Two Dimensional Finite Element Analysis of Anticline Stress and Prediction of Second Order Fractures
Department
Geosciences and Geological and Petroleum Engineering
Major
Petroleum Engineering
Research Advisor
Eckert, Andreas
Advisor's Department
Geosciences and Geological and Petroleum Engineering
Funding Source
Missouri S&T Opportunities for Undergraduate Research Experiences (OURE) Program
Abstract
This study utilizes two dimensional plane strain finite element analysis to investigate the state of stress and the likelihood of second order fractures associated to a generic anticline structure under varying loading conditions. Depending on the resulting state of stress, the models enable prediction of second order fracture location, likelihood of occurrence, and orientation. The independent variables of the model are the material properties of the rocks, the bedding plane coefficient of friction, and the magnitudes of the horizontal and vertical stress mimicking or simulating extensional, strike-slip, and compressional stress regimes. The analysis shows that decoupling the various bedding planes, i.e. by implementing small inter-bedding plane coefficient of friction has significant influence on the distribution of tensional and compressional stresses in the hinge of the anticline. The crest of the anticline layers experiences tension, while the inner layer in the hinge zone experiences compression. Together with the difference in material properties the resulting state of stress will determine second order fracture distribution. Depending on the location within the structure, either tensile failure, shear failure, or both shear and tensile failures will occur in an anticline setting. Furthermore, the stress regime strongly affects the occurrences of fractures. Failures will most likely occur in a compressional stress regime due to increased strain imposed to the model. The results of this study will help to determine geomechanical risks such as fault seal breach, stable drilling directions, and forecast the failure that will occur in the field.
Biography
Faten is from Kuala Lumpur, Malaysia and currently pursuing her undergraduate studies (BSc) in Petroleum Engineering at Missouri University of Science and Technology. Faten is on a fully funded scholarship by PETRONAS, the Malaysian national oil company. Her interest in petroleum engineering is drilling and exploration. After her graduation in May 2010, she is planning to work as a drilling engineer for PETRONAS in Malaysia. She is currently the Vice President of the Society of Petroleum Engineers, the Secretary of International Students Club, and member of the Malaysian Students Club, the Society of Exploration Geophysics, the Phi Kappa Phi honor society, and the Muslim Students Association. She currently works as a student research assistant for Dr. Andreas Eckert and as a student clerical assistant for the Petroleum Engineering program.
Research Category
Sciences
Presentation Type
Poster Presentation
Document Type
Poster
Location
Upper Atrium/Hallway
Presentation Date
07 Apr 2010, 9:00 am - 11:45 am
Two Dimensional Finite Element Analysis of Anticline Stress and Prediction of Second Order Fractures
Upper Atrium/Hallway
This study utilizes two dimensional plane strain finite element analysis to investigate the state of stress and the likelihood of second order fractures associated to a generic anticline structure under varying loading conditions. Depending on the resulting state of stress, the models enable prediction of second order fracture location, likelihood of occurrence, and orientation. The independent variables of the model are the material properties of the rocks, the bedding plane coefficient of friction, and the magnitudes of the horizontal and vertical stress mimicking or simulating extensional, strike-slip, and compressional stress regimes. The analysis shows that decoupling the various bedding planes, i.e. by implementing small inter-bedding plane coefficient of friction has significant influence on the distribution of tensional and compressional stresses in the hinge of the anticline. The crest of the anticline layers experiences tension, while the inner layer in the hinge zone experiences compression. Together with the difference in material properties the resulting state of stress will determine second order fracture distribution. Depending on the location within the structure, either tensile failure, shear failure, or both shear and tensile failures will occur in an anticline setting. Furthermore, the stress regime strongly affects the occurrences of fractures. Failures will most likely occur in a compressional stress regime due to increased strain imposed to the model. The results of this study will help to determine geomechanical risks such as fault seal breach, stable drilling directions, and forecast the failure that will occur in the field.
