PhD defence: Tala Maria Aabø

Tala Maria Aabø defends her thesis,

Fractures and their influence on Fluid Flow in Chalk

Supervisors:
Associate Professor Kresten Anderskouv, IGN
Professor Lars Nielsen, IGN and GEUS
Professor Lars Stemmerik, GEUS

Assessment committee:
Senior research scientist Peter Frykman, GEUS
Professor Juliette Lamarche, Aix-Marseille Université – France
Professor Klaus Mosegaard (chair), NBI

Summary:
This thesis is focused on fractures and their influence on fluid flow in chalk. An outcrop analogues to the North Sea chalk reservoirs is subjected to structural and fracture characterization, using extensive workflows involving ground penetrating radar (GPR), shallow seismic and a time series of digital outcrop models (DOMs). The workflows have resulted in a 3D model of the structural elements at the site and the mapping of 27 400 fractures. Statistical and geological analyses show that the outcrop is characterized by layer-bound fractures, in which flow is likely smooth. The observed fracture attributes (orientation, density, length and spacing) are reproduced at the site using a geomechanically based modelling tool for dynamic simulation of fracture formation. This provides insights into the strain regime, which is likely to have formed the fracture network in the outcrop analogue. Sensitivity analyses on the dynamic fracture modelling tool enables subsurface usage.

A digital version of the PhD thesis can be obtained from the PhD secretary phd@ign.ku.dk