Application of geomechanically-based fracture models to a fractured chalk field, offshore Denmark

We have developed a method of created geomechanically-based Discrete Fracture Network models by simulating the nucleation and propagation of natural fractures over geological time, based on linear elastic fracture mechanics and subcritical fracture propagation theory. In this presentation we apply the method to the Kraka field offshore Denmark, which comprises a fractured chalk reservoir developed over a salt pillow.

We calculate the magnitude and orientation of the horizontal strain experienced during development of the salt structure by backstripping, and use this as input to the fracture propagation model. We compare the results with fractures interpreted on borehole images from 5 horizontal wells, as well as lineations observed on ant-tracked seismic data, and find a good match in both orientation and fracture density.