging of deep structures some 25 years ago. In continental areas, these measurements often show weakly reflective upper crust and strongly reflective lower crust. LÄS MER
8. Prediction of Strong Ground Motion and Hazard Uncertainties
Sammanfattning : The purpose of this thesis is to provide a detailed description of recent methods and scientific basis for characterizing earthquake sources within a certain region with distinct tectonic environments. The focus will be on those characteristics that are most significant to the ground-shaking hazard and on how we can incorporate our current knowledge into hazard analyses for engineering design purposes. LÄS MER
9. Plane wave electromagnetic measurements for imaging fracture zones
Sammanfattning : Electromagnetic fields from distant radio transmitters interact with the resistivity structures in the earth. They can be regarded as plane-wave fields since their penetration depth is much smaller than their wavelength. LÄS MER
10. EnviroMT : A new controlled source/radio magnetotoelluric system
Sammanfattning : In the frame of an EU project, a new electromagnetic prospecting instrument was designed and constructed for environmental and engineering applications. The instrument works in the frequency domain in the band 1-250 kHz, whereby the collected data can be used to study the variation of ground resistivity from the surface to a maximum depth of few hundred meters. LÄS MER