Sökning: "geological time"

Visar resultat 16 - 20 av 176 avhandlingar innehållade orden geological time.

1. 16. Solute transport through fractured rocks : the influence of geological heterogeneities and stagnant water zones

   Författare :Batoul Mahmoudzadeh; Longcheng Liu; Ivars Neretnieks; David Hodgkinson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : To describe reactive solute transport and retardation through fractured rocks, three models are developed in the study with different focuses on the physical processes involved and different simplifications of the basic building block of the heterogeneous rock domain. The first model evaluates the effects of the heterogeneity of the rock matrix and the stagnant water zones in part of the fracture plane. LÄS MER

3. 17. Numerical modeling of groundwater and air flow between compacted bentonite and fractured crystalline rock

   Författare :Benoît Dessirier; Jerker Jarsjö; Andrew Frampton; Stefan Finsterle; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Two-phase flow; porous media; fractured media; compacted bentonite; crystalline rock; numerical modeling; geological disposal; Physical Geography; naturgeografi;

   Sammanfattning : The geological repository for final storage of spent nuclear fuel, envisioned by the Swedish Nuclear Fuel and Management Company (SKB), relies on several barriers: copper canisters deposited in holes in the floor of underground tunnels in deep bedrock, embedded in a buffer of compacted bentonite. The initially unsaturated buffer would take up water from the surrounding rock mass and swell to seal any potential gap. LÄS MER

4. 18. 3D Time-lapse Analysis of Seismic Reflection Data to Characterize the Reservoir at the Ketzin CO2 Storage Pilot Site

   Författare :Fei Huang; Christopher Juhlin; Alireza Malehmir; Ari Tryggvason; Andy Chadwick; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; CO2 storage; 3D Time-lapse 4D ; Reservoir characterization; Seismic simulation; Spectral decomposition; Wavelet phase; Tuning frequency; Thin-layer thickness; Seismic monitoring; Seismic processing; Quantitative interpretation; Geofysik med inriktning mot fasta jordens fysik; Geophysics with specialization in Solid Earth Physics;

   Sammanfattning : 3D time-lapse seismics, also known as 4D seismics, have great potential for monitoring the migration of CO2 at underground storage sites. This thesis focuses on time-lapse analysis of 3D seismic reflection data acquired at the Ketzin CO2 geological storage site in order to improve understanding of the reservoir and how CO2 migrates within it. LÄS MER

5. 19. Advances in time-domain induced polarization monitoring with application on chlorinated solvents contamination : Towards scalable real-time geophysical monitoring

   Författare :Aristeidis Nivorlis; Teknisk geologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geoelectrical monitoring; Chlorinated solvents; geophysics; Electrical resistivity tomography ERT ; Contaminated soil; contamination remediation geophysics;

   Sammanfattning : Environmental pollution is a significant concern for scientists, practitioners, authorities and the society. Among the various pollutants, chlorinated solvents pose a considerable risk to our groundwater resources. LÄS MER

7. 20. Modeling Solute Transport in Fractured Rocks-Role of Heterogeneity, Stagnant Water Zone and Decay Chain

   Författare :Batoul Mahmoudzadeh; Longcheng Liu; Joaquin Martinez; Lanru Jing; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Solute transport model; Fractured rock; Stagnant water zone; Rock matrix diffusion; Radionuclide decay chain; Geological layers; Laplace transform; Simulation;

   Sammanfattning : A model is developed to describe solute transport and retention in fractured rocks. It accounts for the fact that solutes not only can diffuse directly from the flowing channel into the adjacent rock matrix composed of different geological layers but can also at first diffuse into the stagnant water zone occupied in part of the fracture and then from there into the rock matrix adjacent to it. LÄS MER