Improving the Reliability of Well Log Data Recorded in Oil and Gas Wells through Quality Control Approaches: A Case Study from a Southern Iraqi Field

Quality control of well logs has always been an important objective in reservoir studies because of the key role played by well logs as input data. This study aims to make a quality control on well logs data for two wells of Yamama formation in southern Iraqi field to ensuring and enhancing the measurement accuracy. In the beginning, the calibration data of before and after surveys are applied as initial evaluation for the quality of density log in well R-1. Then, depth matching is used to fit the depth of all logs in each well. After that, the comparison between the main and repeat sections is helped to check the repeatability. Finally, all uncorrected logs are environmentally corrected to remove the effects of the borehole conditions. The results show that most of the logs measurements are of the best quality and they are perfect for any analysis due to the study findings that the density log has approximately equal calibration readings, and the depth of all logs in each well is matched thus giving the best accuracy, moreover, most logs have good repeatability except for flushed zone resistivity and caliper logs in well R-2 in addition to the environmental correction is improved the measurements of gamma-ray and neutron logs.