Sedimentological controls on chlorite-coats on reservoir sandstones: Cook Formation

Project description
Sandstone reservoirs buried to depths more than 2.5 km lose porosity and permeability as they are buried further due to precipitation of quarts cement on grain surfaces. However, in some sandstones there are grain coatings of chlorite, and these coats inhibit quartz cementation and thus preserve reservoir properties up to depths of 6 km. Chlorite in reservoirs also rapdily mineralize CO2, which may become important for permanent CO2 sequestration. However, the distribution of chlorite coats in the subsurface is largely unknown, and understanding of how to predict presence of porosity-preserving chlorite coats is lacking.

In this project, the candidate will investigate grain coat properties, provenance and sedimentology of the Cook Formation in the SE parts of the Norwegian North Sea. The candidate will have access to existing petrographic data, acquire new petrographic data, and perform sedimentary logging. The goals are to investigate the sedimentology and petrography of the Cook Formation in the SE parts of the N North Sea, investigate if the quality of grain-coats are different here compared to the more well studied NW N North Sea, and investigate fundamental controls on chlorite coats in sandstone reservoirs.

Proposed course plan during the master's degree (60 ECTS):
GEOV261
GEOV360
GEOV352
GEOV300
GEOV302
GEOV241
GEOV361

External data
Core, well, seismic, and petrographic data from project partners Equinor and AkerBP

Field- lab and analysis
Core logging at the Equinor, AkerBP and Norwegian Petroleum Directorate core stores
Sedimentological analysis of core data
Petrographic work on thin sections
Work on the Scanning-Electron Microscope lab