Oversikt over dr.ing./Ph.D.-kandidater
Structural geology and deformation pattern of rock-slope instabilities:
Optimisation of methods for hazard analysis
To understand the structural control and the deformation pattern of rock-slope instabilities properly, it is necessary to look at an entire region and to prevent focusing exclusively on single sites. Moreover not all structures might be visible at all scales. For this reason, the PhD project will comprise regional scale studies up to site-specific studies and the link between both will be investigated, taking into account the potential of new techniques, like Lidar (Light Detection and Ranging) and SAR (Synthetic Aperture Radar), that are up to now not investigated in detail. Furthermore, the results from regional and local approaches will be compared and scale dependencies can be evaluated.
Historical data and geological studies show that a high concentration of post-glacial gravitational slope failures as well as current instabilities can be found in the
Norwegian counties Møre & Romsdal and Sogn & Fjordane, both situated in Western
Norway. For this reason the study site for this PhD thesis is placed in this region.
The first step of this PhD project will be a regional approach for locating rock-slope instabilities. Assuming that future rockslides will occur under similar geological and geometrical circumstances as past rockslides have occurred, it is essential to study ancient and also currently known rock-slope instabilities to limit the effect of big catastrophes in the future. For this reason, the critical parameters involved in the development of rockslides in certain regions of Western Norway will be determined and quantitative spatial relationships between the occurrences of rockslides and their controlling parameters will be established. Several GIS-based analysis methods as well as quantitative prediction models for landslide hazard have been proposed in the literature. However, most of these methods have not been applied to rockslides until now. On the basis of this spatial analysis, currently known rock-slope instabilities will be classified and it should be possible to explain their occurrence at their particular place on a regional scale. This knowledge is necessary to finally map the rockslide susceptibility on a regional scale based on a database of past events or on physical processes. Therefore, and for quantifying the rockslide hazard, it is planned to do structural analyses and map old rockslides in the Storfjorden region (Møre & Romsdal) from remote sensing data and fieldwork. Defining and characterising the source areas for all historic events that are registered at the NGUdatabase (www.skrednett.no) as well as previously mapped deposits on the fjord bottom within this region will be the main task for this.
In a second step these results will be validated in another study region as well as on a site-specific study. For the first it will be tested if the previously developed model can explain the existing instabilities in another region. The latter will investigate if the rock-slope instabilities show the same dependencies on a detailed scale as has been shown for a regional scale..
Eksterne veiledere: Lars Blikra, Åknes/Tafjord-prosjektet og Michel Jaboyedoff, Universitetet i Lausanne
Hovedveileder: Professor Bjørn Nilsen | Telefon: xxxxx | Rom: xxxx | Avsluttes: august 2011
40Ar/39Ar geochronology and paleomagnetism of the North Atlantic Igneous Province (NAIP): testify the duration rates and mechanisms of flood basalts eruption in the NAIP, with emphasis on examples from the British Tertiary Province.
Large Igneous Provinces (LIPs) have been linked in cause-effect relationships to continental rifting and break up, genesis of ocean floor, buoyant uplift of the lithosphere, mass extinctions and climate change and hot spots. These links and their consequences have been suggested primarily on the basis of detailed studies of the massive volumes of flood basalts that are characteristic features of all LIPs, and which are documented to have been extruded within very short geologic time periods (on the order of 1-2 m.y. or less). Because LIPs have erupted through continental crust, ocean crust, or both, they are also markers with which to study large-scale plate motion, stretching and rupture of the crust, and thermal and chemical evolution of the mantle through time. However, the general tendency in LIP research to emphasize collection of data to quantify the rates and volumes of production of the short-lived flood basalt eruptions has left a paucity of data for much of a LIP's history that otherwise can last >10 to more than 100 m.y. Several LIPs are located in the Atlantic province. These include the North Atlantic Igneous Province (NAIP), the Central Atlantic Margin Province (CAMP), the Paraná-Etendeka Province (P-E), and the Karoo Igneous Province (KIP). These LIPs, and especially the flood basalt phases of their histories, are often suggested to have played direct roles in the break-up of Pangea and opening of the Atlantic and southern Indian Oceans. However, the timing of eruption of the flood basalts, well constrained for three of the four LIPs through high-precision 40Ar/39Ar geochronology, relative to production of the first sea-floor magnetic anomalies in the vicinity of each province differs significantly from LIP to LIP. Clearly, a direct connection between massive outpouring of flood basalt and continental break up cannot be universally applied on the basis of temporal relationships alone. The lithospheric settings and spatial evolution of these provinces also differ, thus requiring 'LIP-specific' models to establish the relationship between asthenosphere melting, lithospheric stretching and continental break up. The focus in this study will be the NAIP.
