Geosteering is a critical technique used in oil and gas well drilling, especially for horizontal wells, to position the wellbore within the hydrocarbon-bearing formation accurately. To carry out this process, the gamma-ray logs from the laterals are matched with logs from a reference vertical well to position the lateral in the desired path accurately. A significant amount of research has been conducted in geosteering, including the utilization of machine learning and the development of automated geosteering techniques. Due to the high cost of repeated use of steering, it can be helpful to establish a logical mathematical correlation between two or more parameters for movement within the reservoir. This study investigates the relationship between Rate of Penetration (ROP) and gas ratio data in three laterals drilled in a heterogeneous limestone reservoir in Iran by plotting normalized ROP vs. normalized gas ratio. Geomaster software is used to direct the geosteering process in order to ascertain the reservoir's depth. After normalizing the ROP and gas ratio data and eliminating outliers, various models, including linear, polynomial, power, and exponential, are applied using MATLAB. As a result, we can observe that for the majority of laterals, the second-degree polynomial model offers the best correlation. Also, the presence of heterogeneity affects some results of laterals. These results can be applied to reduce the expenses associated with recurrent geosteering operations, enable the drilling of new or extended laterals, and optimize drilling operations in the field.
Fathi Hafshejani, S. , Ahi, M. , & Jamshidi, S. (2025). Improving geosteering performance using rate of penetration and gas ratio: case studies in a limestone reservoir. Journal of Petroleum Science and Technology, (), -. doi: 10.22078/jpst.2025.5534.1951
MLA
Sina Fathi Hafshejani; Mohamadmehdy Ahi; Saeid Jamshidi. "Improving geosteering performance using rate of penetration and gas ratio: case studies in a limestone reservoir", Journal of Petroleum Science and Technology, , , 2025, -. doi: 10.22078/jpst.2025.5534.1951
HARVARD
Fathi Hafshejani, S., Ahi, M., Jamshidi, S. (2025). 'Improving geosteering performance using rate of penetration and gas ratio: case studies in a limestone reservoir', Journal of Petroleum Science and Technology, (), pp. -. doi: 10.22078/jpst.2025.5534.1951
CHICAGO
S. Fathi Hafshejani , M. Ahi and S. Jamshidi, "Improving geosteering performance using rate of penetration and gas ratio: case studies in a limestone reservoir," Journal of Petroleum Science and Technology, (2025): -, doi: 10.22078/jpst.2025.5534.1951
VANCOUVER
Fathi Hafshejani, S., Ahi, M., Jamshidi, S. Improving geosteering performance using rate of penetration and gas ratio: case studies in a limestone reservoir. Journal of Petroleum Science and Technology, 2025; (): -. doi: 10.22078/jpst.2025.5534.1951
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