Petrophyssics of Paleogene sediments

Physical properties of sediments are controlled by mineralogical composition, texture and burial depth. The main objective of this PhD project is to investigate, evaluate and characterize the influence of mineralogical composition and burial depth (burial temperature, overburden and effective stresses, pore-fluid pressure and time) on petrophysical properties of Palaeogene sediments (Eocene chalk, siliceous ooze sediments and shale).

This is not straight forward especially for shale and siliceous ooze because of the complicated nature of their mineralogical composition and texture. To limit the scope, we focused on three different geological settings (Danish, Norwegian Sea and Atlantic Ocean basins). If the factors governing the physical properties are understood, it will help three issues: 1) chalk porosity prediction from sonic velocity data; 2) evaluation of hydrocarbon reservoir potential of siliceous ooze; 3) rock physical modeling of shale for seismic interpretation.

This PhD research project is divided into three main subprojects. The first topic focused on the physical properties of Eocene chalk based on the Ocean Drilling Program data from the Atlantic Ocean. A paper (under review) on porosity depth trends of Eocene chalk was prepared. The second topic was about characterization, evaluation and interpretation of siliceous ooze. Here, we integrated well logs and core analysis data with mineralogical and other data of siliceous ooze. A consistent interpretation was made and a paper on petrophysical analysis of siliceous ooze was produced (ready for review).

The third topic involved laboratory work on XRD analysis, surface area (BET), elastic wave velocity and electrical resistivity measurements on Palaeogene clay (shale). The obtained results will be evaluated and integrated with the available geotechnical data to relate the elastic moduli of shale to BET and mineralogy of shale. A paper (in process) about rock physical modeling of shale for seismic interpretation will be prepared.

Supervisor: Prof. Ida Lykke Fabricius, ilfa@byg.dtu.dk