Evaluation of Vertical Stress in Southern Iraq: A Comprehensive Analysis Using Well Log Data and Software Modification
Abstract
Vertical stress evaluation is pivotal in the domains of well construction and sand production assessment. This research focuses on estimating vertical stress within the Nahr Umr, Shuaiba, and Zubair layers at depths of 2737.5, 2990.83, and 3083m, respectively, within the Rumaila oil field. Various methodologies, including extrapolation, Miller, Amoco, Wendt non-acoustic, Traugott, and averaging density methods using Techlog 2021, are employed to predict vertical stress.Significantly, the extrapolation method excels in shallow depth calculations, while the Miller method accurately represents actual density values at greater depths, particularly within the Nahr Umr, Shuaiba, and Zubair layers. Remarkably close alignment is observed between the vertical stress values obtained from the Miller and extrapolation methods. For example, at the specified depths, the Miller method yields stress values of 8980, 9373, and 9981 psi, closely resembling the extrapolation method's results of 8987, 9373, and 9987 psi. Alternative techniques, including the Amoco, Wendt non-acoustic, Traugott, and average density methods, yield comparable outcomes. These approaches rely solely on density records as inputs and provide consistent apparent density values from the surface to the intended depth.Incorporating these findings into geomechanical modeling enhances comprehension of rock behavior under varying loads, offering valuable insights for optimized well construction and sand production management strategies. This research underscores the critical importance of understanding vertical stress as a cornerstone in achieving these objectives
