Stress distribution around kerogen particles as a measure of the initiation of bitumen-filled microfractures in organic-rich source rocks

Akbar N Wicaksono; Israa S Abu-Mahfouz; Erdem Idiz; Joe Cartwright; J Carlos Santamarina; Volker C Vahrenkamp

doi:10.1016/j.mex.2022.101817

Stress distribution around kerogen particles as a measure of the initiation of bitumen-filled microfractures in organic-rich source rocks

MethodsX. 2022 Aug 20:9:101817. doi: 10.1016/j.mex.2022.101817. eCollection 2022.

Authors

Akbar N Wicaksono¹, Israa S Abu-Mahfouz^{1

2}, Erdem Idiz³, Joe Cartwright³, J Carlos Santamarina¹, Volker C Vahrenkamp¹

Affiliations

¹ Ali I. Al-Naimi Petroleum Engineering Research Centre, King Abdullah University of Science & Technology (KAUST), Thuwal, 23955 Saudi Arabia.
² Department of Geosciences, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia.
³ Department of Earth Sciences, University of Oxford, Oxford OX1 3AN, UK.

Abstract

In this article, we present a method used to model the initiation of bitumen-filled microfractures in immature, organic-rich source rocks. The first part presents the method used to calculate the stress distribution around the kerogen particles. The second part explains the method used to calculate the pressure change as a function of the transformation ratio and the resulting overpressure.•The effective principal stresses acting on the kerogen boundary were calculated.•Kerogen geometries were determined using the measured aspect ratio of the kerogen traces obtained from the petrography observation.•To estimate overpressure, the increase in pressure due to the transformation of kerogen to bitumen was calculated.

Keywords: Bitumen-filled microfractures; Kerogen shape; Overpressure; Source rocks; Stress distribution.