BRITTLENESS INDEX ESTIMATION OF DIGITAL ROCK IMAGES BASED ON NUMERICAL MODELING

• Main Author: Hamid Lubis, Farhan
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/63124
• Institution: Institut Teknologi Bandung

Rock brittleness is a key parameter to quantify and evaluate the brittle nature of rock. A better estimating technique of rock brittleness is crucial for acquiring an efficient stimulation of unconventional shale gas reservoir such as hydraulic fracturing. One way to predict rock brittleness index is by using rock elastic moduli. These physical properties highly depend on complexity of the microstructure, fluid content and mineral composition. The other way is by measuring the rock mineral composition itself. The complexity of the rock’s microstructure can be accurately characterized by using imaging technique such as micro-CT scans. This study used the finite element method to estimate rock brittleness index based on elastic properties on synthetic and digital rock images. We then evaluate the effect of physical and geometrical properties (pore aspect ratio, mineral composition, and water saturation) in determining the rock brittleness characteristic. The results indicate that there is an increase in Young’s modulus along with an increasing in pore aspect ratio to 1, which in turn raises the rock brittleness. Fluid saturation, in this case, water saturation, causes brittleness to be decreased. The rock mineral composition, such as abundant quartz and carbonate content, yields high brittleness values, while high clay content and porosity lower the rock brittleness. Overall, the results imply that pore geometry, fluid saturation, and mineral composition significantly alter the rock strength parameters.