This paper demonstrates how information obtained while drilling an oil or gas well, is utilized to optimize drilling costs for upcoming wells in the same field by creating a Geological Drilling Log (GDL). The GDL is created by using drilling models specific to the bits used for individual intervals to generate a formation profile of properties for the entire section drilled on a foot by foot basis. The simulation and optimization is used in the field with the GDL to properly select bits (Tricone or Natural Diamond) and operating conditions for the lowest cost per foot.
The concept of a learning curve is utilized by conducting a number of simulations using the GDL, so that the optimum drilling parameters and conditions are eventually obtained. The approach to drilling optimization using a simulator and a GDL in this study showed a substantial reduction in drilling cost. The drilling models used in this study are capable of accurately simulating the drilling of a well and reproducing realistic Rates of Penetration (ROP).