Project description and objectives:
The fieldwork of this study will focus on the easily accessible rocks of NW Scotland and the north of Ireland. Previously published work on the geochronology of Mull lavas will be combined with modern paleomagnetic studies of these rocks, complemented by supplementary 40Ar/39Ar geochronology on Mull. In the north of Ireland, the extensive basalt province of Antrim has not been dated with modern isotope geochronology methods, nor has a detailed, modern paleomagnetic study been conducted on the Antrim lava stratigraphy. Thus, a complete magnetostratigraphic study with 40Ar/39Ar geochronology is planned for this area. In Northern Ireland, dikes will also be mapped and dated to attempt to constrain time of their emplacement. Dikes are good markers of stress orientation, but have different significance if emplaced prior to, during or after flood basalt volcanism.
The objectives of the project are to quantify the complete temporal and plate motion history recorded by the North Atlantic LIP through application of two primary tools: 40Ar/39Ar geochronology and paleo-magnetism. Together, the two methods can give constraints on the paleolatitudinal position of a rock at a precise time. This study would address the complete history of the NAIP, of which the flood basalt phase is only one part, in an effort to gain regional understanding about:
- change in rates of plate motion over time as LIP magmatism evolves;
- timing of rapid plate motion relative to flood basalt volcanism;
- temporal relationship of flood basalt volcanism to continental break up (if any);
- causal mechanisms for continental rifting and break up in presence/absence of LIPs.
Hovedveileder: Professor Tore Prestvik | Telefon: xxx | Rom: xxx | Avsluttes: 2009
Stability of natural rock slopes in Norway
The PhD-project will focus on the stability of high, natural rock slopes. The failure mechanisms of such slopes are often poorly understood, and a main goal therefore is to try to reach a better understanding of the engineering geological and rock mechanical factors used in models for analysing rock slope stability and for risk assessment. Among the key issues will be to study time dependent deformation and creep, and to develop a model for probability analysis of large-scale rock slope failures. Field investigation of relevant Norwegian cases (?kerneset, Tafjord, Aurland, Nordnes) will be an important part of the project. The PhD-project will be carried out in close co-operation with the "International Centre for Geohazards" (ICG) and the Geological Survey of Norway (NGU).
Hovedveileder: Professor Bjørn Nilsen | Telefon: 94817 | Rom: F262 | Avsluttes: august 2008
Sedimentological and seismic correlation of heterolithic reservoir rocks: Effects of lithology, differential compaction and diagenetic processes
: Improve well correlation and seismic interpretation in heterolithic reservoir units by examining the effect of sedimentary facies, diagenesis and differential compaction on stratigraphic continuity and seismic signatures at reservoir scale. The project will be executed in collaboration with the NTNU-SOP Project "Sub-seismic reservoir description" that focuses on modelling seismic patterns of layered sequences.
: Heterogeneous sandstone formations offer great challenges for correlation and optimal petroleum production. Flow units and properties are controlled by complex facies variations, but also by diagenesis and compaction. This study deals with the interplay between all these parameters, with emphasis on the role of early/differential compaction on the formation properties. The Lower ?re Formation at Heidrun of alternating sandstones, mudstones and coal-beds is selected as study area as it is heterogeneous and well covered by well logs and various petrophysical data, and as there are still several challenges in sandstone correlation between the wells. A comparative study from another setting (turbidites) may be included optionally, in collaboration with the above-mentioned SOP Project.
: The project is multidisciplinary with the following main tasks and questions:
1) Sandstone correlation (reservoir scale) based on sedimentology and sequence stratigraphy.
2) Interpretation and distribution of diagenesis and compaction.
