Data-Driven Reservoir Fluid Evaluation While Drilling: An Integrated Technology for Advanced Mud Gas Analysis

Summary The GOLD (Gas Oil Logging while Drilling) system is an integrated technology designed for real-time reservoir fluid evaluation while drilling. It combines thermodynamic gas extraction, advanced mud gas chromatography, and cloud-based predictive modeling to infer key fluid properties such as API gravity and gas-oil ratio (GOR) directly from mud gas data. GOLD employs a constant-volume suction probe, thermal control, and a chromatograph for gas analysis. Surface data is processed in the cloud using multivariate statistical models and machine learning trained on extensive PVT datasets. This allows fluid zone detection, fluid typing, biodegradation analysis, and molar composition estimation without the need for formation tests or laboratory PVT analysis. Field deployments, including in Brazilian pre-salt wells, demonstrated high accuracy, with deviations of less than ±5°API and ±200 m3∕m3 GOR when compared to laboratory results. GOLD offers a fast, scalable, and cost-effective alternative for digital reservoir characterization.