Perpustakaan Digital ITB

Hydraulic fracturing success is strongly influenced by the accuracy of rock mechanical property characterization, particularly in data-limited environments where direct measurements are scarce. This study investigates the sensitivity of hydraulic fracturing design performance to variations in key rock mechanical parameters—Young’s modulus, Poisson’s ratio, and fracture toughness—in the Clastic Reservoir. Due to the absence of sonic log data, these properties were estimated based on literature and analog formations, then tested across a wide sensitivity range using fracture simulations using 3D Shear-Decoupled model. Two reservoir zones, Clastic Upper and Lower, were analyzed to assess the design's robustness. Results indicate that the hydraulic fracturing design for the Lower formation is highly resilient, with minimal variation in fracture geometry and five-year production output, owing to strong stress contrast provided by shale caprock and underburden. In contrast, the Upper formation exhibited significant fracture height growth and conductivity loss when Young’s modulus and fracture toughness was reduced by 20%, and Poisson’s ratio was increased by 20% or more. Young’s modulus plays a more dominant role as rock mechanism properties. This response was driven by a weaker stress contrast between the reservoir and the overlying conglomeratic sandstone, resulting in vertical fracture containment failure and reduced production performance. The study concludes that proper characterization of rock mechanical properties—especially the stress contrast between reservoir and bounding formations—is crucial for optimizing fracture containment and ensuring treatment success under subsurface uncertainty.