Sökning: "upper mantle"
Visar resultat 1 - 5 av 19 avhandlingar innehållade orden upper mantle.
1. Analyses of Seismic Wave Conversion in the Crust and Upper Mantle beneath the Baltic Shield
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
2. Strain quantifications in different tectonic scales using numerical modelling
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
3. Recovering Moho parameters using gravimetric and seismic data
Sammanfattning : Isostasy is a key concept in geoscience to interpret the state of mass balance between the Earth’s crust and mantle. There are four well-known isostatic models: the classical models of Airy/Heiskanen (A/H), Pratt/Hayford (P/H), and Vening Meinesz (VM) and the modern model of Vening Meinesz-Moritz (VMM). LÄS MER
4. Isotropic and Anisotropic P and S Velocities of the Baltic Shield Mantle : Results from Analyses of Teleseismic Body Waves
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
5. Experimental investigation of hydrocarbon formation and transformation under Earth´s upper mantle conditions
Sammanfattning : The theory of the abyssal abiotic petroleum origin considers oil and natural gas to begenerated in the Earth’s upper mantle. Hydrocarbons migrate further through the deep faults into the Earth’s crust, where they can form oil and gas deposits in any kind of rock in any kind of structural position. LÄS MER