Jamshidi Emad, Kianoush Pooria, Hosseini Navid, Adib Ahmad
National Iranian Oil Company, Exploration Directorate (NIOC-EXP), Tehran, 1994814695, Iran.
Department of Petroleum and Mining Engineering, South Tehran Branch, Islamic Azad University, Tehran, 1777613651, Iran.
Sci Rep. 2024 Aug 17;14(1):19094. doi: 10.1038/s41598-024-69758-w.
Wellbore stability analysis is a critical component of petroleum engineering, evaluating the risks of sanding, reservoir compaction, and casing failures. Laboratory rock mechanical measurements must be scaled up to reservoir scales to achieve accurate results. One challenge lies in upscaling dynamic measurements from petrophysical logs to pseudo-static elastic properties, which has significant implications for oil and gas operations. We present a novel approach that combines laboratory rock mechanical measurements with well-log data to develop a mechanical earth model (MEM) for an Iranian oilfield with over 350 wells. We conducted static elastic property measurements on 40 core samples from various layers and depths of carbonate and sandstone rocks, demonstrating the practical application of our approach. By integrating these measurements with dynamic log data and static-dynamic correlations, we established a framework for evaluating the mechanical properties of different layers. Our findings indicate that the safe mud weight window ranges from 41.5 to 118.59 pcf, while the stable mud weight window ranges from 41.5 to 156 pcf. We demonstrate the importance of conducting parallel rock mechanical studies on cores and logs to reduce uncertainties, costs, and risks during oil and gas operations. We also propose a novel methodology combining lithological characteristics, abnormally high pressure, and borehole instability mechanisms to evaluate the stability of borehole walls. This framework provides a fresh perspective on wellbore stability analysis and offers practical solutions for the industry. Essential novel techniques include developing a geomechanical model that integrates laboratory rock mechanical measurements with well-log data to evaluate mechanical properties and calculate safe and stable mud-weight windows. Our study advances wellbore stability analysis by providing a new method for addressing this long-standing challenge. It offers valuable insights for petroleum engineers working in the oil and gas industry.
井筒稳定性分析是石油工程的关键组成部分，用于评估出砂、储层压实和套管失效的风险。必须将实验室岩石力学测量结果放大到储层规模，才能获得准确的结果。其中一个挑战在于将岩石物理测井的动态测量结果放大到准静态弹性特性，这对油气作业具有重大影响。我们提出了一种新颖的方法，将实验室岩石力学测量与测井数据相结合，为一个拥有350多口井的伊朗油田开发了一个力学地球模型（MEM）。我们对来自碳酸盐岩和砂岩不同层位和深度的40个岩芯样本进行了静态弹性特性测量，展示了我们方法的实际应用。通过将这些测量结果与动态测井数据以及静态-动态相关性相结合，我们建立了一个评估不同层位力学特性的框架。我们的研究结果表明，安全泥浆密度窗口范围为41.5至118.59磅/立方英尺，而稳定泥浆密度窗口范围为41.5至156磅/立方英尺。我们证明了在岩芯和测井上进行并行岩石力学研究对于降低油气作业期间的不确定性、成本和风险的重要性。我们还提出了一种新颖的方法，结合岩性特征、异常高压和井壁失稳机制来评估井壁稳定性。这个框架为井筒稳定性分析提供了新的视角，并为该行业提供了实际解决方案。重要的新颖技术包括开发一个地质力学模型，该模型将实验室岩石力学测量与测井数据相结合，以评估力学特性并计算安全和稳定的泥浆密度窗口。我们的研究通过提供一种解决这一长期挑战的新方法，推进了井筒稳定性分析。它为从事油气行业的石油工程师提供了有价值的见解。
