Reservoir Quality in Jurassic and/or Cretaceous sandstone reservoirs located in the northern North Sea area area in wells – the role of sediment composition, provenance, chlorite coating and mechanical and chemical compaction
These projects aim to increase the understanding of the distribution, quality and differences within and between wells within the Early Jurrassic Cook Formation and Early/Middle Cretaceous Agat Formation regionally in the northern North Sea area.
Reservoir properties of sandstones from the Northern North Sea area are a function of mechanical and chemical compaction processes. Important factors include grain size, sorting, mineralogical composition, amount of matrix, amount of early formed cements (carbonate, kaolinite), quartz cementation, chlorite coating, etc). These factors are again a function of provenance, transport processes, climate, depositional environment, etc. A good understanding of the factors controlling the reservoir properties of different sandstone units is essential for prediction of reservoir properties prior to drilling.
The students will work on characterization sandstones from released wells in the area.
The student will work on characterization of relevant reservoir sandstones based on geophysical logs and core material. Sandstones from the Early Jurassic and/or Early/Middle Cretaceous will be included in the thesis projects. Cores from the chosen study areas will be logged to investigate the distribution of sedimentary facies. The facies distribution will be related to petrographic analysis of core material using both optical microscopy and scanning electron microscopy (SEM).
It is of particular interest to study the relation between grain coatings and facies. In addition XRD and Cathode luminescence (CL) will be used to characterize the reservoir sands. CL is an effective method for separating detrital and autigenic quartz phases from each other and CL analysis will therefore be an integral part of the SEM work. Rock Physics may also be incluuded in the thesis projects.
The work will contribute to a better understanding of the reservoir quality found in the potentially chlorite coated reservoirs in the northern North Sea area.