Determining and Estimating Drilling Mud Loss Levels Using the Landmark System in the X Oil Field

Abstract

The X Oil Field oil field, is a giant field facing operational challenges during drilling activities, the most prominent being drilling mud loss in various geological formations. This issue adversely affects drilling efficiency and increases operational costs. This study aims to identify the levels of drilling mud loss in the X Oil Field wells and estimate these levels for new wells to support decision-making related to optimal drilling site selection and risk mitigation associated with mud loss. Data on well locations, formation tops, and mud loss values were analyzed using the Landmark system. A database was created within the OpenWorks platform, and the data were processed with the VIR10 (DSG) program for seismic and geological analysis. The study covered data from 56 wells. Four contour maps were prepared to show the distribution of mud loss levels (low, moderate, and high). Additionally, four representative wells were selected for detailed analysis of mud loss levels:  X-53, X-54, X-55, and X-56. The results revealed mud loss in the A, B, C, and D formations, with three levels of occurrence identified across the entire field: low, moderate, and high. Low levels were concentrated in the southern and western parts of the field, moderate levels were distributed in the northern and eastern parts, and high levels were primarily located in the central area. The contour maps showed significant variation in mud loss even among adjacent wells, limiting the ability to generalize spatial data across the whole field. The A formation exhibited the highest drilling mud loss compared to the other formations. Calculation tables developed using Microsoft Excel demonstrated a high capability to estimate mud loss levels for new wells based on data from nearby wells, making them an effective tool for supporting future drilling planning. The study recommends incorporating these results into the geological drilling programs of the X Oil Field, exercising caution when drilling wells at the structural highs of the field where high mud loss occurs. It also advises preparing a lithological distribution map for the A formation correlated with 3D seismic data to better delineate potential mud loss zones. Moreover, acquiring updated 3D seismic data in (Segy-PSTM) format is necessary to improve assessment accuracy. This study serves as a model that can be generalized and applied to other oil fields operated by Basrah Oil Company facing similar mud loss challenges.