3) Examine role of diagenesis and differential compaction on reservoir properties and lithology correlation.
4) Examine the possibility of distinguishing and model seismic response of selected characteristic facies intervals.
Task 1 and 2 are based on core study, petrophysical well log data and optical petrography. Task 3 includes literature survey of compaction. Sediment back-stripping will be attempted using improved compaction algorithms. The SBED program will be tested on these rocks for upscaling of sediment properties. Task 4 will use tools (SeisWorks) and procedures developed at IPT (A. Stovas & M. Landr?) as part of the SOP Project for interpretation and modelling of relevant seismic data from Heidrun (2D, 3D?).
Study area and data/materials
: The Heidrun Field, Lower ?re Formation has been suggested as study area in collaboration with Statoil who is asked to provide/give access to the following data and material:
Cores, core data, core photos, petrographic thin-sections, petrophysical logs 1:200 and 1:50 including image logs, seismic data, report list, relevant core reports with supplementary data (XRD etc.). Access to relevant OpenWorks database and SBED (Statoil, Rotvoll).
The PhD project is organised at
Inst. Geol. & Bergteknikk with M.B.E. M?rk as supervisor and in collaboration with participants of the SOP Project (Enclosure) and Statoil: A. N?ss and K. Nordahl.
Erik Hammer (PhD student, Tel. 73594825), firstname.lastname@example.org
Mai Britt E. Mørk (supervisor, Tel. 73594812), email@example.com
Hovedveileder: Professor Mai Britt E. Mørk | Telefon: 94825 | Rom: F264 | Avsluttes:
Hovedveileder: Professor Knut L. Sandvik | Telefon: 94853 | Rom: F284 | Avsluttes: juni 2009
Hovedveileder: Professor Kai Nielsen | Telefon: 41512653 | Rom: F180 | Avsluttes: høsten 2008
Effects of Swelling Clay in Weakness Zones on Rock Support Performance
The objective of the PhD research is to improve the understanding of the interaction between weakness zones containing swelling clay and rock support, and based on this become able to design tunnel support more reliably and cost efficiently. Particular emphasis will be placed on analyzing the performance in such conditions for commonly used rock support such as:
Reinforced shotcrete ribs
Combination of systematic rock bolting and shotcrete
It is the intention to incorporate swelling behaviour into existing, commercially used numerical programs like FLAC-3D, PHASE2, etc. As key input, results from traditional Norwegian swelling tests will be considered, but alternative approaches will also be looked into and discussed. Rational use of such results will be a key issue.
The research will emphasize on effects of swelling load on rock support structures when swelling minerals appear as gouge fillings. Several Norwegian tunnel projects with swelling problems are to be studied during the research.
In addition to empirical models based on results from laboratory swelling tests, the approach of utilizing existing constitutive laws for rheological models in swelling simulation will be examined. Establishing a new constitutive law for swelling will be attempted as well. Parametric study of the rock mass properties and other key factors will also be conducted.
Hovedveileder: Professor Bjørn Nilsen | Telefon: xxxxx | Rom: Fxxx | Avsluttes: august 2012
Critical limitations for Safety, Health and Environment (SHE) in productions of minerals
Besides economical development, the Safety, Health and Environmental aspects are of considerable importance to all industrial activity due to existing rules and regulations, employees, authorities and public interests.
The subjects connected to Safety, Health and Environment varies widely, and the objectives of this project are to investigate different problems connected to critical limitations within the Mineral Industry. Some examples of critical limitations for mineral production may be the official requirements for mineral waste disposals, mineral contamination remediation costs, content of minerals dangerous to health like quartz and asbestos, neighbour relations, general public interest, authorities interest, new rules and regulations and changes in the existing rules and regulations.
Mineral products, size and production lines may be quite different from company to company within the mineral Industry. With regards to this project it?s important to get information on which factors are critical for the individual company within the Mineral Industry in order to influence their future development positively.
Hovedveileder: Professor Tom Myran | Telefon: 94882 | Rom: F274 | Avsluttes: høst 2007
Hovedveileder: Mai Britt Mørk | Telefon: 94859 | Rom: F180 | Avsluttes: høsten 2008