This book focuses on cement bond logs (CBL) as a critical tool for ensuring long-term well integrity. It covers key topics such as acoustic fundamentals, factors influencing cement bond and variable density log (CBL/VDL) readings, cement bond logs evaluation, and methods to address the microannulus effect, which can lead to misleading log results. It also includes a discussion of waveforms, particularly in relation to VDL readings. The book explores how both conventional sonic and new ultrasonic technologies capture and interpret waveforms to assess variations in cement bond integrity. Practical case studies are provided to demonstrate how sonic and ultrasonic CBL interpretation can improve decision-making in assessing well integrity. Additional guidance is provided on evaluating log quality, supervising and witnessing logging operations, and comparing different logging tools.
Cement Bond Logs: Guidelines and Interpretation serves as an essential resource for engineers and researchers seeking to improve wellbore integrity through practical and accurate cement evaluation.
Introduction.- Fundamental Acoustic Parameters.- Cement Bond Logs.-
Cement Bond Logging Tools.- Affecting Wellbore Conditions.- Microannulus vs
Microchannels.- Log Quality Control and Reliability.- Operational Guidelines
for Supervising Acquisition.- Practical CBL Case Studies.- Pressure Integrity
Tests.- Inflow Testing.- Holistic Approach to Cement Evaluation.- Temperature
Noise and Other Methods.- Cement Plugs and P&A Evaluation.- Cement Integrity
in CCUS Well.- HPHT and Geothermal Cement Integrity Evaluation.- Data-Driven
and ML Approaches to Cement Evaluation.
Rahman Ashena, Ph.D., is a senior petroleum engineer with over a decade of field experience in drilling, well completion, and workover operations. He is the founder and senior well engineer at Smart Engineering and Data Analytics, where he leads the application of advanced data analytics to optimize petroleum, geothermal, and CCUS operations. His technical expertise includes well control, geomechanics, cementing, well integrity, and coring, and he has served as a consultant on complex well engineering projects across various regions. Dr. Ashena holds a Masters in Petroleum Well Engineering from Curtin University (2009) and a Ph.D. from Montanuniversität Leoben (2017), where his research focused on geomechanics-driven drilling optimization. He serves as assistant editor-in-chief of the Journal of Petroleum Exploration and Production Technology (Springer). He is the corresponding author of the book Coring Methods and Systems (Springer, 2018), and a contributor to Artificial Intelligence Approaches in Petroleum Geosciences (Springer, 2024).
William K. (Bill) Ott, P.E., is an independent petroleum consultant in Houston, Texas. He founded Well Completion Technology, an international engineering consulting and petroleum industry training firm, in 1986. Before consulting and teaching, Mr. Ott was the division engineer for Halliburtons Far East region based in Singapore. Previously, he was a research field coordinator for Halliburton in Duncan, Oklahoma. Mr. Ott received his B.S. in Chemical Engineering from the University of Missouri. He is a registered professional engineer in Texas, a 50-year SPE member, and an SPE Distinguished Lecturer (2007-08) on the Selection and Design Criteria for Sand Control Screens. He has conducted technical petroleum industry courses worldwide and written numerous technical papers relating to well completion and workover operations. He co-authored the books World Oils Modern Sandface Completion Practices and Mature Oil & Gas Wells Downhole Remediation Handbook.
